1b2441318SGreg Kroah-Hartman# SPDX-License-Identifier: GPL-2.0 2daa93fabSSam Ravnborg# Select 32 or 64 bit 3daa93fabSSam Ravnborgconfig 64BIT 4104daea1SMasahiro Yamada bool "64-bit kernel" if "$(ARCH)" = "x86" 5104daea1SMasahiro Yamada default "$(ARCH)" != "i386" 68f9ca475SIngo Molnar ---help--- 7daa93fabSSam Ravnborg Say yes to build a 64-bit kernel - formerly known as x86_64 8daa93fabSSam Ravnborg Say no to build a 32-bit kernel - formerly known as i386 9daa93fabSSam Ravnborg 10daa93fabSSam Ravnborgconfig X86_32 113120e25eSJan Beulich def_bool y 123120e25eSJan Beulich depends on !64BIT 13341c787eSIngo Molnar # Options that are inherently 32-bit kernel only: 14341c787eSIngo Molnar select ARCH_WANT_IPC_PARSE_VERSION 15341c787eSIngo Molnar select CLKSRC_I8253 16341c787eSIngo Molnar select CLONE_BACKWARDS 17117ed454SThomas Gleixner select HAVE_DEBUG_STACKOVERFLOW 18341c787eSIngo Molnar select MODULES_USE_ELF_REL 19341c787eSIngo Molnar select OLD_SIGACTION 20daa93fabSSam Ravnborg 21daa93fabSSam Ravnborgconfig X86_64 223120e25eSJan Beulich def_bool y 233120e25eSJan Beulich depends on 64BIT 24d94e0685SIngo Molnar # Options that are inherently 64-bit kernel only: 25*4eb0716eSAlexandre Ghiti select ARCH_HAS_GIGANTIC_PAGE 26d94e0685SIngo Molnar select ARCH_SUPPORTS_INT128 27d94e0685SIngo Molnar select ARCH_USE_CMPXCHG_LOCKREF 28d94e0685SIngo Molnar select HAVE_ARCH_SOFT_DIRTY 29d94e0685SIngo Molnar select MODULES_USE_ELF_RELA 30f616ab59SChristoph Hellwig select NEED_DMA_MAP_STATE 3109230cbcSChristoph Hellwig select SWIOTLB 32f8781c4aSDominik Brodowski select ARCH_HAS_SYSCALL_WRAPPER 331032c0baSSam Ravnborg 34d94e0685SIngo Molnar# 35d94e0685SIngo Molnar# Arch settings 36d94e0685SIngo Molnar# 37d94e0685SIngo Molnar# ( Note that options that are marked 'if X86_64' could in principle be 38d94e0685SIngo Molnar# ported to 32-bit as well. ) 39d94e0685SIngo Molnar# 408d5fffb9SSam Ravnborgconfig X86 413c2362e6SHarvey Harrison def_bool y 42c763ea26SIngo Molnar # 43c763ea26SIngo Molnar # Note: keep this list sorted alphabetically 44c763ea26SIngo Molnar # 456471b825SIngo Molnar select ACPI_LEGACY_TABLES_LOOKUP if ACPI 466e0a0ea1SGraeme Gregory select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI 47942fa985SYury Norov select ARCH_32BIT_OFF_T if X86_32 486471b825SIngo Molnar select ARCH_CLOCKSOURCE_DATA 492a21ad57SThomas Gleixner select ARCH_CLOCKSOURCE_INIT 506471b825SIngo Molnar select ARCH_DISCARD_MEMBLOCK 5191dda51aSAleksey Makarov select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI 52fa5b6ec9SLaura Abbott select ARCH_HAS_DEBUG_VIRTUAL 5321266be9SDan Williams select ARCH_HAS_DEVMEM_IS_ALLOWED 546471b825SIngo Molnar select ARCH_HAS_ELF_RANDOMIZE 5572d93104SLinus Torvalds select ARCH_HAS_FAST_MULTIPLIER 56316d097cSDave Hansen select ARCH_HAS_FILTER_PGPROT 576974f0c4SDaniel Micay select ARCH_HAS_FORTIFY_SOURCE 58957e3facSRiku Voipio select ARCH_HAS_GCOV_PROFILE_ALL 595c9a8750SDmitry Vyukov select ARCH_HAS_KCOV if X86_64 6010bcc80eSMathieu Desnoyers select ARCH_HAS_MEMBARRIER_SYNC_CORE 61c763ea26SIngo Molnar select ARCH_HAS_PMEM_API if X86_64 623010a5eaSLaurent Dufour select ARCH_HAS_PTE_SPECIAL 6339208aa7SKees Cook select ARCH_HAS_REFCOUNT 640aed55afSDan Williams select ARCH_HAS_UACCESS_FLUSHCACHE if X86_64 65092b31aaSDan Williams select ARCH_HAS_UACCESS_MCSAFE if X86_64 && X86_MCE 66d2852a22SDaniel Borkmann select ARCH_HAS_SET_MEMORY 67d253ca0cSRick Edgecombe select ARCH_HAS_SET_DIRECT_MAP 68ad21fc4fSLaura Abbott select ARCH_HAS_STRICT_KERNEL_RWX 69ad21fc4fSLaura Abbott select ARCH_HAS_STRICT_MODULE_RWX 70ac1ab12aSMathieu Desnoyers select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE 71c6d30853SAndrey Ryabinin select ARCH_HAS_UBSAN_SANITIZE_ALL 7265f7d049SOliver O'Halloran select ARCH_HAS_ZONE_DEVICE if X86_64 736471b825SIngo Molnar select ARCH_HAVE_NMI_SAFE_CMPXCHG 746471b825SIngo Molnar select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI 7577fbbc81SMark Salter select ARCH_MIGHT_HAVE_PC_PARPORT 765e2c18c0SMark Salter select ARCH_MIGHT_HAVE_PC_SERIO 773599fe12SThomas Gleixner select ARCH_STACKWALK 782c870e61SArnd Bergmann select ARCH_SUPPORTS_ACPI 796471b825SIngo Molnar select ARCH_SUPPORTS_ATOMIC_RMW 806471b825SIngo Molnar select ARCH_SUPPORTS_NUMA_BALANCING if X86_64 816471b825SIngo Molnar select ARCH_USE_BUILTIN_BSWAP 826471b825SIngo Molnar select ARCH_USE_QUEUED_RWLOCKS 836471b825SIngo Molnar select ARCH_USE_QUEUED_SPINLOCKS 84ce4a4e56SAndy Lutomirski select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH 85c763ea26SIngo Molnar select ARCH_WANTS_DYNAMIC_TASK_STRUCT 8638d8b4e6SHuang Ying select ARCH_WANTS_THP_SWAP if X86_64 876471b825SIngo Molnar select BUILDTIME_EXTABLE_SORT 886471b825SIngo Molnar select CLKEVT_I8253 896471b825SIngo Molnar select CLOCKSOURCE_VALIDATE_LAST_CYCLE 906471b825SIngo Molnar select CLOCKSOURCE_WATCHDOG 916471b825SIngo Molnar select DCACHE_WORD_ACCESS 9245471cd9SLinus Torvalds select EDAC_ATOMIC_SCRUB 9345471cd9SLinus Torvalds select EDAC_SUPPORT 946471b825SIngo Molnar select GENERIC_CLOCKEVENTS 956471b825SIngo Molnar select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC) 966471b825SIngo Molnar select GENERIC_CLOCKEVENTS_MIN_ADJUST 976471b825SIngo Molnar select GENERIC_CMOS_UPDATE 986471b825SIngo Molnar select GENERIC_CPU_AUTOPROBE 9961dc0f55SThomas Gleixner select GENERIC_CPU_VULNERABILITIES 1006471b825SIngo Molnar select GENERIC_EARLY_IOREMAP 1016471b825SIngo Molnar select GENERIC_FIND_FIRST_BIT 1026471b825SIngo Molnar select GENERIC_IOMAP 103c7d6c9ddSThomas Gleixner select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP 1040fa115daSThomas Gleixner select GENERIC_IRQ_MATRIX_ALLOCATOR if X86_LOCAL_APIC 105ad7a929fSThomas Gleixner select GENERIC_IRQ_MIGRATION if SMP 1066471b825SIngo Molnar select GENERIC_IRQ_PROBE 107c201c917SThomas Gleixner select GENERIC_IRQ_RESERVATION_MODE 1086471b825SIngo Molnar select GENERIC_IRQ_SHOW 1096471b825SIngo Molnar select GENERIC_PENDING_IRQ if SMP 1106471b825SIngo Molnar select GENERIC_SMP_IDLE_THREAD 1116471b825SIngo Molnar select GENERIC_STRNCPY_FROM_USER 1126471b825SIngo Molnar select GENERIC_STRNLEN_USER 1136471b825SIngo Molnar select GENERIC_TIME_VSYSCALL 1147edaeb68SThomas Gleixner select HARDLOCKUP_CHECK_TIMESTAMP if X86_64 1156471b825SIngo Molnar select HAVE_ACPI_APEI if ACPI 1166471b825SIngo Molnar select HAVE_ACPI_APEI_NMI if ACPI 1176471b825SIngo Molnar select HAVE_ALIGNED_STRUCT_PAGE if SLUB 1186471b825SIngo Molnar select HAVE_ARCH_AUDITSYSCALL 1196471b825SIngo Molnar select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE 1206471b825SIngo Molnar select HAVE_ARCH_JUMP_LABEL 121b34006c4SArd Biesheuvel select HAVE_ARCH_JUMP_LABEL_RELATIVE 122d17a1d97SAndrey Ryabinin select HAVE_ARCH_KASAN if X86_64 1236471b825SIngo Molnar select HAVE_ARCH_KGDB 1249e08f57dSDaniel Cashman select HAVE_ARCH_MMAP_RND_BITS if MMU 1259e08f57dSDaniel Cashman select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT 1261b028f78SDmitry Safonov select HAVE_ARCH_COMPAT_MMAP_BASES if MMU && COMPAT 127271ca788SArd Biesheuvel select HAVE_ARCH_PREL32_RELOCATIONS 1286471b825SIngo Molnar select HAVE_ARCH_SECCOMP_FILTER 129f7d83c1cSKees Cook select HAVE_ARCH_THREAD_STRUCT_WHITELIST 130afaef01cSAlexander Popov select HAVE_ARCH_STACKLEAK 1316471b825SIngo Molnar select HAVE_ARCH_TRACEHOOK 1326471b825SIngo Molnar select HAVE_ARCH_TRANSPARENT_HUGEPAGE 133a00cc7d9SMatthew Wilcox select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64 134e37e43a4SAndy Lutomirski select HAVE_ARCH_VMAP_STACK if X86_64 135c763ea26SIngo Molnar select HAVE_ARCH_WITHIN_STACK_FRAMES 1366471b825SIngo Molnar select HAVE_CMPXCHG_DOUBLE 1376471b825SIngo Molnar select HAVE_CMPXCHG_LOCAL 1386471b825SIngo Molnar select HAVE_CONTEXT_TRACKING if X86_64 139c1bd55f9SJosh Triplett select HAVE_COPY_THREAD_TLS 1406471b825SIngo Molnar select HAVE_C_RECORDMCOUNT 1416471b825SIngo Molnar select HAVE_DEBUG_KMEMLEAK 1429c5a3621SAkinobu Mita select HAVE_DMA_CONTIGUOUS 143677aa9f7SSteven Rostedt select HAVE_DYNAMIC_FTRACE 14406aeaaeaSMasami Hiramatsu select HAVE_DYNAMIC_FTRACE_WITH_REGS 14503f5781bSWang YanQing select HAVE_EBPF_JIT 14658340a07SJohannes Berg select HAVE_EFFICIENT_UNALIGNED_ACCESS 1476630a8e5SChristoph Hellwig select HAVE_EISA 1485f56a5dfSJiri Slaby select HAVE_EXIT_THREAD 149644e0e8dSSteven Rostedt (VMware) select HAVE_FENTRY if X86_64 || DYNAMIC_FTRACE 1506471b825SIngo Molnar select HAVE_FTRACE_MCOUNT_RECORD 1516471b825SIngo Molnar select HAVE_FUNCTION_GRAPH_TRACER 1526471b825SIngo Molnar select HAVE_FUNCTION_TRACER 1536b90bd4bSEmese Revfy select HAVE_GCC_PLUGINS 1540067f129SK.Prasad select HAVE_HW_BREAKPOINT 1556471b825SIngo Molnar select HAVE_IDE 1566471b825SIngo Molnar select HAVE_IOREMAP_PROT 1576471b825SIngo Molnar select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64 1586471b825SIngo Molnar select HAVE_IRQ_TIME_ACCOUNTING 1596471b825SIngo Molnar select HAVE_KERNEL_BZIP2 1606471b825SIngo Molnar select HAVE_KERNEL_GZIP 1616471b825SIngo Molnar select HAVE_KERNEL_LZ4 1626471b825SIngo Molnar select HAVE_KERNEL_LZMA 1636471b825SIngo Molnar select HAVE_KERNEL_LZO 1646471b825SIngo Molnar select HAVE_KERNEL_XZ 1656471b825SIngo Molnar select HAVE_KPROBES 1666471b825SIngo Molnar select HAVE_KPROBES_ON_FTRACE 167540adea3SMasami Hiramatsu select HAVE_FUNCTION_ERROR_INJECTION 1686471b825SIngo Molnar select HAVE_KRETPROBES 1696471b825SIngo Molnar select HAVE_KVM 1706471b825SIngo Molnar select HAVE_LIVEPATCH if X86_64 1716471b825SIngo Molnar select HAVE_MEMBLOCK_NODE_MAP 1720102752eSFrederic Weisbecker select HAVE_MIXED_BREAKPOINTS_REGS 173ee9f8fceSJosh Poimboeuf select HAVE_MOD_ARCH_SPECIFIC 1749f132f7eSJoel Fernandes (Google) select HAVE_MOVE_PMD 17542a0bb3fSPetr Mladek select HAVE_NMI 1766471b825SIngo Molnar select HAVE_OPROFILE 1776471b825SIngo Molnar select HAVE_OPTPROBES 1786471b825SIngo Molnar select HAVE_PCSPKR_PLATFORM 1796471b825SIngo Molnar select HAVE_PERF_EVENTS 180c01d4323SFrederic Weisbecker select HAVE_PERF_EVENTS_NMI 18192e5aae4SNicholas Piggin select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && HAVE_PERF_EVENTS_NMI 182eb01d42aSChristoph Hellwig select HAVE_PCI 183c5e63197SJiri Olsa select HAVE_PERF_REGS 184c5ebcedbSJiri Olsa select HAVE_PERF_USER_STACK_DUMP 18548a8b97cSPeter Zijlstra select HAVE_RCU_TABLE_FREE if PARAVIRT 1866471b825SIngo Molnar select HAVE_REGS_AND_STACK_ACCESS_API 1876415b38bSJiri Slaby select HAVE_RELIABLE_STACKTRACE if X86_64 && (UNWINDER_FRAME_POINTER || UNWINDER_ORC) && STACK_VALIDATION 1883c88ee19SMasami Hiramatsu select HAVE_FUNCTION_ARG_ACCESS_API 189d148eac0SMasahiro Yamada select HAVE_STACKPROTECTOR if CC_HAS_SANE_STACKPROTECTOR 190c763ea26SIngo Molnar select HAVE_STACK_VALIDATION if X86_64 191d6761b8fSMathieu Desnoyers select HAVE_RSEQ 1926471b825SIngo Molnar select HAVE_SYSCALL_TRACEPOINTS 1936471b825SIngo Molnar select HAVE_UNSTABLE_SCHED_CLOCK 1947c68af6eSAvi Kivity select HAVE_USER_RETURN_NOTIFIER 19505736e4aSThomas Gleixner select HOTPLUG_SMT if SMP 196c0185808SThomas Gleixner select IRQ_FORCED_THREADING 19786596f0aSChristoph Hellwig select NEED_SG_DMA_LENGTH 1982eac9c2dSChristoph Hellwig select PCI_DOMAINS if PCI 199625210cfSSinan Kaya select PCI_LOCKLESS_CONFIG if PCI 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 GENERIC_CALIBRATE_DELAY 2711032c0baSSam Ravnborg def_bool y 2721032c0baSSam Ravnborg 2739a0b8415Svenkatesh.pallipadi@intel.comconfig ARCH_HAS_CPU_RELAX 2749a0b8415Svenkatesh.pallipadi@intel.com def_bool y 2758d5fffb9SSam Ravnborg 2761b27d05bSPekka Enbergconfig ARCH_HAS_CACHE_LINE_SIZE 2771b27d05bSPekka Enberg def_bool y 2781b27d05bSPekka Enberg 279316d097cSDave Hansenconfig ARCH_HAS_FILTER_PGPROT 280316d097cSDave Hansen def_bool y 281316d097cSDave Hansen 282dd5af90aSMike Travisconfig HAVE_SETUP_PER_CPU_AREA 28389c9c4c5SBrian Gerst def_bool y 284b32ef636Stravis@sgi.com 28508fc4580STejun Heoconfig NEED_PER_CPU_EMBED_FIRST_CHUNK 28608fc4580STejun Heo def_bool y 28708fc4580STejun Heo 28808fc4580STejun Heoconfig NEED_PER_CPU_PAGE_FIRST_CHUNK 28911124411STejun Heo def_bool y 29011124411STejun Heo 291801e4062SJohannes Bergconfig ARCH_HIBERNATION_POSSIBLE 292801e4062SJohannes Berg def_bool y 293801e4062SJohannes Berg 294f4cb5700SJohannes Bergconfig ARCH_SUSPEND_POSSIBLE 295f4cb5700SJohannes Berg def_bool y 296f4cb5700SJohannes Berg 297cfe28c5dSSteve Capperconfig ARCH_WANT_HUGE_PMD_SHARE 298cfe28c5dSSteve Capper def_bool y 299cfe28c5dSSteve Capper 30053313b2cSSteve Capperconfig ARCH_WANT_GENERAL_HUGETLB 30153313b2cSSteve Capper def_bool y 30253313b2cSSteve Capper 3038d5fffb9SSam Ravnborgconfig ZONE_DMA32 304e0fd24a3SJan Beulich def_bool y if X86_64 3058d5fffb9SSam Ravnborg 3068d5fffb9SSam Ravnborgconfig AUDIT_ARCH 307e0fd24a3SJan Beulich def_bool y if X86_64 3088d5fffb9SSam Ravnborg 309765c68bdSIngo Molnarconfig ARCH_SUPPORTS_OPTIMIZED_INLINING 310765c68bdSIngo Molnar def_bool y 311765c68bdSIngo Molnar 3126a11f75bSAkinobu Mitaconfig ARCH_SUPPORTS_DEBUG_PAGEALLOC 3136a11f75bSAkinobu Mita def_bool y 3146a11f75bSAkinobu Mita 315d6f2d75aSAndrey Ryabininconfig KASAN_SHADOW_OFFSET 316d6f2d75aSAndrey Ryabinin hex 317d6f2d75aSAndrey Ryabinin depends on KASAN 318d6f2d75aSAndrey Ryabinin default 0xdffffc0000000000 319d6f2d75aSAndrey Ryabinin 32069575d38SShane Wangconfig HAVE_INTEL_TXT 32169575d38SShane Wang def_bool y 3226ea30386SKees Cook depends on INTEL_IOMMU && ACPI 32369575d38SShane Wang 3246b0c3d44SSam Ravnborgconfig X86_32_SMP 3256b0c3d44SSam Ravnborg def_bool y 3266b0c3d44SSam Ravnborg depends on X86_32 && SMP 3276b0c3d44SSam Ravnborg 3286b0c3d44SSam Ravnborgconfig X86_64_SMP 3296b0c3d44SSam Ravnborg def_bool y 3306b0c3d44SSam Ravnborg depends on X86_64 && SMP 3316b0c3d44SSam Ravnborg 332ccbeed3aSTejun Heoconfig X86_32_LAZY_GS 333ccbeed3aSTejun Heo def_bool y 3348458f8c2SMasahiro Yamada depends on X86_32 && !STACKPROTECTOR 335ccbeed3aSTejun Heo 3362b144498SSrikar Dronamrajuconfig ARCH_SUPPORTS_UPROBES 3372b144498SSrikar Dronamraju def_bool y 3382b144498SSrikar Dronamraju 339d20642f0SRob Herringconfig FIX_EARLYCON_MEM 340d20642f0SRob Herring def_bool y 341d20642f0SRob Herring 34294d49eb3SKirill A. Shutemovconfig DYNAMIC_PHYSICAL_MASK 34394d49eb3SKirill A. Shutemov bool 34494d49eb3SKirill A. Shutemov 34598233368SKirill A. Shutemovconfig PGTABLE_LEVELS 34698233368SKirill A. Shutemov int 34777ef56e4SKirill A. Shutemov default 5 if X86_5LEVEL 34898233368SKirill A. Shutemov default 4 if X86_64 34998233368SKirill A. Shutemov default 3 if X86_PAE 35098233368SKirill A. Shutemov default 2 35198233368SKirill A. Shutemov 3522a61f474SMasahiro Yamadaconfig CC_HAS_SANE_STACKPROTECTOR 3532a61f474SMasahiro Yamada bool 3542a61f474SMasahiro Yamada default $(success,$(srctree)/scripts/gcc-x86_64-has-stack-protector.sh $(CC)) if 64BIT 3552a61f474SMasahiro Yamada default $(success,$(srctree)/scripts/gcc-x86_32-has-stack-protector.sh $(CC)) 3562a61f474SMasahiro Yamada help 3572a61f474SMasahiro Yamada We have to make sure stack protector is unconditionally disabled if 3582a61f474SMasahiro Yamada the compiler produces broken code. 3592a61f474SMasahiro Yamada 360506f1d07SSam Ravnborgmenu "Processor type and features" 361506f1d07SSam Ravnborg 3625ee71535SRandy Dunlapconfig ZONE_DMA 3635ee71535SRandy Dunlap bool "DMA memory allocation support" if EXPERT 3645ee71535SRandy Dunlap default y 3655ee71535SRandy Dunlap help 3665ee71535SRandy Dunlap DMA memory allocation support allows devices with less than 32-bit 3675ee71535SRandy Dunlap addressing to allocate within the first 16MB of address space. 3685ee71535SRandy Dunlap Disable if no such devices will be used. 3695ee71535SRandy Dunlap 3705ee71535SRandy Dunlap If unsure, say Y. 3715ee71535SRandy Dunlap 372506f1d07SSam Ravnborgconfig SMP 373506f1d07SSam Ravnborg bool "Symmetric multi-processing support" 374506f1d07SSam Ravnborg ---help--- 375506f1d07SSam Ravnborg This enables support for systems with more than one CPU. If you have 3764a474157SRobert Graffham a system with only one CPU, say N. If you have a system with more 3774a474157SRobert Graffham than one CPU, say Y. 378506f1d07SSam Ravnborg 3794a474157SRobert Graffham If you say N here, the kernel will run on uni- and multiprocessor 380506f1d07SSam Ravnborg machines, but will use only one CPU of a multiprocessor machine. If 381506f1d07SSam Ravnborg you say Y here, the kernel will run on many, but not all, 3824a474157SRobert Graffham uniprocessor machines. On a uniprocessor machine, the kernel 383506f1d07SSam Ravnborg will run faster if you say N here. 384506f1d07SSam Ravnborg 385506f1d07SSam Ravnborg Note that if you say Y here and choose architecture "586" or 386506f1d07SSam Ravnborg "Pentium" under "Processor family", the kernel will not work on 486 387506f1d07SSam Ravnborg architectures. Similarly, multiprocessor kernels for the "PPro" 388506f1d07SSam Ravnborg architecture may not work on all Pentium based boards. 389506f1d07SSam Ravnborg 390506f1d07SSam Ravnborg People using multiprocessor machines who say Y here should also say 391506f1d07SSam Ravnborg Y to "Enhanced Real Time Clock Support", below. The "Advanced Power 392506f1d07SSam Ravnborg Management" code will be disabled if you say Y here. 393506f1d07SSam Ravnborg 394395cf969SPaul Bolle See also <file:Documentation/x86/i386/IO-APIC.txt>, 395c9525a3fSBenjamin Peterson <file:Documentation/lockup-watchdogs.txt> and the SMP-HOWTO available at 396506f1d07SSam Ravnborg <http://www.tldp.org/docs.html#howto>. 397506f1d07SSam Ravnborg 398506f1d07SSam Ravnborg If you don't know what to do here, say N. 399506f1d07SSam Ravnborg 4009def39beSJosh Triplettconfig X86_FEATURE_NAMES 4019def39beSJosh Triplett bool "Processor feature human-readable names" if EMBEDDED 4029def39beSJosh Triplett default y 4039def39beSJosh Triplett ---help--- 4049def39beSJosh Triplett This option compiles in a table of x86 feature bits and corresponding 4059def39beSJosh Triplett names. This is required to support /proc/cpuinfo and a few kernel 4069def39beSJosh Triplett messages. You can disable this to save space, at the expense of 4079def39beSJosh Triplett making those few kernel messages show numeric feature bits instead. 4089def39beSJosh Triplett 4099def39beSJosh Triplett If in doubt, say Y. 4109def39beSJosh Triplett 41106cd9a7dSYinghai Luconfig X86_X2APIC 41206cd9a7dSYinghai Lu bool "Support x2apic" 41319e3d60dSJan Kiszka depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST) 41406cd9a7dSYinghai Lu ---help--- 41506cd9a7dSYinghai Lu This enables x2apic support on CPUs that have this feature. 41606cd9a7dSYinghai Lu 41706cd9a7dSYinghai Lu This allows 32-bit apic IDs (so it can support very large systems), 41806cd9a7dSYinghai Lu and accesses the local apic via MSRs not via mmio. 41906cd9a7dSYinghai Lu 42006cd9a7dSYinghai Lu If you don't know what to do here, say N. 42106cd9a7dSYinghai Lu 4226695c85bSYinghai Luconfig X86_MPPARSE 4236e87f9b7SBin Gao bool "Enable MPS table" if ACPI || SFI 4247a527688SJan Beulich default y 4255ab74722SIngo Molnar depends on X86_LOCAL_APIC 4268f9ca475SIngo Molnar ---help--- 4276695c85bSYinghai Lu For old smp systems that do not have proper acpi support. Newer systems 4286695c85bSYinghai Lu (esp with 64bit cpus) with acpi support, MADT and DSDT will override it 4296695c85bSYinghai Lu 430ddd70cf9SJun Nakajimaconfig GOLDFISH 431ddd70cf9SJun Nakajima def_bool y 432ddd70cf9SJun Nakajima depends on X86_GOLDFISH 433ddd70cf9SJun Nakajima 43476b04384SDavid Woodhouseconfig RETPOLINE 43576b04384SDavid Woodhouse bool "Avoid speculative indirect branches in kernel" 43676b04384SDavid Woodhouse default y 437d5028ba8SPeter Zijlstra select STACK_VALIDATION if HAVE_STACK_VALIDATION 43876b04384SDavid Woodhouse help 43976b04384SDavid Woodhouse Compile kernel with the retpoline compiler options to guard against 44076b04384SDavid Woodhouse kernel-to-user data leaks by avoiding speculative indirect 44176b04384SDavid Woodhouse branches. Requires a compiler with -mindirect-branch=thunk-extern 44276b04384SDavid Woodhouse support for full protection. The kernel may run slower. 44376b04384SDavid Woodhouse 444e6d42931SJohannes Weinerconfig X86_CPU_RESCTRL 445e6d42931SJohannes Weiner bool "x86 CPU resource control support" 4466fe07ce3SBabu Moger depends on X86 && (CPU_SUP_INTEL || CPU_SUP_AMD) 44759fe5a77SThomas Gleixner select KERNFS 44878e99b4aSFenghua Yu help 449e6d42931SJohannes Weiner Enable x86 CPU resource control support. 4506fe07ce3SBabu Moger 4516fe07ce3SBabu Moger Provide support for the allocation and monitoring of system resources 4526fe07ce3SBabu Moger usage by the CPU. 4536fe07ce3SBabu Moger 4546fe07ce3SBabu Moger Intel calls this Intel Resource Director Technology 4556fe07ce3SBabu Moger (Intel(R) RDT). More information about RDT can be found in the 4566fe07ce3SBabu Moger Intel x86 Architecture Software Developer Manual. 4576fe07ce3SBabu Moger 4586fe07ce3SBabu Moger AMD calls this AMD Platform Quality of Service (AMD QoS). 4596fe07ce3SBabu Moger More information about AMD QoS can be found in the AMD64 Technology 4606fe07ce3SBabu Moger Platform Quality of Service Extensions manual. 46178e99b4aSFenghua Yu 46278e99b4aSFenghua Yu Say N if unsure. 46378e99b4aSFenghua Yu 4648425091fSRavikiran G Thirumalaiif X86_32 465a0d0bb4dSRandy Dunlapconfig X86_BIGSMP 466a0d0bb4dSRandy Dunlap bool "Support for big SMP systems with more than 8 CPUs" 467a0d0bb4dSRandy Dunlap depends on SMP 468a0d0bb4dSRandy Dunlap ---help--- 469a0d0bb4dSRandy Dunlap This option is needed for the systems that have more than 8 CPUs 470a0d0bb4dSRandy Dunlap 471c5c606d9SRavikiran G Thirumalaiconfig X86_EXTENDED_PLATFORM 472c5c606d9SRavikiran G Thirumalai bool "Support for extended (non-PC) x86 platforms" 473c5c606d9SRavikiran G Thirumalai default y 4748f9ca475SIngo Molnar ---help--- 47506ac8346SIngo Molnar If you disable this option then the kernel will only support 47606ac8346SIngo Molnar standard PC platforms. (which covers the vast majority of 47706ac8346SIngo Molnar systems out there.) 47806ac8346SIngo Molnar 4798425091fSRavikiran G Thirumalai If you enable this option then you'll be able to select support 4808425091fSRavikiran G Thirumalai for the following (non-PC) 32 bit x86 platforms: 481cb7b8023SBen Hutchings Goldfish (Android emulator) 4828425091fSRavikiran G Thirumalai AMD Elan 4838425091fSRavikiran G Thirumalai RDC R-321x SoC 4848425091fSRavikiran G Thirumalai SGI 320/540 (Visual Workstation) 48583125a3aSAlessandro Rubini STA2X11-based (e.g. Northville) 4863f4110a4SThomas Gleixner Moorestown MID devices 48706ac8346SIngo Molnar 48806ac8346SIngo Molnar If you have one of these systems, or if you want to build a 48906ac8346SIngo Molnar generic distribution kernel, say Y here - otherwise say N. 4908425091fSRavikiran G Thirumalaiendif 49106ac8346SIngo Molnar 4928425091fSRavikiran G Thirumalaiif X86_64 4938425091fSRavikiran G Thirumalaiconfig X86_EXTENDED_PLATFORM 4948425091fSRavikiran G Thirumalai bool "Support for extended (non-PC) x86 platforms" 4958425091fSRavikiran G Thirumalai default y 4968425091fSRavikiran G Thirumalai ---help--- 4978425091fSRavikiran G Thirumalai If you disable this option then the kernel will only support 4988425091fSRavikiran G Thirumalai standard PC platforms. (which covers the vast majority of 4998425091fSRavikiran G Thirumalai systems out there.) 5008425091fSRavikiran G Thirumalai 5018425091fSRavikiran G Thirumalai If you enable this option then you'll be able to select support 5028425091fSRavikiran G Thirumalai for the following (non-PC) 64 bit x86 platforms: 50344b111b5SSteffen Persvold Numascale NumaChip 5048425091fSRavikiran G Thirumalai ScaleMP vSMP 5058425091fSRavikiran G Thirumalai SGI Ultraviolet 5068425091fSRavikiran G Thirumalai 5078425091fSRavikiran G Thirumalai If you have one of these systems, or if you want to build a 5088425091fSRavikiran G Thirumalai generic distribution kernel, say Y here - otherwise say N. 5098425091fSRavikiran G Thirumalaiendif 510c5c606d9SRavikiran G Thirumalai# This is an alphabetically sorted list of 64 bit extended platforms 511c5c606d9SRavikiran G Thirumalai# Please maintain the alphabetic order if and when there are additions 51244b111b5SSteffen Persvoldconfig X86_NUMACHIP 51344b111b5SSteffen Persvold bool "Numascale NumaChip" 51444b111b5SSteffen Persvold depends on X86_64 51544b111b5SSteffen Persvold depends on X86_EXTENDED_PLATFORM 51644b111b5SSteffen Persvold depends on NUMA 51744b111b5SSteffen Persvold depends on SMP 51844b111b5SSteffen Persvold depends on X86_X2APIC 519f9726bfdSDaniel J Blueman depends on PCI_MMCONFIG 52044b111b5SSteffen Persvold ---help--- 52144b111b5SSteffen Persvold Adds support for Numascale NumaChip large-SMP systems. Needed to 52244b111b5SSteffen Persvold enable more than ~168 cores. 52344b111b5SSteffen Persvold If you don't have one of these, you should say N here. 52403b48632SNick Piggin 5256a48565eSIngo Molnarconfig X86_VSMP 526c5c606d9SRavikiran G Thirumalai bool "ScaleMP vSMP" 5276276a074SBorislav Petkov select HYPERVISOR_GUEST 5286a48565eSIngo Molnar select PARAVIRT 5296a48565eSIngo Molnar depends on X86_64 && PCI 530c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 531ead91d4bSShai Fultheim depends on SMP 5328f9ca475SIngo Molnar ---help--- 5336a48565eSIngo Molnar Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is 5346a48565eSIngo Molnar supposed to run on these EM64T-based machines. Only choose this option 5356a48565eSIngo Molnar if you have one of these machines. 5366a48565eSIngo Molnar 537c5c606d9SRavikiran G Thirumalaiconfig X86_UV 538c5c606d9SRavikiran G Thirumalai bool "SGI Ultraviolet" 539c5c606d9SRavikiran G Thirumalai depends on X86_64 540c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 54154c28d29SJack Steiner depends on NUMA 5421ecb4ae5SAndrew Morton depends on EFI 5439d6c26e7SSuresh Siddha depends on X86_X2APIC 5441222e564SIngo Molnar depends on PCI 545c5c606d9SRavikiran G Thirumalai ---help--- 546c5c606d9SRavikiran G Thirumalai This option is needed in order to support SGI Ultraviolet systems. 547c5c606d9SRavikiran G Thirumalai If you don't have one of these, you should say N here. 548c5c606d9SRavikiran G Thirumalai 549c5c606d9SRavikiran G Thirumalai# Following is an alphabetically sorted list of 32 bit extended platforms 550c5c606d9SRavikiran G Thirumalai# Please maintain the alphabetic order if and when there are additions 551506f1d07SSam Ravnborg 552ddd70cf9SJun Nakajimaconfig X86_GOLDFISH 553ddd70cf9SJun Nakajima bool "Goldfish (Virtual Platform)" 554cb7b8023SBen Hutchings depends on X86_EXTENDED_PLATFORM 555ddd70cf9SJun Nakajima ---help--- 556ddd70cf9SJun Nakajima Enable support for the Goldfish virtual platform used primarily 557ddd70cf9SJun Nakajima for Android development. Unless you are building for the Android 558ddd70cf9SJun Nakajima Goldfish emulator say N here. 559ddd70cf9SJun Nakajima 560c751e17bSThomas Gleixnerconfig X86_INTEL_CE 561c751e17bSThomas Gleixner bool "CE4100 TV platform" 562c751e17bSThomas Gleixner depends on PCI 563c751e17bSThomas Gleixner depends on PCI_GODIRECT 5646084a6e2SJiang Liu depends on X86_IO_APIC 565c751e17bSThomas Gleixner depends on X86_32 566c751e17bSThomas Gleixner depends on X86_EXTENDED_PLATFORM 56737bc9f50SDirk Brandewie select X86_REBOOTFIXUPS 568da6b737bSSebastian Andrzej Siewior select OF 569da6b737bSSebastian Andrzej Siewior select OF_EARLY_FLATTREE 570c751e17bSThomas Gleixner ---help--- 571c751e17bSThomas Gleixner Select for the Intel CE media processor (CE4100) SOC. 572c751e17bSThomas Gleixner This option compiles in support for the CE4100 SOC for settop 573c751e17bSThomas Gleixner boxes and media devices. 574c751e17bSThomas Gleixner 5754cb9b00fSDavid Cohenconfig X86_INTEL_MID 57643605ef1SAlan Cox bool "Intel MID platform support" 57743605ef1SAlan Cox depends on X86_EXTENDED_PLATFORM 578edc6bc78SDavid Cohen depends on X86_PLATFORM_DEVICES 5791ea7c673SAlan Cox depends on PCI 5803fda5bb4SAndy Shevchenko depends on X86_64 || (PCI_GOANY && X86_32) 5811ea7c673SAlan Cox depends on X86_IO_APIC 5827c9c3a1eSAlan Cox select SFI 5834cb9b00fSDavid Cohen select I2C 5847c9c3a1eSAlan Cox select DW_APB_TIMER 5851ea7c673SAlan Cox select APB_TIMER 5861ea7c673SAlan Cox select INTEL_SCU_IPC 58715a713dfSMika Westerberg select MFD_INTEL_MSIC 5881ea7c673SAlan Cox ---help--- 5894cb9b00fSDavid Cohen Select to build a kernel capable of supporting Intel MID (Mobile 5904cb9b00fSDavid Cohen Internet Device) platform systems which do not have the PCI legacy 5914cb9b00fSDavid Cohen interfaces. If you are building for a PC class system say N here. 5921ea7c673SAlan Cox 5934cb9b00fSDavid Cohen Intel MID platforms are based on an Intel processor and chipset which 5944cb9b00fSDavid Cohen consume less power than most of the x86 derivatives. 59543605ef1SAlan Cox 5968bbc2a13SBryan O'Donoghueconfig X86_INTEL_QUARK 5978bbc2a13SBryan O'Donoghue bool "Intel Quark platform support" 5988bbc2a13SBryan O'Donoghue depends on X86_32 5998bbc2a13SBryan O'Donoghue depends on X86_EXTENDED_PLATFORM 6008bbc2a13SBryan O'Donoghue depends on X86_PLATFORM_DEVICES 6018bbc2a13SBryan O'Donoghue depends on X86_TSC 6028bbc2a13SBryan O'Donoghue depends on PCI 6038bbc2a13SBryan O'Donoghue depends on PCI_GOANY 6048bbc2a13SBryan O'Donoghue depends on X86_IO_APIC 6058bbc2a13SBryan O'Donoghue select IOSF_MBI 6068bbc2a13SBryan O'Donoghue select INTEL_IMR 6079ab6eb51SAndy Shevchenko select COMMON_CLK 6088bbc2a13SBryan O'Donoghue ---help--- 6098bbc2a13SBryan O'Donoghue Select to include support for Quark X1000 SoC. 6108bbc2a13SBryan O'Donoghue Say Y here if you have a Quark based system such as the Arduino 6118bbc2a13SBryan O'Donoghue compatible Intel Galileo. 6128bbc2a13SBryan O'Donoghue 6133d48aab1SMika Westerbergconfig X86_INTEL_LPSS 6143d48aab1SMika Westerberg bool "Intel Low Power Subsystem Support" 6155962dd22SSinan Kaya depends on X86 && ACPI && PCI 6163d48aab1SMika Westerberg select COMMON_CLK 6170f531431SMathias Nyman select PINCTRL 618eebb3e8dSAndy Shevchenko select IOSF_MBI 6193d48aab1SMika Westerberg ---help--- 6203d48aab1SMika Westerberg Select to build support for Intel Low Power Subsystem such as 6213d48aab1SMika Westerberg found on Intel Lynxpoint PCH. Selecting this option enables 6220f531431SMathias Nyman things like clock tree (common clock framework) and pincontrol 6230f531431SMathias Nyman which are needed by the LPSS peripheral drivers. 6243d48aab1SMika Westerberg 62592082a88SKen Xueconfig X86_AMD_PLATFORM_DEVICE 62692082a88SKen Xue bool "AMD ACPI2Platform devices support" 62792082a88SKen Xue depends on ACPI 62892082a88SKen Xue select COMMON_CLK 62992082a88SKen Xue select PINCTRL 63092082a88SKen Xue ---help--- 63192082a88SKen Xue Select to interpret AMD specific ACPI device to platform device 63292082a88SKen Xue such as I2C, UART, GPIO found on AMD Carrizo and later chipsets. 63392082a88SKen Xue I2C and UART depend on COMMON_CLK to set clock. GPIO driver is 63492082a88SKen Xue implemented under PINCTRL subsystem. 63592082a88SKen Xue 636ced3ce76SDavid E. Boxconfig IOSF_MBI 637ced3ce76SDavid E. Box tristate "Intel SoC IOSF Sideband support for SoC platforms" 638ced3ce76SDavid E. Box depends on PCI 639ced3ce76SDavid E. Box ---help--- 640ced3ce76SDavid E. Box This option enables sideband register access support for Intel SoC 641ced3ce76SDavid E. Box platforms. On these platforms the IOSF sideband is used in lieu of 642ced3ce76SDavid E. Box MSR's for some register accesses, mostly but not limited to thermal 643ced3ce76SDavid E. Box and power. Drivers may query the availability of this device to 644ced3ce76SDavid E. Box determine if they need the sideband in order to work on these 645ced3ce76SDavid E. Box platforms. The sideband is available on the following SoC products. 646ced3ce76SDavid E. Box This list is not meant to be exclusive. 647ced3ce76SDavid E. Box - BayTrail 648ced3ce76SDavid E. Box - Braswell 649ced3ce76SDavid E. Box - Quark 650ced3ce76SDavid E. Box 651ced3ce76SDavid E. Box You should say Y if you are running a kernel on one of these SoC's. 652ced3ce76SDavid E. Box 653ed2226bdSDavid E. Boxconfig IOSF_MBI_DEBUG 654ed2226bdSDavid E. Box bool "Enable IOSF sideband access through debugfs" 655ed2226bdSDavid E. Box depends on IOSF_MBI && DEBUG_FS 656ed2226bdSDavid E. Box ---help--- 657ed2226bdSDavid E. Box Select this option to expose the IOSF sideband access registers (MCR, 658ed2226bdSDavid E. Box MDR, MCRX) through debugfs to write and read register information from 659ed2226bdSDavid E. Box different units on the SoC. This is most useful for obtaining device 660ed2226bdSDavid E. Box state information for debug and analysis. As this is a general access 661ed2226bdSDavid E. Box mechanism, users of this option would have specific knowledge of the 662ed2226bdSDavid E. Box device they want to access. 663ed2226bdSDavid E. Box 664ed2226bdSDavid E. Box If you don't require the option or are in doubt, say N. 665ed2226bdSDavid E. Box 666c5c606d9SRavikiran G Thirumalaiconfig X86_RDC321X 667c5c606d9SRavikiran G Thirumalai bool "RDC R-321x SoC" 668506f1d07SSam Ravnborg depends on X86_32 669c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 670c5c606d9SRavikiran G Thirumalai select M486 671c5c606d9SRavikiran G Thirumalai select X86_REBOOTFIXUPS 672c5c606d9SRavikiran G Thirumalai ---help--- 673c5c606d9SRavikiran G Thirumalai This option is needed for RDC R-321x system-on-chip, also known 674c5c606d9SRavikiran G Thirumalai as R-8610-(G). 675c5c606d9SRavikiran G Thirumalai If you don't have one of these chips, you should say N here. 676c5c606d9SRavikiran G Thirumalai 677e0c7ae37SIngo Molnarconfig X86_32_NON_STANDARD 6789c398017SIngo Molnar bool "Support non-standard 32-bit SMP architectures" 6799c398017SIngo Molnar depends on X86_32 && SMP 680c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 6818f9ca475SIngo Molnar ---help--- 682b5660ba7SH. Peter Anvin This option compiles in the bigsmp and STA2X11 default 683b5660ba7SH. Peter Anvin subarchitectures. It is intended for a generic binary 684b5660ba7SH. Peter Anvin kernel. If you select them all, kernel will probe it one by 685b5660ba7SH. Peter Anvin one and will fallback to default. 686d49c4288SYinghai Lu 687c5c606d9SRavikiran G Thirumalai# Alphabetically sorted list of Non standard 32 bit platforms 688d49c4288SYinghai Lu 689d949f36fSLinus Torvaldsconfig X86_SUPPORTS_MEMORY_FAILURE 6906fc108a0SJan Beulich def_bool y 691d949f36fSLinus Torvalds # MCE code calls memory_failure(): 692d949f36fSLinus Torvalds depends on X86_MCE 693d949f36fSLinus Torvalds # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags: 694d949f36fSLinus Torvalds # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH: 695d949f36fSLinus Torvalds depends on X86_64 || !SPARSEMEM 696d949f36fSLinus Torvalds select ARCH_SUPPORTS_MEMORY_FAILURE 697d949f36fSLinus Torvalds 69883125a3aSAlessandro Rubiniconfig STA2X11 69983125a3aSAlessandro Rubini bool "STA2X11 Companion Chip Support" 70083125a3aSAlessandro Rubini depends on X86_32_NON_STANDARD && PCI 701b6e05477SChristoph Hellwig select ARCH_HAS_PHYS_TO_DMA 70283125a3aSAlessandro Rubini select SWIOTLB 70383125a3aSAlessandro Rubini select MFD_STA2X11 7040145071bSLinus Walleij select GPIOLIB 70583125a3aSAlessandro Rubini ---help--- 70683125a3aSAlessandro Rubini This adds support for boards based on the STA2X11 IO-Hub, 70783125a3aSAlessandro Rubini a.k.a. "ConneXt". The chip is used in place of the standard 70883125a3aSAlessandro Rubini PC chipset, so all "standard" peripherals are missing. If this 70983125a3aSAlessandro Rubini option is selected the kernel will still be able to boot on 71083125a3aSAlessandro Rubini standard PC machines. 71183125a3aSAlessandro Rubini 71282148d1dSShérabconfig X86_32_IRIS 71382148d1dSShérab tristate "Eurobraille/Iris poweroff module" 71482148d1dSShérab depends on X86_32 71582148d1dSShérab ---help--- 71682148d1dSShérab The Iris machines from EuroBraille do not have APM or ACPI support 71782148d1dSShérab to shut themselves down properly. A special I/O sequence is 71882148d1dSShérab needed to do so, which is what this module does at 71982148d1dSShérab kernel shutdown. 72082148d1dSShérab 72182148d1dSShérab This is only for Iris machines from EuroBraille. 72282148d1dSShérab 72382148d1dSShérab If unused, say N. 72482148d1dSShérab 725ae1e9130SIngo Molnarconfig SCHED_OMIT_FRAME_POINTER 7263c2362e6SHarvey Harrison def_bool y 7273c2362e6SHarvey Harrison prompt "Single-depth WCHAN output" 728a87d0914SKen Chen depends on X86 7298f9ca475SIngo Molnar ---help--- 730506f1d07SSam Ravnborg Calculate simpler /proc/<PID>/wchan values. If this option 731506f1d07SSam Ravnborg is disabled then wchan values will recurse back to the 732506f1d07SSam Ravnborg caller function. This provides more accurate wchan values, 733506f1d07SSam Ravnborg at the expense of slightly more scheduling overhead. 734506f1d07SSam Ravnborg 735506f1d07SSam Ravnborg If in doubt, say "Y". 736506f1d07SSam Ravnborg 7376276a074SBorislav Petkovmenuconfig HYPERVISOR_GUEST 7386276a074SBorislav Petkov bool "Linux guest support" 7398f9ca475SIngo Molnar ---help--- 7406276a074SBorislav Petkov Say Y here to enable options for running Linux under various hyper- 7416276a074SBorislav Petkov visors. This option enables basic hypervisor detection and platform 7426276a074SBorislav Petkov setup. 743506f1d07SSam Ravnborg 7446276a074SBorislav Petkov If you say N, all options in this submenu will be skipped and 7456276a074SBorislav Petkov disabled, and Linux guest support won't be built in. 746506f1d07SSam Ravnborg 7476276a074SBorislav Petkovif HYPERVISOR_GUEST 748506f1d07SSam Ravnborg 749e61bd94aSEduardo Pereira Habkostconfig PARAVIRT 750e61bd94aSEduardo Pereira Habkost bool "Enable paravirtualization code" 7518f9ca475SIngo Molnar ---help--- 752e61bd94aSEduardo Pereira Habkost This changes the kernel so it can modify itself when it is run 753e61bd94aSEduardo Pereira Habkost under a hypervisor, potentially improving performance significantly 754e61bd94aSEduardo Pereira Habkost over full virtualization. However, when run without a hypervisor 755e61bd94aSEduardo Pereira Habkost the kernel is theoretically slower and slightly larger. 756e61bd94aSEduardo Pereira Habkost 757c00a280aSJuergen Grossconfig PARAVIRT_XXL 758c00a280aSJuergen Gross bool 759c00a280aSJuergen Gross 7606276a074SBorislav Petkovconfig PARAVIRT_DEBUG 7616276a074SBorislav Petkov bool "paravirt-ops debugging" 7626276a074SBorislav Petkov depends on PARAVIRT && DEBUG_KERNEL 7636276a074SBorislav Petkov ---help--- 7646276a074SBorislav Petkov Enable to debug paravirt_ops internals. Specifically, BUG if 7656276a074SBorislav Petkov a paravirt_op is missing when it is called. 7666276a074SBorislav Petkov 767b4ecc126SJeremy Fitzhardingeconfig PARAVIRT_SPINLOCKS 768b4ecc126SJeremy Fitzhardinge bool "Paravirtualization layer for spinlocks" 7696ea30386SKees Cook depends on PARAVIRT && SMP 770b4ecc126SJeremy Fitzhardinge ---help--- 771b4ecc126SJeremy Fitzhardinge Paravirtualized spinlocks allow a pvops backend to replace the 772b4ecc126SJeremy Fitzhardinge spinlock implementation with something virtualization-friendly 773b4ecc126SJeremy Fitzhardinge (for example, block the virtual CPU rather than spinning). 774b4ecc126SJeremy Fitzhardinge 7754c4e4f61SRaghavendra K T It has a minimal impact on native kernels and gives a nice performance 7764c4e4f61SRaghavendra K T benefit on paravirtualized KVM / Xen kernels. 777b4ecc126SJeremy Fitzhardinge 7784c4e4f61SRaghavendra K T If you are unsure how to answer this question, answer Y. 779b4ecc126SJeremy Fitzhardinge 7806276a074SBorislav Petkovsource "arch/x86/xen/Kconfig" 7816276a074SBorislav Petkov 7826276a074SBorislav Petkovconfig KVM_GUEST 7836276a074SBorislav Petkov bool "KVM Guest support (including kvmclock)" 7846276a074SBorislav Petkov depends on PARAVIRT 7856276a074SBorislav Petkov select PARAVIRT_CLOCK 7866276a074SBorislav Petkov default y 7876276a074SBorislav Petkov ---help--- 7886276a074SBorislav Petkov This option enables various optimizations for running under the KVM 7896276a074SBorislav Petkov hypervisor. It includes a paravirtualized clock, so that instead 7906276a074SBorislav Petkov of relying on a PIT (or probably other) emulation by the 7916276a074SBorislav Petkov underlying device model, the host provides the guest with 7926276a074SBorislav Petkov timing infrastructure such as time of day, and system time 7936276a074SBorislav Petkov 7947733607fSMaran Wilsonconfig PVH 7957733607fSMaran Wilson bool "Support for running PVH guests" 7967733607fSMaran Wilson ---help--- 7977733607fSMaran Wilson This option enables the PVH entry point for guest virtual machines 7987733607fSMaran Wilson as specified in the x86/HVM direct boot ABI. 7997733607fSMaran Wilson 8001e20eb85SSrivatsa Vaddagiriconfig KVM_DEBUG_FS 8011e20eb85SSrivatsa Vaddagiri bool "Enable debug information for KVM Guests in debugfs" 8021e20eb85SSrivatsa Vaddagiri depends on KVM_GUEST && DEBUG_FS 8031e20eb85SSrivatsa Vaddagiri ---help--- 8041e20eb85SSrivatsa Vaddagiri This option enables collection of various statistics for KVM guest. 8051e20eb85SSrivatsa Vaddagiri Statistics are displayed in debugfs filesystem. Enabling this option 8061e20eb85SSrivatsa Vaddagiri may incur significant overhead. 8071e20eb85SSrivatsa Vaddagiri 8086276a074SBorislav Petkovconfig PARAVIRT_TIME_ACCOUNTING 8096276a074SBorislav Petkov bool "Paravirtual steal time accounting" 8106276a074SBorislav Petkov depends on PARAVIRT 8116276a074SBorislav Petkov ---help--- 8126276a074SBorislav Petkov Select this option to enable fine granularity task steal time 8136276a074SBorislav Petkov accounting. Time spent executing other tasks in parallel with 8146276a074SBorislav Petkov the current vCPU is discounted from the vCPU power. To account for 8156276a074SBorislav Petkov that, there can be a small performance impact. 8166276a074SBorislav Petkov 8176276a074SBorislav Petkov If in doubt, say N here. 8186276a074SBorislav Petkov 8197af192c9SGerd Hoffmannconfig PARAVIRT_CLOCK 8207af192c9SGerd Hoffmann bool 8217af192c9SGerd Hoffmann 8224a362601SJan Kiszkaconfig JAILHOUSE_GUEST 8234a362601SJan Kiszka bool "Jailhouse non-root cell support" 824abde587bSArnd Bergmann depends on X86_64 && PCI 82587e65d05SJan Kiszka select X86_PM_TIMER 8264a362601SJan Kiszka ---help--- 8274a362601SJan Kiszka This option allows to run Linux as guest in a Jailhouse non-root 8284a362601SJan Kiszka cell. You can leave this option disabled if you only want to start 8294a362601SJan Kiszka Jailhouse and run Linux afterwards in the root cell. 8304a362601SJan Kiszka 8316276a074SBorislav Petkovendif #HYPERVISOR_GUEST 83297349135SJeremy Fitzhardinge 833506f1d07SSam Ravnborgsource "arch/x86/Kconfig.cpu" 834506f1d07SSam Ravnborg 835506f1d07SSam Ravnborgconfig HPET_TIMER 8363c2362e6SHarvey Harrison def_bool X86_64 837506f1d07SSam Ravnborg prompt "HPET Timer Support" if X86_32 8388f9ca475SIngo Molnar ---help--- 839506f1d07SSam Ravnborg Use the IA-PC HPET (High Precision Event Timer) to manage 840506f1d07SSam Ravnborg time in preference to the PIT and RTC, if a HPET is 841506f1d07SSam Ravnborg present. 842506f1d07SSam Ravnborg HPET is the next generation timer replacing legacy 8254s. 843506f1d07SSam Ravnborg The HPET provides a stable time base on SMP 844506f1d07SSam Ravnborg systems, unlike the TSC, but it is more expensive to access, 8454e7f9df2SMichael S. Tsirkin as it is off-chip. The interface used is documented 8464e7f9df2SMichael S. Tsirkin in the HPET spec, revision 1. 847506f1d07SSam Ravnborg 848506f1d07SSam Ravnborg You can safely choose Y here. However, HPET will only be 849506f1d07SSam Ravnborg activated if the platform and the BIOS support this feature. 850506f1d07SSam Ravnborg Otherwise the 8254 will be used for timing services. 851506f1d07SSam Ravnborg 852506f1d07SSam Ravnborg Choose N to continue using the legacy 8254 timer. 853506f1d07SSam Ravnborg 854506f1d07SSam Ravnborgconfig HPET_EMULATE_RTC 8553c2362e6SHarvey Harrison def_bool y 8569d8af78bSBernhard Walle depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y) 857506f1d07SSam Ravnborg 858bb24c471SJacob Panconfig APB_TIMER 859933b9463SAlan Cox def_bool y if X86_INTEL_MID 860933b9463SAlan Cox prompt "Intel MID APB Timer Support" if X86_INTEL_MID 86106c3df49SJamie Iles select DW_APB_TIMER 862a0c3832aSAlan Cox depends on X86_INTEL_MID && SFI 863bb24c471SJacob Pan help 864bb24c471SJacob Pan APB timer is the replacement for 8254, HPET on X86 MID platforms. 865bb24c471SJacob Pan The APBT provides a stable time base on SMP 866bb24c471SJacob Pan systems, unlike the TSC, but it is more expensive to access, 867bb24c471SJacob Pan as it is off-chip. APB timers are always running regardless of CPU 868bb24c471SJacob Pan C states, they are used as per CPU clockevent device when possible. 869bb24c471SJacob Pan 8706a108a14SDavid Rientjes# Mark as expert because too many people got it wrong. 871506f1d07SSam Ravnborg# The code disables itself when not needed. 8727ae9392cSThomas Petazzoniconfig DMI 8737ae9392cSThomas Petazzoni default y 874cf074402SArd Biesheuvel select DMI_SCAN_MACHINE_NON_EFI_FALLBACK 8756a108a14SDavid Rientjes bool "Enable DMI scanning" if EXPERT 8768f9ca475SIngo Molnar ---help--- 8777ae9392cSThomas Petazzoni Enabled scanning of DMI to identify machine quirks. Say Y 8787ae9392cSThomas Petazzoni here unless you have verified that your setup is not 8797ae9392cSThomas Petazzoni affected by entries in the DMI blacklist. Required by PNP 8807ae9392cSThomas Petazzoni BIOS code. 8817ae9392cSThomas Petazzoni 882506f1d07SSam Ravnborgconfig GART_IOMMU 88338901f1cSAndi Kleen bool "Old AMD GART IOMMU support" 884a4ce5a48SChristoph Hellwig select IOMMU_HELPER 885506f1d07SSam Ravnborg select SWIOTLB 88623ac4ae8SAndreas Herrmann depends on X86_64 && PCI && AMD_NB 8878f9ca475SIngo Molnar ---help--- 888ced3c42cSIngo Molnar Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron 889ced3c42cSIngo Molnar GART based hardware IOMMUs. 890ced3c42cSIngo Molnar 891ced3c42cSIngo Molnar The GART supports full DMA access for devices with 32-bit access 892ced3c42cSIngo Molnar limitations, on systems with more than 3 GB. This is usually needed 893ced3c42cSIngo Molnar for USB, sound, many IDE/SATA chipsets and some other devices. 894ced3c42cSIngo Molnar 895ced3c42cSIngo Molnar Newer systems typically have a modern AMD IOMMU, supported via 896ced3c42cSIngo Molnar the CONFIG_AMD_IOMMU=y config option. 897ced3c42cSIngo Molnar 898ced3c42cSIngo Molnar In normal configurations this driver is only active when needed: 899ced3c42cSIngo Molnar there's more than 3 GB of memory and the system contains a 900ced3c42cSIngo Molnar 32-bit limited device. 901ced3c42cSIngo Molnar 902ced3c42cSIngo Molnar If unsure, say Y. 903506f1d07SSam Ravnborg 904506f1d07SSam Ravnborgconfig CALGARY_IOMMU 905506f1d07SSam Ravnborg bool "IBM Calgary IOMMU support" 906a4ce5a48SChristoph Hellwig select IOMMU_HELPER 907506f1d07SSam Ravnborg select SWIOTLB 9086ea30386SKees Cook depends on X86_64 && PCI 9098f9ca475SIngo Molnar ---help--- 910506f1d07SSam Ravnborg Support for hardware IOMMUs in IBM's xSeries x366 and x460 911506f1d07SSam Ravnborg systems. Needed to run systems with more than 3GB of memory 912506f1d07SSam Ravnborg properly with 32-bit PCI devices that do not support DAC 913506f1d07SSam Ravnborg (Double Address Cycle). Calgary also supports bus level 914506f1d07SSam Ravnborg isolation, where all DMAs pass through the IOMMU. This 915506f1d07SSam Ravnborg prevents them from going anywhere except their intended 916506f1d07SSam Ravnborg destination. This catches hard-to-find kernel bugs and 917506f1d07SSam Ravnborg mis-behaving drivers and devices that do not use the DMA-API 918506f1d07SSam Ravnborg properly to set up their DMA buffers. The IOMMU can be 919506f1d07SSam Ravnborg turned off at boot time with the iommu=off parameter. 920506f1d07SSam Ravnborg Normally the kernel will make the right choice by itself. 921506f1d07SSam Ravnborg If unsure, say Y. 922506f1d07SSam Ravnborg 923506f1d07SSam Ravnborgconfig CALGARY_IOMMU_ENABLED_BY_DEFAULT 9243c2362e6SHarvey Harrison def_bool y 9253c2362e6SHarvey Harrison prompt "Should Calgary be enabled by default?" 926506f1d07SSam Ravnborg depends on CALGARY_IOMMU 9278f9ca475SIngo Molnar ---help--- 928506f1d07SSam Ravnborg Should Calgary be enabled by default? if you choose 'y', Calgary 929506f1d07SSam Ravnborg will be used (if it exists). If you choose 'n', Calgary will not be 930506f1d07SSam Ravnborg used even if it exists. If you choose 'n' and would like to use 931506f1d07SSam Ravnborg Calgary anyway, pass 'iommu=calgary' on the kernel command line. 932506f1d07SSam Ravnborg If unsure, say Y. 933506f1d07SSam Ravnborg 9341184dc2fSMike Travisconfig MAXSMP 935ddb0c5a6SSamuel Thibault bool "Enable Maximum number of SMP Processors and NUMA Nodes" 9366ea30386SKees Cook depends on X86_64 && SMP && DEBUG_KERNEL 93736f5101aSMike Travis select CPUMASK_OFFSTACK 9388f9ca475SIngo Molnar ---help--- 939ddb0c5a6SSamuel Thibault Enable maximum number of CPUS and NUMA Nodes for this architecture. 9401184dc2fSMike Travis If unsure, say N. 941506f1d07SSam Ravnborg 942aec6487eSIngo Molnar# 943aec6487eSIngo Molnar# The maximum number of CPUs supported: 944aec6487eSIngo Molnar# 945aec6487eSIngo Molnar# The main config value is NR_CPUS, which defaults to NR_CPUS_DEFAULT, 946aec6487eSIngo Molnar# and which can be configured interactively in the 947aec6487eSIngo Molnar# [NR_CPUS_RANGE_BEGIN ... NR_CPUS_RANGE_END] range. 948aec6487eSIngo Molnar# 949aec6487eSIngo Molnar# The ranges are different on 32-bit and 64-bit kernels, depending on 950aec6487eSIngo Molnar# hardware capabilities and scalability features of the kernel. 951aec6487eSIngo Molnar# 952aec6487eSIngo Molnar# ( If MAXSMP is enabled we just use the highest possible value and disable 953aec6487eSIngo Molnar# interactive configuration. ) 954aec6487eSIngo Molnar# 955a0d0bb4dSRandy Dunlap 956aec6487eSIngo Molnarconfig NR_CPUS_RANGE_BEGIN 957a0d0bb4dSRandy Dunlap int 958aec6487eSIngo Molnar default NR_CPUS_RANGE_END if MAXSMP 959a0d0bb4dSRandy Dunlap default 1 if !SMP 960a0d0bb4dSRandy Dunlap default 2 961a0d0bb4dSRandy Dunlap 962aec6487eSIngo Molnarconfig NR_CPUS_RANGE_END 963a0d0bb4dSRandy Dunlap int 964a0d0bb4dSRandy Dunlap depends on X86_32 965aec6487eSIngo Molnar default 64 if SMP && X86_BIGSMP 966aec6487eSIngo Molnar default 8 if SMP && !X86_BIGSMP 967a0d0bb4dSRandy Dunlap default 1 if !SMP 968a0d0bb4dSRandy Dunlap 969aec6487eSIngo Molnarconfig NR_CPUS_RANGE_END 970a0d0bb4dSRandy Dunlap int 971a0d0bb4dSRandy Dunlap depends on X86_64 972aec6487eSIngo Molnar default 8192 if SMP && ( MAXSMP || CPUMASK_OFFSTACK) 973aec6487eSIngo Molnar default 512 if SMP && (!MAXSMP && !CPUMASK_OFFSTACK) 974a0d0bb4dSRandy Dunlap default 1 if !SMP 975aec6487eSIngo Molnar 976aec6487eSIngo Molnarconfig NR_CPUS_DEFAULT 977aec6487eSIngo Molnar int 978aec6487eSIngo Molnar depends on X86_32 979aec6487eSIngo Molnar default 32 if X86_BIGSMP 980aec6487eSIngo Molnar default 8 if SMP 981aec6487eSIngo Molnar default 1 if !SMP 982aec6487eSIngo Molnar 983aec6487eSIngo Molnarconfig NR_CPUS_DEFAULT 984aec6487eSIngo Molnar int 985aec6487eSIngo Molnar depends on X86_64 986a0d0bb4dSRandy Dunlap default 8192 if MAXSMP 987a0d0bb4dSRandy Dunlap default 64 if SMP 988aec6487eSIngo Molnar default 1 if !SMP 989a0d0bb4dSRandy Dunlap 990506f1d07SSam Ravnborgconfig NR_CPUS 99136f5101aSMike Travis int "Maximum number of CPUs" if SMP && !MAXSMP 992aec6487eSIngo Molnar range NR_CPUS_RANGE_BEGIN NR_CPUS_RANGE_END 993aec6487eSIngo Molnar default NR_CPUS_DEFAULT 9948f9ca475SIngo Molnar ---help--- 995506f1d07SSam Ravnborg This allows you to specify the maximum number of CPUs which this 996bb61ccc7SJosh Boyer kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum 997cad14bb9SKirill A. Shutemov supported value is 8192, otherwise the maximum value is 512. The 998506f1d07SSam Ravnborg minimum value which makes sense is 2. 999506f1d07SSam Ravnborg 1000aec6487eSIngo Molnar This is purely to save memory: each supported CPU adds about 8KB 1001aec6487eSIngo Molnar to the kernel image. 1002506f1d07SSam Ravnborg 1003506f1d07SSam Ravnborgconfig SCHED_SMT 1004dbe73364SThomas Gleixner def_bool y if SMP 1005506f1d07SSam Ravnborg 1006506f1d07SSam Ravnborgconfig SCHED_MC 10073c2362e6SHarvey Harrison def_bool y 10083c2362e6SHarvey Harrison prompt "Multi-core scheduler support" 1009c8e56d20SBorislav Petkov depends on SMP 10108f9ca475SIngo Molnar ---help--- 1011506f1d07SSam Ravnborg Multi-core scheduler support improves the CPU scheduler's decision 1012506f1d07SSam Ravnborg making when dealing with multi-core CPU chips at a cost of slightly 1013506f1d07SSam Ravnborg increased overhead in some places. If unsure say N here. 1014506f1d07SSam Ravnborg 1015de966cf4STim Chenconfig SCHED_MC_PRIO 1016de966cf4STim Chen bool "CPU core priorities scheduler support" 10170a21fc12SIngo Molnar depends on SCHED_MC && CPU_SUP_INTEL 10180a21fc12SIngo Molnar select X86_INTEL_PSTATE 10190a21fc12SIngo Molnar select CPU_FREQ 1020de966cf4STim Chen default y 10215e76b2abSTim Chen ---help--- 1022de966cf4STim Chen Intel Turbo Boost Max Technology 3.0 enabled CPUs have a 1023de966cf4STim Chen core ordering determined at manufacturing time, which allows 1024de966cf4STim Chen certain cores to reach higher turbo frequencies (when running 1025de966cf4STim Chen single threaded workloads) than others. 1026de966cf4STim Chen 1027de966cf4STim Chen Enabling this kernel feature teaches the scheduler about 1028de966cf4STim Chen the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the 1029de966cf4STim Chen scheduler's CPU selection logic accordingly, so that higher 1030de966cf4STim Chen overall system performance can be achieved. 1031de966cf4STim Chen 1032de966cf4STim Chen This feature will have no effect on CPUs without this feature. 1033de966cf4STim Chen 1034de966cf4STim Chen If unsure say Y here. 10355e76b2abSTim Chen 103630b8b006SThomas Gleixnerconfig UP_LATE_INIT 103730b8b006SThomas Gleixner def_bool y 1038ba360f88SThomas Gleixner depends on !SMP && X86_LOCAL_APIC 103930b8b006SThomas Gleixner 1040506f1d07SSam Ravnborgconfig X86_UP_APIC 104150849eefSJan Beulich bool "Local APIC support on uniprocessors" if !PCI_MSI 104250849eefSJan Beulich default PCI_MSI 104338a1dfdaSBryan O'Donoghue depends on X86_32 && !SMP && !X86_32_NON_STANDARD 10448f9ca475SIngo Molnar ---help--- 1045506f1d07SSam Ravnborg A local APIC (Advanced Programmable Interrupt Controller) is an 1046506f1d07SSam Ravnborg integrated interrupt controller in the CPU. If you have a single-CPU 1047506f1d07SSam Ravnborg system which has a processor with a local APIC, you can say Y here to 1048506f1d07SSam Ravnborg enable and use it. If you say Y here even though your machine doesn't 1049506f1d07SSam Ravnborg have a local APIC, then the kernel will still run with no slowdown at 1050506f1d07SSam Ravnborg all. The local APIC supports CPU-generated self-interrupts (timer, 1051506f1d07SSam Ravnborg performance counters), and the NMI watchdog which detects hard 1052506f1d07SSam Ravnborg lockups. 1053506f1d07SSam Ravnborg 1054506f1d07SSam Ravnborgconfig X86_UP_IOAPIC 1055506f1d07SSam Ravnborg bool "IO-APIC support on uniprocessors" 1056506f1d07SSam Ravnborg depends on X86_UP_APIC 10578f9ca475SIngo Molnar ---help--- 1058506f1d07SSam Ravnborg An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an 1059506f1d07SSam Ravnborg SMP-capable replacement for PC-style interrupt controllers. Most 1060506f1d07SSam Ravnborg SMP systems and many recent uniprocessor systems have one. 1061506f1d07SSam Ravnborg 1062506f1d07SSam Ravnborg If you have a single-CPU system with an IO-APIC, you can say Y here 1063506f1d07SSam Ravnborg to use it. If you say Y here even though your machine doesn't have 1064506f1d07SSam Ravnborg an IO-APIC, then the kernel will still run with no slowdown at all. 1065506f1d07SSam Ravnborg 1066506f1d07SSam Ravnborgconfig X86_LOCAL_APIC 10673c2362e6SHarvey Harrison def_bool y 10680dbc6078SThomas Petazzoni depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI 1069b5dc8e6cSJiang Liu select IRQ_DOMAIN_HIERARCHY 107052f518a3SJiang Liu select PCI_MSI_IRQ_DOMAIN if PCI_MSI 1071506f1d07SSam Ravnborg 1072506f1d07SSam Ravnborgconfig X86_IO_APIC 1073b1da1e71SJan Beulich def_bool y 1074b1da1e71SJan Beulich depends on X86_LOCAL_APIC || X86_UP_IOAPIC 1075506f1d07SSam Ravnborg 107641b9eb26SStefan Assmannconfig X86_REROUTE_FOR_BROKEN_BOOT_IRQS 107741b9eb26SStefan Assmann bool "Reroute for broken boot IRQs" 107841b9eb26SStefan Assmann depends on X86_IO_APIC 10798f9ca475SIngo Molnar ---help--- 108041b9eb26SStefan Assmann This option enables a workaround that fixes a source of 108141b9eb26SStefan Assmann spurious interrupts. This is recommended when threaded 108241b9eb26SStefan Assmann interrupt handling is used on systems where the generation of 108341b9eb26SStefan Assmann superfluous "boot interrupts" cannot be disabled. 108441b9eb26SStefan Assmann 108541b9eb26SStefan Assmann Some chipsets generate a legacy INTx "boot IRQ" when the IRQ 108641b9eb26SStefan Assmann entry in the chipset's IO-APIC is masked (as, e.g. the RT 108741b9eb26SStefan Assmann kernel does during interrupt handling). On chipsets where this 108841b9eb26SStefan Assmann boot IRQ generation cannot be disabled, this workaround keeps 108941b9eb26SStefan Assmann the original IRQ line masked so that only the equivalent "boot 109041b9eb26SStefan Assmann IRQ" is delivered to the CPUs. The workaround also tells the 109141b9eb26SStefan Assmann kernel to set up the IRQ handler on the boot IRQ line. In this 109241b9eb26SStefan Assmann way only one interrupt is delivered to the kernel. Otherwise 109341b9eb26SStefan Assmann the spurious second interrupt may cause the kernel to bring 109441b9eb26SStefan Assmann down (vital) interrupt lines. 109541b9eb26SStefan Assmann 109641b9eb26SStefan Assmann Only affects "broken" chipsets. Interrupt sharing may be 109741b9eb26SStefan Assmann increased on these systems. 109841b9eb26SStefan Assmann 1099506f1d07SSam Ravnborgconfig X86_MCE 1100bab9bc65SAndi Kleen bool "Machine Check / overheating reporting" 1101648ed940SChen, Gong select GENERIC_ALLOCATOR 1102e57dbaf7SBorislav Petkov default y 1103506f1d07SSam Ravnborg ---help--- 1104bab9bc65SAndi Kleen Machine Check support allows the processor to notify the 1105bab9bc65SAndi Kleen kernel if it detects a problem (e.g. overheating, data corruption). 1106506f1d07SSam Ravnborg The action the kernel takes depends on the severity of the problem, 1107bab9bc65SAndi Kleen ranging from warning messages to halting the machine. 11084efc0670SAndi Kleen 11095de97c9fSTony Luckconfig X86_MCELOG_LEGACY 11105de97c9fSTony Luck bool "Support for deprecated /dev/mcelog character device" 11115de97c9fSTony Luck depends on X86_MCE 11125de97c9fSTony Luck ---help--- 11135de97c9fSTony Luck Enable support for /dev/mcelog which is needed by the old mcelog 11145de97c9fSTony Luck userspace logging daemon. Consider switching to the new generation 11155de97c9fSTony Luck rasdaemon solution. 11165de97c9fSTony Luck 1117506f1d07SSam Ravnborgconfig X86_MCE_INTEL 11183c2362e6SHarvey Harrison def_bool y 11193c2362e6SHarvey Harrison prompt "Intel MCE features" 1120c1ebf835SAndi Kleen depends on X86_MCE && X86_LOCAL_APIC 11218f9ca475SIngo Molnar ---help--- 1122506f1d07SSam Ravnborg Additional support for intel specific MCE features such as 1123506f1d07SSam Ravnborg the thermal monitor. 1124506f1d07SSam Ravnborg 1125506f1d07SSam Ravnborgconfig X86_MCE_AMD 11263c2362e6SHarvey Harrison def_bool y 11273c2362e6SHarvey Harrison prompt "AMD MCE features" 1128f5382de9SYazen Ghannam depends on X86_MCE && X86_LOCAL_APIC && AMD_NB 11298f9ca475SIngo Molnar ---help--- 1130506f1d07SSam Ravnborg Additional support for AMD specific MCE features such as 1131506f1d07SSam Ravnborg the DRAM Error Threshold. 1132506f1d07SSam Ravnborg 11334efc0670SAndi Kleenconfig X86_ANCIENT_MCE 11346fc108a0SJan Beulich bool "Support for old Pentium 5 / WinChip machine checks" 1135c31d9633SAndi Kleen depends on X86_32 && X86_MCE 11364efc0670SAndi Kleen ---help--- 11374efc0670SAndi Kleen Include support for machine check handling on old Pentium 5 or WinChip 11385065a706SMasanari Iida systems. These typically need to be enabled explicitly on the command 11394efc0670SAndi Kleen line. 11404efc0670SAndi Kleen 1141b2762686SAndi Kleenconfig X86_MCE_THRESHOLD 1142b2762686SAndi Kleen depends on X86_MCE_AMD || X86_MCE_INTEL 11436fc108a0SJan Beulich def_bool y 1144b2762686SAndi Kleen 1145ea149b36SAndi Kleenconfig X86_MCE_INJECT 1146bc8e80d5SBorislav Petkov depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS 1147ea149b36SAndi Kleen tristate "Machine check injector support" 1148ea149b36SAndi Kleen ---help--- 1149ea149b36SAndi Kleen Provide support for injecting machine checks for testing purposes. 1150ea149b36SAndi Kleen If you don't know what a machine check is and you don't do kernel 1151ea149b36SAndi Kleen QA it is safe to say n. 1152ea149b36SAndi Kleen 11534efc0670SAndi Kleenconfig X86_THERMAL_VECTOR 11544efc0670SAndi Kleen def_bool y 11555bb38adcSAndi Kleen depends on X86_MCE_INTEL 11564efc0670SAndi Kleen 115707dc900eSPeter Zijlstrasource "arch/x86/events/Kconfig" 1158e633c65aSKan Liang 11595aef51c3SAndy Lutomirskiconfig X86_LEGACY_VM86 11601e642812SIngo Molnar bool "Legacy VM86 support" 1161506f1d07SSam Ravnborg depends on X86_32 11628f9ca475SIngo Molnar ---help--- 11635aef51c3SAndy Lutomirski This option allows user programs to put the CPU into V8086 11645aef51c3SAndy Lutomirski mode, which is an 80286-era approximation of 16-bit real mode. 11655aef51c3SAndy Lutomirski 11665aef51c3SAndy Lutomirski Some very old versions of X and/or vbetool require this option 11675aef51c3SAndy Lutomirski for user mode setting. Similarly, DOSEMU will use it if 11685aef51c3SAndy Lutomirski available to accelerate real mode DOS programs. However, any 11695aef51c3SAndy Lutomirski recent version of DOSEMU, X, or vbetool should be fully 11705aef51c3SAndy Lutomirski functional even without kernel VM86 support, as they will all 11711e642812SIngo Molnar fall back to software emulation. Nevertheless, if you are using 11721e642812SIngo Molnar a 16-bit DOS program where 16-bit performance matters, vm86 11731e642812SIngo Molnar mode might be faster than emulation and you might want to 11741e642812SIngo Molnar enable this option. 11755aef51c3SAndy Lutomirski 11761e642812SIngo Molnar Note that any app that works on a 64-bit kernel is unlikely to 11771e642812SIngo Molnar need this option, as 64-bit kernels don't, and can't, support 11781e642812SIngo Molnar V8086 mode. This option is also unrelated to 16-bit protected 11791e642812SIngo Molnar mode and is not needed to run most 16-bit programs under Wine. 11805aef51c3SAndy Lutomirski 11811e642812SIngo Molnar Enabling this option increases the complexity of the kernel 11821e642812SIngo Molnar and slows down exception handling a tiny bit. 11835aef51c3SAndy Lutomirski 11841e642812SIngo Molnar If unsure, say N here. 11855aef51c3SAndy Lutomirski 11865aef51c3SAndy Lutomirskiconfig VM86 11875aef51c3SAndy Lutomirski bool 11885aef51c3SAndy Lutomirski default X86_LEGACY_VM86 118934273f41SH. Peter Anvin 119034273f41SH. Peter Anvinconfig X86_16BIT 119134273f41SH. Peter Anvin bool "Enable support for 16-bit segments" if EXPERT 119234273f41SH. Peter Anvin default y 1193a5b9e5a2SAndy Lutomirski depends on MODIFY_LDT_SYSCALL 119434273f41SH. Peter Anvin ---help--- 119534273f41SH. Peter Anvin This option is required by programs like Wine to run 16-bit 119634273f41SH. Peter Anvin protected mode legacy code on x86 processors. Disabling 119734273f41SH. Peter Anvin this option saves about 300 bytes on i386, or around 6K text 119834273f41SH. Peter Anvin plus 16K runtime memory on x86-64, 119934273f41SH. Peter Anvin 120034273f41SH. Peter Anvinconfig X86_ESPFIX32 120134273f41SH. Peter Anvin def_bool y 120234273f41SH. Peter Anvin depends on X86_16BIT && X86_32 1203506f1d07SSam Ravnborg 1204197725deSH. Peter Anvinconfig X86_ESPFIX64 1205197725deSH. Peter Anvin def_bool y 120634273f41SH. Peter Anvin depends on X86_16BIT && X86_64 1207506f1d07SSam Ravnborg 12081ad83c85SAndy Lutomirskiconfig X86_VSYSCALL_EMULATION 12091ad83c85SAndy Lutomirski bool "Enable vsyscall emulation" if EXPERT 12101ad83c85SAndy Lutomirski default y 12111ad83c85SAndy Lutomirski depends on X86_64 12121ad83c85SAndy Lutomirski ---help--- 12131ad83c85SAndy Lutomirski This enables emulation of the legacy vsyscall page. Disabling 12141ad83c85SAndy Lutomirski it is roughly equivalent to booting with vsyscall=none, except 12151ad83c85SAndy Lutomirski that it will also disable the helpful warning if a program 12161ad83c85SAndy Lutomirski tries to use a vsyscall. With this option set to N, offending 12171ad83c85SAndy Lutomirski programs will just segfault, citing addresses of the form 12181ad83c85SAndy Lutomirski 0xffffffffff600?00. 12191ad83c85SAndy Lutomirski 12201ad83c85SAndy Lutomirski This option is required by many programs built before 2013, and 12211ad83c85SAndy Lutomirski care should be used even with newer programs if set to N. 12221ad83c85SAndy Lutomirski 12231ad83c85SAndy Lutomirski Disabling this option saves about 7K of kernel size and 12241ad83c85SAndy Lutomirski possibly 4K of additional runtime pagetable memory. 12251ad83c85SAndy Lutomirski 1226506f1d07SSam Ravnborgconfig TOSHIBA 1227506f1d07SSam Ravnborg tristate "Toshiba Laptop support" 1228506f1d07SSam Ravnborg depends on X86_32 1229506f1d07SSam Ravnborg ---help--- 1230506f1d07SSam Ravnborg This adds a driver to safely access the System Management Mode of 1231506f1d07SSam Ravnborg the CPU on Toshiba portables with a genuine Toshiba BIOS. It does 1232506f1d07SSam Ravnborg not work on models with a Phoenix BIOS. The System Management Mode 1233506f1d07SSam Ravnborg is used to set the BIOS and power saving options on Toshiba portables. 1234506f1d07SSam Ravnborg 1235506f1d07SSam Ravnborg For information on utilities to make use of this driver see the 1236506f1d07SSam Ravnborg Toshiba Linux utilities web site at: 1237506f1d07SSam Ravnborg <http://www.buzzard.org.uk/toshiba/>. 1238506f1d07SSam Ravnborg 1239506f1d07SSam Ravnborg Say Y if you intend to run this kernel on a Toshiba portable. 1240506f1d07SSam Ravnborg Say N otherwise. 1241506f1d07SSam Ravnborg 1242506f1d07SSam Ravnborgconfig I8K 1243039ae585SPali Rohár tristate "Dell i8k legacy laptop support" 1244949a9d70SJean Delvare select HWMON 1245039ae585SPali Rohár select SENSORS_DELL_SMM 1246506f1d07SSam Ravnborg ---help--- 1247039ae585SPali Rohár This option enables legacy /proc/i8k userspace interface in hwmon 1248039ae585SPali Rohár dell-smm-hwmon driver. Character file /proc/i8k reports bios version, 1249039ae585SPali Rohár temperature and allows controlling fan speeds of Dell laptops via 1250039ae585SPali Rohár System Management Mode. For old Dell laptops (like Dell Inspiron 8000) 1251039ae585SPali Rohár it reports also power and hotkey status. For fan speed control is 1252039ae585SPali Rohár needed userspace package i8kutils. 1253506f1d07SSam Ravnborg 1254039ae585SPali Rohár Say Y if you intend to run this kernel on old Dell laptops or want to 1255039ae585SPali Rohár use userspace package i8kutils. 1256506f1d07SSam Ravnborg Say N otherwise. 1257506f1d07SSam Ravnborg 1258506f1d07SSam Ravnborgconfig X86_REBOOTFIXUPS 12599ba16087SJan Beulich bool "Enable X86 board specific fixups for reboot" 12609ba16087SJan Beulich depends on X86_32 1261506f1d07SSam Ravnborg ---help--- 1262506f1d07SSam Ravnborg This enables chipset and/or board specific fixups to be done 1263506f1d07SSam Ravnborg in order to get reboot to work correctly. This is only needed on 1264506f1d07SSam Ravnborg some combinations of hardware and BIOS. The symptom, for which 1265506f1d07SSam Ravnborg this config is intended, is when reboot ends with a stalled/hung 1266506f1d07SSam Ravnborg system. 1267506f1d07SSam Ravnborg 1268506f1d07SSam Ravnborg Currently, the only fixup is for the Geode machines using 12695e3a77e9SFlorian Fainelli CS5530A and CS5536 chipsets and the RDC R-321x SoC. 1270506f1d07SSam Ravnborg 1271506f1d07SSam Ravnborg Say Y if you want to enable the fixup. Currently, it's safe to 1272506f1d07SSam Ravnborg enable this option even if you don't need it. 1273506f1d07SSam Ravnborg Say N otherwise. 1274506f1d07SSam Ravnborg 1275506f1d07SSam Ravnborgconfig MICROCODE 12769a2bc335SBorislav Petkov bool "CPU microcode loading support" 12779a2bc335SBorislav Petkov default y 127880030e3dSBorislav Petkov depends on CPU_SUP_AMD || CPU_SUP_INTEL 1279506f1d07SSam Ravnborg select FW_LOADER 1280506f1d07SSam Ravnborg ---help--- 1281506f1d07SSam Ravnborg If you say Y here, you will be able to update the microcode on 12825f9c01aaSBorislav Petkov Intel and AMD processors. The Intel support is for the IA32 family, 12835f9c01aaSBorislav Petkov e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The 12845f9c01aaSBorislav Petkov AMD support is for families 0x10 and later. You will obviously need 12855f9c01aaSBorislav Petkov the actual microcode binary data itself which is not shipped with 12865f9c01aaSBorislav Petkov the Linux kernel. 1287506f1d07SSam Ravnborg 12885f9c01aaSBorislav Petkov The preferred method to load microcode from a detached initrd is described 12891897a969SJaak Ristioja in Documentation/x86/microcode.txt. For that you need to enable 12905f9c01aaSBorislav Petkov CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the 12915f9c01aaSBorislav Petkov initrd for microcode blobs. 1292506f1d07SSam Ravnborg 1293c508c46eSBenjamin Gilbert In addition, you can build the microcode into the kernel. For that you 1294c508c46eSBenjamin Gilbert need to add the vendor-supplied microcode to the CONFIG_EXTRA_FIRMWARE 1295c508c46eSBenjamin Gilbert config option. 1296506f1d07SSam Ravnborg 12978d86f390SPeter Orubaconfig MICROCODE_INTEL 1298e43f6e67SBorislav Petkov bool "Intel microcode loading support" 12998d86f390SPeter Oruba depends on MICROCODE 13008d86f390SPeter Oruba default MICROCODE 13018d86f390SPeter Oruba select FW_LOADER 13028f9ca475SIngo Molnar ---help--- 13038d86f390SPeter Oruba This options enables microcode patch loading support for Intel 13048d86f390SPeter Oruba processors. 13058d86f390SPeter Oruba 1306b8989db9SAlan For the current Intel microcode data package go to 1307b8989db9SAlan <https://downloadcenter.intel.com> and search for 1308b8989db9SAlan 'Linux Processor Microcode Data File'. 13098d86f390SPeter Oruba 131080cc9f10SPeter Orubaconfig MICROCODE_AMD 1311e43f6e67SBorislav Petkov bool "AMD microcode loading support" 131280cc9f10SPeter Oruba depends on MICROCODE 131380cc9f10SPeter Oruba select FW_LOADER 13148f9ca475SIngo Molnar ---help--- 131580cc9f10SPeter Oruba If you select this option, microcode patch loading support for AMD 131680cc9f10SPeter Oruba processors will be enabled. 131780cc9f10SPeter Oruba 1318506f1d07SSam Ravnborgconfig MICROCODE_OLD_INTERFACE 1319c02f48e0SBorislav Petkov bool "Ancient loading interface (DEPRECATED)" 1320c02f48e0SBorislav Petkov default n 1321506f1d07SSam Ravnborg depends on MICROCODE 1322c02f48e0SBorislav Petkov ---help--- 1323c02f48e0SBorislav Petkov DO NOT USE THIS! This is the ancient /dev/cpu/microcode interface 1324c02f48e0SBorislav Petkov which was used by userspace tools like iucode_tool and microcode.ctl. 1325c02f48e0SBorislav Petkov It is inadequate because it runs too late to be able to properly 1326c02f48e0SBorislav Petkov load microcode on a machine and it needs special tools. Instead, you 1327c02f48e0SBorislav Petkov should've switched to the early loading method with the initrd or 1328c02f48e0SBorislav Petkov builtin microcode by now: Documentation/x86/microcode.txt 1329506f1d07SSam Ravnborg 1330506f1d07SSam Ravnborgconfig X86_MSR 1331506f1d07SSam Ravnborg tristate "/dev/cpu/*/msr - Model-specific register support" 13328f9ca475SIngo Molnar ---help--- 1333506f1d07SSam Ravnborg This device gives privileged processes access to the x86 1334506f1d07SSam Ravnborg Model-Specific Registers (MSRs). It is a character device with 1335506f1d07SSam Ravnborg major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. 1336506f1d07SSam Ravnborg MSR accesses are directed to a specific CPU on multi-processor 1337506f1d07SSam Ravnborg systems. 1338506f1d07SSam Ravnborg 1339506f1d07SSam Ravnborgconfig X86_CPUID 1340506f1d07SSam Ravnborg tristate "/dev/cpu/*/cpuid - CPU information support" 13418f9ca475SIngo Molnar ---help--- 1342506f1d07SSam Ravnborg This device gives processes access to the x86 CPUID instruction to 1343506f1d07SSam Ravnborg be executed on a specific processor. It is a character device 1344506f1d07SSam Ravnborg with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to 1345506f1d07SSam Ravnborg /dev/cpu/31/cpuid. 1346506f1d07SSam Ravnborg 1347506f1d07SSam Ravnborgchoice 1348506f1d07SSam Ravnborg prompt "High Memory Support" 13496fc108a0SJan Beulich default HIGHMEM4G 1350506f1d07SSam Ravnborg depends on X86_32 1351506f1d07SSam Ravnborg 1352506f1d07SSam Ravnborgconfig NOHIGHMEM 1353506f1d07SSam Ravnborg bool "off" 1354506f1d07SSam Ravnborg ---help--- 1355506f1d07SSam Ravnborg Linux can use up to 64 Gigabytes of physical memory on x86 systems. 1356506f1d07SSam Ravnborg However, the address space of 32-bit x86 processors is only 4 1357506f1d07SSam Ravnborg Gigabytes large. That means that, if you have a large amount of 1358506f1d07SSam Ravnborg physical memory, not all of it can be "permanently mapped" by the 1359506f1d07SSam Ravnborg kernel. The physical memory that's not permanently mapped is called 1360506f1d07SSam Ravnborg "high memory". 1361506f1d07SSam Ravnborg 1362506f1d07SSam Ravnborg If you are compiling a kernel which will never run on a machine with 1363506f1d07SSam Ravnborg more than 1 Gigabyte total physical RAM, answer "off" here (default 1364506f1d07SSam Ravnborg choice and suitable for most users). This will result in a "3GB/1GB" 1365506f1d07SSam Ravnborg split: 3GB are mapped so that each process sees a 3GB virtual memory 1366506f1d07SSam Ravnborg space and the remaining part of the 4GB virtual memory space is used 1367506f1d07SSam Ravnborg by the kernel to permanently map as much physical memory as 1368506f1d07SSam Ravnborg possible. 1369506f1d07SSam Ravnborg 1370506f1d07SSam Ravnborg If the machine has between 1 and 4 Gigabytes physical RAM, then 1371506f1d07SSam Ravnborg answer "4GB" here. 1372506f1d07SSam Ravnborg 1373506f1d07SSam Ravnborg If more than 4 Gigabytes is used then answer "64GB" here. This 1374506f1d07SSam Ravnborg selection turns Intel PAE (Physical Address Extension) mode on. 1375506f1d07SSam Ravnborg PAE implements 3-level paging on IA32 processors. PAE is fully 1376506f1d07SSam Ravnborg supported by Linux, PAE mode is implemented on all recent Intel 1377506f1d07SSam Ravnborg processors (Pentium Pro and better). NOTE: If you say "64GB" here, 1378506f1d07SSam Ravnborg then the kernel will not boot on CPUs that don't support PAE! 1379506f1d07SSam Ravnborg 1380506f1d07SSam Ravnborg The actual amount of total physical memory will either be 1381506f1d07SSam Ravnborg auto detected or can be forced by using a kernel command line option 1382506f1d07SSam Ravnborg such as "mem=256M". (Try "man bootparam" or see the documentation of 1383506f1d07SSam Ravnborg your boot loader (lilo or loadlin) about how to pass options to the 1384506f1d07SSam Ravnborg kernel at boot time.) 1385506f1d07SSam Ravnborg 1386506f1d07SSam Ravnborg If unsure, say "off". 1387506f1d07SSam Ravnborg 1388506f1d07SSam Ravnborgconfig HIGHMEM4G 1389506f1d07SSam Ravnborg bool "4GB" 13908f9ca475SIngo Molnar ---help--- 1391506f1d07SSam Ravnborg Select this if you have a 32-bit processor and between 1 and 4 1392506f1d07SSam Ravnborg gigabytes of physical RAM. 1393506f1d07SSam Ravnborg 1394506f1d07SSam Ravnborgconfig HIGHMEM64G 1395506f1d07SSam Ravnborg bool "64GB" 139669b8d3fcSMatthew Whitehead depends on !M486 && !M586 && !M586TSC && !M586MMX && !MGEODE_LX && !MGEODEGX1 && !MCYRIXIII && !MELAN && !MWINCHIPC6 && !WINCHIP3D && !MK6 1397506f1d07SSam Ravnborg select X86_PAE 13988f9ca475SIngo Molnar ---help--- 1399506f1d07SSam Ravnborg Select this if you have a 32-bit processor and more than 4 1400506f1d07SSam Ravnborg gigabytes of physical RAM. 1401506f1d07SSam Ravnborg 1402506f1d07SSam Ravnborgendchoice 1403506f1d07SSam Ravnborg 1404506f1d07SSam Ravnborgchoice 14056a108a14SDavid Rientjes prompt "Memory split" if EXPERT 1406506f1d07SSam Ravnborg default VMSPLIT_3G 1407506f1d07SSam Ravnborg depends on X86_32 14088f9ca475SIngo Molnar ---help--- 1409506f1d07SSam Ravnborg Select the desired split between kernel and user memory. 1410506f1d07SSam Ravnborg 1411506f1d07SSam Ravnborg If the address range available to the kernel is less than the 1412506f1d07SSam Ravnborg physical memory installed, the remaining memory will be available 1413506f1d07SSam Ravnborg as "high memory". Accessing high memory is a little more costly 1414506f1d07SSam Ravnborg than low memory, as it needs to be mapped into the kernel first. 1415506f1d07SSam Ravnborg Note that increasing the kernel address space limits the range 1416506f1d07SSam Ravnborg available to user programs, making the address space there 1417506f1d07SSam Ravnborg tighter. Selecting anything other than the default 3G/1G split 1418506f1d07SSam Ravnborg will also likely make your kernel incompatible with binary-only 1419506f1d07SSam Ravnborg kernel modules. 1420506f1d07SSam Ravnborg 1421506f1d07SSam Ravnborg If you are not absolutely sure what you are doing, leave this 1422506f1d07SSam Ravnborg option alone! 1423506f1d07SSam Ravnborg 1424506f1d07SSam Ravnborg config VMSPLIT_3G 1425506f1d07SSam Ravnborg bool "3G/1G user/kernel split" 1426506f1d07SSam Ravnborg config VMSPLIT_3G_OPT 1427506f1d07SSam Ravnborg depends on !X86_PAE 1428506f1d07SSam Ravnborg bool "3G/1G user/kernel split (for full 1G low memory)" 1429506f1d07SSam Ravnborg config VMSPLIT_2G 1430506f1d07SSam Ravnborg bool "2G/2G user/kernel split" 1431506f1d07SSam Ravnborg config VMSPLIT_2G_OPT 1432506f1d07SSam Ravnborg depends on !X86_PAE 1433506f1d07SSam Ravnborg bool "2G/2G user/kernel split (for full 2G low memory)" 1434506f1d07SSam Ravnborg config VMSPLIT_1G 1435506f1d07SSam Ravnborg bool "1G/3G user/kernel split" 1436506f1d07SSam Ravnborgendchoice 1437506f1d07SSam Ravnborg 1438506f1d07SSam Ravnborgconfig PAGE_OFFSET 1439506f1d07SSam Ravnborg hex 1440506f1d07SSam Ravnborg default 0xB0000000 if VMSPLIT_3G_OPT 1441506f1d07SSam Ravnborg default 0x80000000 if VMSPLIT_2G 1442506f1d07SSam Ravnborg default 0x78000000 if VMSPLIT_2G_OPT 1443506f1d07SSam Ravnborg default 0x40000000 if VMSPLIT_1G 1444506f1d07SSam Ravnborg default 0xC0000000 1445506f1d07SSam Ravnborg depends on X86_32 1446506f1d07SSam Ravnborg 1447506f1d07SSam Ravnborgconfig HIGHMEM 14483c2362e6SHarvey Harrison def_bool y 1449506f1d07SSam Ravnborg depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) 1450506f1d07SSam Ravnborg 1451506f1d07SSam Ravnborgconfig X86_PAE 14529ba16087SJan Beulich bool "PAE (Physical Address Extension) Support" 1453506f1d07SSam Ravnborg depends on X86_32 && !HIGHMEM4G 1454d4a451d5SChristoph Hellwig select PHYS_ADDR_T_64BIT 14559d99c712SChristian Melki select SWIOTLB 14568f9ca475SIngo Molnar ---help--- 1457506f1d07SSam Ravnborg PAE is required for NX support, and furthermore enables 1458506f1d07SSam Ravnborg larger swapspace support for non-overcommit purposes. It 1459506f1d07SSam Ravnborg has the cost of more pagetable lookup overhead, and also 1460506f1d07SSam Ravnborg consumes more pagetable space per process. 1461506f1d07SSam Ravnborg 146277ef56e4SKirill A. Shutemovconfig X86_5LEVEL 146377ef56e4SKirill A. Shutemov bool "Enable 5-level page tables support" 1464eedb92abSKirill A. Shutemov select DYNAMIC_MEMORY_LAYOUT 1465162434e7SKirill A. Shutemov select SPARSEMEM_VMEMMAP 146677ef56e4SKirill A. Shutemov depends on X86_64 146777ef56e4SKirill A. Shutemov ---help--- 146877ef56e4SKirill A. Shutemov 5-level paging enables access to larger address space: 146977ef56e4SKirill A. Shutemov upto 128 PiB of virtual address space and 4 PiB of 147077ef56e4SKirill A. Shutemov physical address space. 147177ef56e4SKirill A. Shutemov 147277ef56e4SKirill A. Shutemov It will be supported by future Intel CPUs. 147377ef56e4SKirill A. Shutemov 14746657fca0SKirill A. Shutemov A kernel with the option enabled can be booted on machines that 14756657fca0SKirill A. Shutemov support 4- or 5-level paging. 147677ef56e4SKirill A. Shutemov 147777ef56e4SKirill A. Shutemov See Documentation/x86/x86_64/5level-paging.txt for more 147877ef56e4SKirill A. Shutemov information. 147977ef56e4SKirill A. Shutemov 148077ef56e4SKirill A. Shutemov Say N if unsure. 148177ef56e4SKirill A. Shutemov 148210971ab2SIngo Molnarconfig X86_DIRECT_GBPAGES 1483e5008abeSLuis R. Rodriguez def_bool y 14844675ff05SLevin, Alexander (Sasha Levin) depends on X86_64 && !DEBUG_PAGEALLOC 14858f9ca475SIngo Molnar ---help--- 148610971ab2SIngo Molnar Certain kernel features effectively disable kernel 148710971ab2SIngo Molnar linear 1 GB mappings (even if the CPU otherwise 148810971ab2SIngo Molnar supports them), so don't confuse the user by printing 148910971ab2SIngo Molnar that we have them enabled. 14909e899816SNick Piggin 14915c280cf6SThomas Gleixnerconfig X86_CPA_STATISTICS 14925c280cf6SThomas Gleixner bool "Enable statistic for Change Page Attribute" 14935c280cf6SThomas Gleixner depends on DEBUG_FS 14945c280cf6SThomas Gleixner ---help--- 14955c280cf6SThomas Gleixner Expose statistics about the Change Page Attribute mechanims, which 1496a943245aSColin Ian King helps to determine the effectiveness of preserving large and huge 14975c280cf6SThomas Gleixner page mappings when mapping protections are changed. 14985c280cf6SThomas Gleixner 14997744ccdbSTom Lendackyconfig ARCH_HAS_MEM_ENCRYPT 15007744ccdbSTom Lendacky def_bool y 15017744ccdbSTom Lendacky 15027744ccdbSTom Lendackyconfig AMD_MEM_ENCRYPT 15037744ccdbSTom Lendacky bool "AMD Secure Memory Encryption (SME) support" 15047744ccdbSTom Lendacky depends on X86_64 && CPU_SUP_AMD 150594d49eb3SKirill A. Shutemov select DYNAMIC_PHYSICAL_MASK 1506ce9084baSArd Biesheuvel select ARCH_USE_MEMREMAP_PROT 15077744ccdbSTom Lendacky ---help--- 15087744ccdbSTom Lendacky Say yes to enable support for the encryption of system memory. 15097744ccdbSTom Lendacky This requires an AMD processor that supports Secure Memory 15107744ccdbSTom Lendacky Encryption (SME). 15117744ccdbSTom Lendacky 15127744ccdbSTom Lendackyconfig AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT 15137744ccdbSTom Lendacky bool "Activate AMD Secure Memory Encryption (SME) by default" 15147744ccdbSTom Lendacky default y 15157744ccdbSTom Lendacky depends on AMD_MEM_ENCRYPT 15167744ccdbSTom Lendacky ---help--- 15177744ccdbSTom Lendacky Say yes to have system memory encrypted by default if running on 15187744ccdbSTom Lendacky an AMD processor that supports Secure Memory Encryption (SME). 15197744ccdbSTom Lendacky 15207744ccdbSTom Lendacky If set to Y, then the encryption of system memory can be 15217744ccdbSTom Lendacky deactivated with the mem_encrypt=off command line option. 15227744ccdbSTom Lendacky 15237744ccdbSTom Lendacky If set to N, then the encryption of system memory can be 15247744ccdbSTom Lendacky activated with the mem_encrypt=on command line option. 15257744ccdbSTom Lendacky 1526506f1d07SSam Ravnborg# Common NUMA Features 1527506f1d07SSam Ravnborgconfig NUMA 1528fd51b2d7SKOSAKI Motohiro bool "Numa Memory Allocation and Scheduler Support" 1529506f1d07SSam Ravnborg depends on SMP 1530b5660ba7SH. Peter Anvin depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP) 1531b5660ba7SH. Peter Anvin default y if X86_BIGSMP 15328f9ca475SIngo Molnar ---help--- 1533506f1d07SSam Ravnborg Enable NUMA (Non Uniform Memory Access) support. 1534fd51b2d7SKOSAKI Motohiro 1535506f1d07SSam Ravnborg The kernel will try to allocate memory used by a CPU on the 1536506f1d07SSam Ravnborg local memory controller of the CPU and add some more 1537506f1d07SSam Ravnborg NUMA awareness to the kernel. 1538506f1d07SSam Ravnborg 1539c280ea5eSIngo Molnar For 64-bit this is recommended if the system is Intel Core i7 1540fd51b2d7SKOSAKI Motohiro (or later), AMD Opteron, or EM64T NUMA. 1541fd51b2d7SKOSAKI Motohiro 1542b5660ba7SH. Peter Anvin For 32-bit this is only needed if you boot a 32-bit 15437cf6c945SDavid Rientjes kernel on a 64-bit NUMA platform. 1544fd51b2d7SKOSAKI Motohiro 1545fd51b2d7SKOSAKI Motohiro Otherwise, you should say N. 1546506f1d07SSam Ravnborg 1547eec1d4faSHans Rosenfeldconfig AMD_NUMA 15483c2362e6SHarvey Harrison def_bool y 15493c2362e6SHarvey Harrison prompt "Old style AMD Opteron NUMA detection" 15505da0ef9aSTejun Heo depends on X86_64 && NUMA && PCI 15518f9ca475SIngo Molnar ---help--- 1552eec1d4faSHans Rosenfeld Enable AMD NUMA node topology detection. You should say Y here if 1553eec1d4faSHans Rosenfeld you have a multi processor AMD system. This uses an old method to 1554eec1d4faSHans Rosenfeld read the NUMA configuration directly from the builtin Northbridge 1555eec1d4faSHans Rosenfeld of Opteron. It is recommended to use X86_64_ACPI_NUMA instead, 1556eec1d4faSHans Rosenfeld which also takes priority if both are compiled in. 1557506f1d07SSam Ravnborg 1558506f1d07SSam Ravnborgconfig X86_64_ACPI_NUMA 15593c2362e6SHarvey Harrison def_bool y 15603c2362e6SHarvey Harrison prompt "ACPI NUMA detection" 1561506f1d07SSam Ravnborg depends on X86_64 && NUMA && ACPI && PCI 1562506f1d07SSam Ravnborg select ACPI_NUMA 15638f9ca475SIngo Molnar ---help--- 1564506f1d07SSam Ravnborg Enable ACPI SRAT based node topology detection. 1565506f1d07SSam Ravnborg 15666ec6e0d9SSuresh Siddha# Some NUMA nodes have memory ranges that span 15676ec6e0d9SSuresh Siddha# other nodes. Even though a pfn is valid and 15686ec6e0d9SSuresh Siddha# between a node's start and end pfns, it may not 15696ec6e0d9SSuresh Siddha# reside on that node. See memmap_init_zone() 15706ec6e0d9SSuresh Siddha# for details. 15716ec6e0d9SSuresh Siddhaconfig NODES_SPAN_OTHER_NODES 15726ec6e0d9SSuresh Siddha def_bool y 15736ec6e0d9SSuresh Siddha depends on X86_64_ACPI_NUMA 15746ec6e0d9SSuresh Siddha 1575506f1d07SSam Ravnborgconfig NUMA_EMU 1576506f1d07SSam Ravnborg bool "NUMA emulation" 15771b7e03efSTejun Heo depends on NUMA 15788f9ca475SIngo Molnar ---help--- 1579506f1d07SSam Ravnborg Enable NUMA emulation. A flat machine will be split 1580506f1d07SSam Ravnborg into virtual nodes when booted with "numa=fake=N", where N is the 1581506f1d07SSam Ravnborg number of nodes. This is only useful for debugging. 1582506f1d07SSam Ravnborg 1583506f1d07SSam Ravnborgconfig NODES_SHIFT 1584d25e26b6SLinus Torvalds int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP 158551591e31SDavid Rientjes range 1 10 158651591e31SDavid Rientjes default "10" if MAXSMP 1587506f1d07SSam Ravnborg default "6" if X86_64 1588506f1d07SSam Ravnborg default "3" 1589506f1d07SSam Ravnborg depends on NEED_MULTIPLE_NODES 15908f9ca475SIngo Molnar ---help--- 15911184dc2fSMike Travis Specify the maximum number of NUMA Nodes available on the target 1592692105b8SMatt LaPlante system. Increases memory reserved to accommodate various tables. 1593506f1d07SSam Ravnborg 1594506f1d07SSam Ravnborgconfig ARCH_HAVE_MEMORY_PRESENT 15953c2362e6SHarvey Harrison def_bool y 1596506f1d07SSam Ravnborg depends on X86_32 && DISCONTIGMEM 1597506f1d07SSam Ravnborg 1598506f1d07SSam Ravnborgconfig ARCH_FLATMEM_ENABLE 1599506f1d07SSam Ravnborg def_bool y 16003b16651fSTejun Heo depends on X86_32 && !NUMA 1601506f1d07SSam Ravnborg 1602506f1d07SSam Ravnborgconfig ARCH_DISCONTIGMEM_ENABLE 16032792107dSMike Rapoport def_bool n 1604b263295dSChristoph Lameter depends on NUMA && X86_32 16052792107dSMike Rapoport depends on BROKEN 1606b263295dSChristoph Lameter 1607506f1d07SSam Ravnborgconfig ARCH_SPARSEMEM_ENABLE 1608506f1d07SSam Ravnborg def_bool y 16096ea30386SKees Cook depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD 1610506f1d07SSam Ravnborg select SPARSEMEM_STATIC if X86_32 1611506f1d07SSam Ravnborg select SPARSEMEM_VMEMMAP_ENABLE if X86_64 1612506f1d07SSam Ravnborg 16133b16651fSTejun Heoconfig ARCH_SPARSEMEM_DEFAULT 16146ad57f7fSMike Rapoport def_bool X86_64 || (NUMA && X86_32) 16153b16651fSTejun Heo 1616506f1d07SSam Ravnborgconfig ARCH_SELECT_MEMORY_MODEL 1617506f1d07SSam Ravnborg def_bool y 1618b263295dSChristoph Lameter depends on ARCH_SPARSEMEM_ENABLE 1619506f1d07SSam Ravnborg 1620506f1d07SSam Ravnborgconfig ARCH_MEMORY_PROBE 1621a0842b70SToshi Kani bool "Enable sysfs memory/probe interface" 16223120e25eSJan Beulich depends on X86_64 && MEMORY_HOTPLUG 1623a0842b70SToshi Kani help 1624a0842b70SToshi Kani This option enables a sysfs memory/probe interface for testing. 1625a0842b70SToshi Kani See Documentation/memory-hotplug.txt for more information. 1626a0842b70SToshi Kani If you are unsure how to answer this question, answer N. 1627506f1d07SSam Ravnborg 16283b16651fSTejun Heoconfig ARCH_PROC_KCORE_TEXT 16293b16651fSTejun Heo def_bool y 16303b16651fSTejun Heo depends on X86_64 && PROC_KCORE 16313b16651fSTejun Heo 1632a29815a3SAvi Kivityconfig ILLEGAL_POINTER_VALUE 1633a29815a3SAvi Kivity hex 1634a29815a3SAvi Kivity default 0 if X86_32 1635a29815a3SAvi Kivity default 0xdead000000000000 if X86_64 1636a29815a3SAvi Kivity 16377a67832cSDan Williamsconfig X86_PMEM_LEGACY_DEVICE 16387a67832cSDan Williams bool 16397a67832cSDan Williams 1640ec776ef6SChristoph Hellwigconfig X86_PMEM_LEGACY 16417a67832cSDan Williams tristate "Support non-standard NVDIMMs and ADR protected memory" 16429f53f9faSDan Williams depends on PHYS_ADDR_T_64BIT 16439f53f9faSDan Williams depends on BLK_DEV 16447a67832cSDan Williams select X86_PMEM_LEGACY_DEVICE 16459f53f9faSDan Williams select LIBNVDIMM 1646ec776ef6SChristoph Hellwig help 1647ec776ef6SChristoph Hellwig Treat memory marked using the non-standard e820 type of 12 as used 1648ec776ef6SChristoph Hellwig by the Intel Sandy Bridge-EP reference BIOS as protected memory. 1649ec776ef6SChristoph Hellwig The kernel will offer these regions to the 'pmem' driver so 1650ec776ef6SChristoph Hellwig they can be used for persistent storage. 1651ec776ef6SChristoph Hellwig 1652ec776ef6SChristoph Hellwig Say Y if unsure. 1653ec776ef6SChristoph Hellwig 1654506f1d07SSam Ravnborgconfig HIGHPTE 1655506f1d07SSam Ravnborg bool "Allocate 3rd-level pagetables from highmem" 16566fc108a0SJan Beulich depends on HIGHMEM 16578f9ca475SIngo Molnar ---help--- 1658506f1d07SSam Ravnborg The VM uses one page table entry for each page of physical memory. 1659506f1d07SSam Ravnborg For systems with a lot of RAM, this can be wasteful of precious 1660506f1d07SSam Ravnborg low memory. Setting this option will put user-space page table 1661506f1d07SSam Ravnborg entries in high memory. 1662506f1d07SSam Ravnborg 16639f077871SJeremy Fitzhardingeconfig X86_CHECK_BIOS_CORRUPTION 16649f077871SJeremy Fitzhardinge bool "Check for low memory corruption" 16658f9ca475SIngo Molnar ---help--- 16669f077871SJeremy Fitzhardinge Periodically check for memory corruption in low memory, which 16679f077871SJeremy Fitzhardinge is suspected to be caused by BIOS. Even when enabled in the 16689f077871SJeremy Fitzhardinge configuration, it is disabled at runtime. Enable it by 16699f077871SJeremy Fitzhardinge setting "memory_corruption_check=1" on the kernel command 16709f077871SJeremy Fitzhardinge line. By default it scans the low 64k of memory every 60 16719f077871SJeremy Fitzhardinge seconds; see the memory_corruption_check_size and 16729f077871SJeremy Fitzhardinge memory_corruption_check_period parameters in 16738c27ceffSMauro Carvalho Chehab Documentation/admin-guide/kernel-parameters.rst to adjust this. 16749f077871SJeremy Fitzhardinge 16759f077871SJeremy Fitzhardinge When enabled with the default parameters, this option has 16769f077871SJeremy Fitzhardinge almost no overhead, as it reserves a relatively small amount 16779f077871SJeremy Fitzhardinge of memory and scans it infrequently. It both detects corruption 16789f077871SJeremy Fitzhardinge and prevents it from affecting the running system. 16799f077871SJeremy Fitzhardinge 16809f077871SJeremy Fitzhardinge It is, however, intended as a diagnostic tool; if repeatable 16819f077871SJeremy Fitzhardinge BIOS-originated corruption always affects the same memory, 16829f077871SJeremy Fitzhardinge you can use memmap= to prevent the kernel from using that 16839f077871SJeremy Fitzhardinge memory. 16849f077871SJeremy Fitzhardinge 1685c885df50SJeremy Fitzhardingeconfig X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK 1686c885df50SJeremy Fitzhardinge bool "Set the default setting of memory_corruption_check" 1687c885df50SJeremy Fitzhardinge depends on X86_CHECK_BIOS_CORRUPTION 1688c885df50SJeremy Fitzhardinge default y 16898f9ca475SIngo Molnar ---help--- 1690c885df50SJeremy Fitzhardinge Set whether the default state of memory_corruption_check is 1691c885df50SJeremy Fitzhardinge on or off. 1692c885df50SJeremy Fitzhardinge 16939ea77bdbSH. Peter Anvinconfig X86_RESERVE_LOW 1694d0cd7425SH. Peter Anvin int "Amount of low memory, in kilobytes, to reserve for the BIOS" 1695d0cd7425SH. Peter Anvin default 64 1696d0cd7425SH. Peter Anvin range 4 640 16978f9ca475SIngo Molnar ---help--- 1698d0cd7425SH. Peter Anvin Specify the amount of low memory to reserve for the BIOS. 1699fc381519SIngo Molnar 1700d0cd7425SH. Peter Anvin The first page contains BIOS data structures that the kernel 1701d0cd7425SH. Peter Anvin must not use, so that page must always be reserved. 1702fc381519SIngo Molnar 1703d0cd7425SH. Peter Anvin By default we reserve the first 64K of physical RAM, as a 1704d0cd7425SH. Peter Anvin number of BIOSes are known to corrupt that memory range 1705d0cd7425SH. Peter Anvin during events such as suspend/resume or monitor cable 1706d0cd7425SH. Peter Anvin insertion, so it must not be used by the kernel. 1707fc381519SIngo Molnar 1708d0cd7425SH. Peter Anvin You can set this to 4 if you are absolutely sure that you 1709d0cd7425SH. Peter Anvin trust the BIOS to get all its memory reservations and usages 1710d0cd7425SH. Peter Anvin right. If you know your BIOS have problems beyond the 1711d0cd7425SH. Peter Anvin default 64K area, you can set this to 640 to avoid using the 1712d0cd7425SH. Peter Anvin entire low memory range. 1713d0cd7425SH. Peter Anvin 1714d0cd7425SH. Peter Anvin If you have doubts about the BIOS (e.g. suspend/resume does 1715d0cd7425SH. Peter Anvin not work or there's kernel crashes after certain hardware 1716d0cd7425SH. Peter Anvin hotplug events) then you might want to enable 1717d0cd7425SH. Peter Anvin X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check 1718d0cd7425SH. Peter Anvin typical corruption patterns. 1719d0cd7425SH. Peter Anvin 1720d0cd7425SH. Peter Anvin Leave this to the default value of 64 if you are unsure. 1721fc381519SIngo Molnar 1722506f1d07SSam Ravnborgconfig MATH_EMULATION 1723506f1d07SSam Ravnborg bool 1724a5b9e5a2SAndy Lutomirski depends on MODIFY_LDT_SYSCALL 1725506f1d07SSam Ravnborg prompt "Math emulation" if X86_32 1726506f1d07SSam Ravnborg ---help--- 1727506f1d07SSam Ravnborg Linux can emulate a math coprocessor (used for floating point 1728506f1d07SSam Ravnborg operations) if you don't have one. 486DX and Pentium processors have 1729506f1d07SSam Ravnborg a math coprocessor built in, 486SX and 386 do not, unless you added 1730506f1d07SSam Ravnborg a 487DX or 387, respectively. (The messages during boot time can 1731506f1d07SSam Ravnborg give you some hints here ["man dmesg"].) Everyone needs either a 1732506f1d07SSam Ravnborg coprocessor or this emulation. 1733506f1d07SSam Ravnborg 1734506f1d07SSam Ravnborg If you don't have a math coprocessor, you need to say Y here; if you 1735506f1d07SSam Ravnborg say Y here even though you have a coprocessor, the coprocessor will 1736506f1d07SSam Ravnborg be used nevertheless. (This behavior can be changed with the kernel 1737506f1d07SSam Ravnborg command line option "no387", which comes handy if your coprocessor 1738506f1d07SSam Ravnborg is broken. Try "man bootparam" or see the documentation of your boot 1739506f1d07SSam Ravnborg loader (lilo or loadlin) about how to pass options to the kernel at 1740506f1d07SSam Ravnborg boot time.) This means that it is a good idea to say Y here if you 1741506f1d07SSam Ravnborg intend to use this kernel on different machines. 1742506f1d07SSam Ravnborg 1743506f1d07SSam Ravnborg More information about the internals of the Linux math coprocessor 1744506f1d07SSam Ravnborg emulation can be found in <file:arch/x86/math-emu/README>. 1745506f1d07SSam Ravnborg 1746506f1d07SSam Ravnborg If you are not sure, say Y; apart from resulting in a 66 KB bigger 1747506f1d07SSam Ravnborg kernel, it won't hurt. 1748506f1d07SSam Ravnborg 1749506f1d07SSam Ravnborgconfig MTRR 17506fc108a0SJan Beulich def_bool y 17516a108a14SDavid Rientjes prompt "MTRR (Memory Type Range Register) support" if EXPERT 1752506f1d07SSam Ravnborg ---help--- 1753506f1d07SSam Ravnborg On Intel P6 family processors (Pentium Pro, Pentium II and later) 1754506f1d07SSam Ravnborg the Memory Type Range Registers (MTRRs) may be used to control 1755506f1d07SSam Ravnborg processor access to memory ranges. This is most useful if you have 1756506f1d07SSam Ravnborg a video (VGA) card on a PCI or AGP bus. Enabling write-combining 1757506f1d07SSam Ravnborg allows bus write transfers to be combined into a larger transfer 1758506f1d07SSam Ravnborg before bursting over the PCI/AGP bus. This can increase performance 1759506f1d07SSam Ravnborg of image write operations 2.5 times or more. Saying Y here creates a 1760506f1d07SSam Ravnborg /proc/mtrr file which may be used to manipulate your processor's 1761506f1d07SSam Ravnborg MTRRs. Typically the X server should use this. 1762506f1d07SSam Ravnborg 1763506f1d07SSam Ravnborg This code has a reasonably generic interface so that similar 1764506f1d07SSam Ravnborg control registers on other processors can be easily supported 1765506f1d07SSam Ravnborg as well: 1766506f1d07SSam Ravnborg 1767506f1d07SSam Ravnborg The Cyrix 6x86, 6x86MX and M II processors have Address Range 1768506f1d07SSam Ravnborg Registers (ARRs) which provide a similar functionality to MTRRs. For 1769506f1d07SSam Ravnborg these, the ARRs are used to emulate the MTRRs. 1770506f1d07SSam Ravnborg The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 1771506f1d07SSam Ravnborg MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 1772506f1d07SSam Ravnborg write-combining. All of these processors are supported by this code 1773506f1d07SSam Ravnborg and it makes sense to say Y here if you have one of them. 1774506f1d07SSam Ravnborg 1775506f1d07SSam Ravnborg Saying Y here also fixes a problem with buggy SMP BIOSes which only 1776506f1d07SSam Ravnborg set the MTRRs for the boot CPU and not for the secondary CPUs. This 1777506f1d07SSam Ravnborg can lead to all sorts of problems, so it's good to say Y here. 1778506f1d07SSam Ravnborg 1779506f1d07SSam Ravnborg You can safely say Y even if your machine doesn't have MTRRs, you'll 1780506f1d07SSam Ravnborg just add about 9 KB to your kernel. 1781506f1d07SSam Ravnborg 17827225e751SRandy Dunlap See <file:Documentation/x86/mtrr.txt> for more information. 1783506f1d07SSam Ravnborg 178495ffa243SYinghai Luconfig MTRR_SANITIZER 17852ffb3501SYinghai Lu def_bool y 178695ffa243SYinghai Lu prompt "MTRR cleanup support" 178795ffa243SYinghai Lu depends on MTRR 17888f9ca475SIngo Molnar ---help--- 1789aba3728cSThomas Gleixner Convert MTRR layout from continuous to discrete, so X drivers can 1790aba3728cSThomas Gleixner add writeback entries. 179195ffa243SYinghai Lu 1792aba3728cSThomas Gleixner Can be disabled with disable_mtrr_cleanup on the kernel command line. 1793692105b8SMatt LaPlante The largest mtrr entry size for a continuous block can be set with 1794aba3728cSThomas Gleixner mtrr_chunk_size. 179595ffa243SYinghai Lu 17962ffb3501SYinghai Lu If unsure, say Y. 179795ffa243SYinghai Lu 179895ffa243SYinghai Luconfig MTRR_SANITIZER_ENABLE_DEFAULT 1799f5098d62SYinghai Lu int "MTRR cleanup enable value (0-1)" 1800f5098d62SYinghai Lu range 0 1 1801f5098d62SYinghai Lu default "0" 180295ffa243SYinghai Lu depends on MTRR_SANITIZER 18038f9ca475SIngo Molnar ---help--- 1804f5098d62SYinghai Lu Enable mtrr cleanup default value 180595ffa243SYinghai Lu 180612031a62SYinghai Luconfig MTRR_SANITIZER_SPARE_REG_NR_DEFAULT 180712031a62SYinghai Lu int "MTRR cleanup spare reg num (0-7)" 180812031a62SYinghai Lu range 0 7 180912031a62SYinghai Lu default "1" 181012031a62SYinghai Lu depends on MTRR_SANITIZER 18118f9ca475SIngo Molnar ---help--- 181212031a62SYinghai Lu mtrr cleanup spare entries default, it can be changed via 1813aba3728cSThomas Gleixner mtrr_spare_reg_nr=N on the kernel command line. 181412031a62SYinghai Lu 18152e5d9c85Svenkatesh.pallipadi@intel.comconfig X86_PAT 18166fc108a0SJan Beulich def_bool y 18176a108a14SDavid Rientjes prompt "x86 PAT support" if EXPERT 18182a8a2719SIngo Molnar depends on MTRR 18198f9ca475SIngo Molnar ---help--- 18202e5d9c85Svenkatesh.pallipadi@intel.com Use PAT attributes to setup page level cache control. 1821042b78e4SVenki Pallipadi 18222e5d9c85Svenkatesh.pallipadi@intel.com PATs are the modern equivalents of MTRRs and are much more 18232e5d9c85Svenkatesh.pallipadi@intel.com flexible than MTRRs. 18242e5d9c85Svenkatesh.pallipadi@intel.com 18252e5d9c85Svenkatesh.pallipadi@intel.com Say N here if you see bootup problems (boot crash, boot hang, 1826042b78e4SVenki Pallipadi spontaneous reboots) or a non-working video driver. 18272e5d9c85Svenkatesh.pallipadi@intel.com 18282e5d9c85Svenkatesh.pallipadi@intel.com If unsure, say Y. 18292e5d9c85Svenkatesh.pallipadi@intel.com 183046cf98cdSVenkatesh Pallipadiconfig ARCH_USES_PG_UNCACHED 183146cf98cdSVenkatesh Pallipadi def_bool y 183246cf98cdSVenkatesh Pallipadi depends on X86_PAT 183346cf98cdSVenkatesh Pallipadi 1834628c6246SH. Peter Anvinconfig ARCH_RANDOM 1835628c6246SH. Peter Anvin def_bool y 1836628c6246SH. Peter Anvin prompt "x86 architectural random number generator" if EXPERT 1837628c6246SH. Peter Anvin ---help--- 1838628c6246SH. Peter Anvin Enable the x86 architectural RDRAND instruction 1839628c6246SH. Peter Anvin (Intel Bull Mountain technology) to generate random numbers. 1840628c6246SH. Peter Anvin If supported, this is a high bandwidth, cryptographically 1841628c6246SH. Peter Anvin secure hardware random number generator. 1842628c6246SH. Peter Anvin 184351ae4a2dSH. Peter Anvinconfig X86_SMAP 184451ae4a2dSH. Peter Anvin def_bool y 184551ae4a2dSH. Peter Anvin prompt "Supervisor Mode Access Prevention" if EXPERT 184651ae4a2dSH. Peter Anvin ---help--- 184751ae4a2dSH. Peter Anvin Supervisor Mode Access Prevention (SMAP) is a security 184851ae4a2dSH. Peter Anvin feature in newer Intel processors. There is a small 184951ae4a2dSH. Peter Anvin performance cost if this enabled and turned on; there is 185051ae4a2dSH. Peter Anvin also a small increase in the kernel size if this is enabled. 185151ae4a2dSH. Peter Anvin 185251ae4a2dSH. Peter Anvin If unsure, say Y. 185351ae4a2dSH. Peter Anvin 1854aa35f896SRicardo Nericonfig X86_INTEL_UMIP 1855796ebc81SRicardo Neri def_bool y 1856aa35f896SRicardo Neri depends on CPU_SUP_INTEL 1857aa35f896SRicardo Neri prompt "Intel User Mode Instruction Prevention" if EXPERT 1858aa35f896SRicardo Neri ---help--- 1859aa35f896SRicardo Neri The User Mode Instruction Prevention (UMIP) is a security 1860aa35f896SRicardo Neri feature in newer Intel processors. If enabled, a general 1861796ebc81SRicardo Neri protection fault is issued if the SGDT, SLDT, SIDT, SMSW 1862796ebc81SRicardo Neri or STR instructions are executed in user mode. These instructions 1863796ebc81SRicardo Neri unnecessarily expose information about the hardware state. 1864796ebc81SRicardo Neri 1865796ebc81SRicardo Neri The vast majority of applications do not use these instructions. 1866796ebc81SRicardo Neri For the very few that do, software emulation is provided in 1867796ebc81SRicardo Neri specific cases in protected and virtual-8086 modes. Emulated 1868796ebc81SRicardo Neri results are dummy. 1869aa35f896SRicardo Neri 187072e9b5feSDave Hansenconfig X86_INTEL_MPX 187172e9b5feSDave Hansen prompt "Intel MPX (Memory Protection Extensions)" 187272e9b5feSDave Hansen def_bool n 1873df3735c5SRik van Riel # Note: only available in 64-bit mode due to VMA flags shortage 1874df3735c5SRik van Riel depends on CPU_SUP_INTEL && X86_64 1875df3735c5SRik van Riel select ARCH_USES_HIGH_VMA_FLAGS 187672e9b5feSDave Hansen ---help--- 187772e9b5feSDave Hansen MPX provides hardware features that can be used in 187872e9b5feSDave Hansen conjunction with compiler-instrumented code to check 187972e9b5feSDave Hansen memory references. It is designed to detect buffer 188072e9b5feSDave Hansen overflow or underflow bugs. 188172e9b5feSDave Hansen 188272e9b5feSDave Hansen This option enables running applications which are 188372e9b5feSDave Hansen instrumented or otherwise use MPX. It does not use MPX 188472e9b5feSDave Hansen itself inside the kernel or to protect the kernel 188572e9b5feSDave Hansen against bad memory references. 188672e9b5feSDave Hansen 188772e9b5feSDave Hansen Enabling this option will make the kernel larger: 188872e9b5feSDave Hansen ~8k of kernel text and 36 bytes of data on a 64-bit 188972e9b5feSDave Hansen defconfig. It adds a long to the 'mm_struct' which 189072e9b5feSDave Hansen will increase the kernel memory overhead of each 189172e9b5feSDave Hansen process and adds some branches to paths used during 189272e9b5feSDave Hansen exec() and munmap(). 189372e9b5feSDave Hansen 189472e9b5feSDave Hansen For details, see Documentation/x86/intel_mpx.txt 189572e9b5feSDave Hansen 189672e9b5feSDave Hansen If unsure, say N. 189772e9b5feSDave Hansen 189835e97790SDave Hansenconfig X86_INTEL_MEMORY_PROTECTION_KEYS 1899284244a9SDave Hansen prompt "Intel Memory Protection Keys" 190035e97790SDave Hansen def_bool y 1901284244a9SDave Hansen # Note: only available in 64-bit mode 190235e97790SDave Hansen depends on CPU_SUP_INTEL && X86_64 190352c8e601SIngo Molnar select ARCH_USES_HIGH_VMA_FLAGS 190452c8e601SIngo Molnar select ARCH_HAS_PKEYS 1905284244a9SDave Hansen ---help--- 1906284244a9SDave Hansen Memory Protection Keys provides a mechanism for enforcing 1907284244a9SDave Hansen page-based protections, but without requiring modification of the 1908284244a9SDave Hansen page tables when an application changes protection domains. 1909284244a9SDave Hansen 1910284244a9SDave Hansen For details, see Documentation/x86/protection-keys.txt 1911284244a9SDave Hansen 1912284244a9SDave Hansen If unsure, say y. 191335e97790SDave Hansen 1914506f1d07SSam Ravnborgconfig EFI 19159ba16087SJan Beulich bool "EFI runtime service support" 19165b83683fSHuang, Ying depends on ACPI 1917f6ce5002SSergey Vlasov select UCS2_STRING 1918022ee6c5SArd Biesheuvel select EFI_RUNTIME_WRAPPERS 1919506f1d07SSam Ravnborg ---help--- 19208b2cb7a8SHuang, Ying This enables the kernel to use EFI runtime services that are 1921506f1d07SSam Ravnborg available (such as the EFI variable services). 1922506f1d07SSam Ravnborg 19238b2cb7a8SHuang, Ying This option is only useful on systems that have EFI firmware. 19248b2cb7a8SHuang, Ying In addition, you should use the latest ELILO loader available 19258b2cb7a8SHuang, Ying at <http://elilo.sourceforge.net> in order to take advantage 19268b2cb7a8SHuang, Ying of EFI runtime services. However, even with this option, the 19278b2cb7a8SHuang, Ying resultant kernel should continue to boot on existing non-EFI 19288b2cb7a8SHuang, Ying platforms. 1929506f1d07SSam Ravnborg 1930291f3632SMatt Flemingconfig EFI_STUB 1931291f3632SMatt Fleming bool "EFI stub support" 1932b16d8c23SMatt Fleming depends on EFI && !X86_USE_3DNOW 19337b2a583aSMatt Fleming select RELOCATABLE 1934291f3632SMatt Fleming ---help--- 1935291f3632SMatt Fleming This kernel feature allows a bzImage to be loaded directly 1936291f3632SMatt Fleming by EFI firmware without the use of a bootloader. 1937291f3632SMatt Fleming 19384172fe2fSRoy Franz See Documentation/efi-stub.txt for more information. 19390c759662SMatt Fleming 19407d453eeeSMatt Flemingconfig EFI_MIXED 19417d453eeeSMatt Fleming bool "EFI mixed-mode support" 19427d453eeeSMatt Fleming depends on EFI_STUB && X86_64 19437d453eeeSMatt Fleming ---help--- 19447d453eeeSMatt Fleming Enabling this feature allows a 64-bit kernel to be booted 19457d453eeeSMatt Fleming on a 32-bit firmware, provided that your CPU supports 64-bit 19467d453eeeSMatt Fleming mode. 19477d453eeeSMatt Fleming 19487d453eeeSMatt Fleming Note that it is not possible to boot a mixed-mode enabled 19497d453eeeSMatt Fleming kernel via the EFI boot stub - a bootloader that supports 19507d453eeeSMatt Fleming the EFI handover protocol must be used. 19517d453eeeSMatt Fleming 19527d453eeeSMatt Fleming If unsure, say N. 19537d453eeeSMatt Fleming 1954506f1d07SSam Ravnborgconfig SECCOMP 19553c2362e6SHarvey Harrison def_bool y 19563c2362e6SHarvey Harrison prompt "Enable seccomp to safely compute untrusted bytecode" 19578f9ca475SIngo Molnar ---help--- 1958506f1d07SSam Ravnborg This kernel feature is useful for number crunching applications 1959506f1d07SSam Ravnborg that may need to compute untrusted bytecode during their 1960506f1d07SSam Ravnborg execution. By using pipes or other transports made available to 1961506f1d07SSam Ravnborg the process as file descriptors supporting the read/write 1962506f1d07SSam Ravnborg syscalls, it's possible to isolate those applications in 1963506f1d07SSam Ravnborg their own address space using seccomp. Once seccomp is 19649c0bbee8SAlexey Dobriyan enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 1965506f1d07SSam Ravnborg and the task is only allowed to execute a few safe syscalls 1966506f1d07SSam Ravnborg defined by each seccomp mode. 1967506f1d07SSam Ravnborg 1968506f1d07SSam Ravnborg If unsure, say Y. Only embedded should say N here. 1969506f1d07SSam Ravnborg 19708636a1f9SMasahiro Yamadasource "kernel/Kconfig.hz" 1971506f1d07SSam Ravnborg 1972506f1d07SSam Ravnborgconfig KEXEC 1973506f1d07SSam Ravnborg bool "kexec system call" 19742965faa5SDave Young select KEXEC_CORE 19758f9ca475SIngo Molnar ---help--- 1976506f1d07SSam Ravnborg kexec is a system call that implements the ability to shutdown your 1977506f1d07SSam Ravnborg current kernel, and to start another kernel. It is like a reboot 1978506f1d07SSam Ravnborg but it is independent of the system firmware. And like a reboot 1979506f1d07SSam Ravnborg you can start any kernel with it, not just Linux. 1980506f1d07SSam Ravnborg 1981506f1d07SSam Ravnborg The name comes from the similarity to the exec system call. 1982506f1d07SSam Ravnborg 1983506f1d07SSam Ravnborg It is an ongoing process to be certain the hardware in a machine 1984506f1d07SSam Ravnborg is properly shutdown, so do not be surprised if this code does not 1985bf220695SGeert Uytterhoeven initially work for you. As of this writing the exact hardware 1986bf220695SGeert Uytterhoeven interface is strongly in flux, so no good recommendation can be 1987bf220695SGeert Uytterhoeven made. 1988506f1d07SSam Ravnborg 198974ca317cSVivek Goyalconfig KEXEC_FILE 199074ca317cSVivek Goyal bool "kexec file based system call" 19912965faa5SDave Young select KEXEC_CORE 199274ca317cSVivek Goyal select BUILD_BIN2C 199374ca317cSVivek Goyal depends on X86_64 199474ca317cSVivek Goyal depends on CRYPTO=y 199574ca317cSVivek Goyal depends on CRYPTO_SHA256=y 199674ca317cSVivek Goyal ---help--- 199774ca317cSVivek Goyal This is new version of kexec system call. This system call is 199874ca317cSVivek Goyal file based and takes file descriptors as system call argument 199974ca317cSVivek Goyal for kernel and initramfs as opposed to list of segments as 200074ca317cSVivek Goyal accepted by previous system call. 200174ca317cSVivek Goyal 2002b799a09fSAKASHI Takahiroconfig ARCH_HAS_KEXEC_PURGATORY 2003b799a09fSAKASHI Takahiro def_bool KEXEC_FILE 2004b799a09fSAKASHI Takahiro 20058e7d8381SVivek Goyalconfig KEXEC_VERIFY_SIG 20068e7d8381SVivek Goyal bool "Verify kernel signature during kexec_file_load() syscall" 200774ca317cSVivek Goyal depends on KEXEC_FILE 20088e7d8381SVivek Goyal ---help--- 20098e7d8381SVivek Goyal This option makes kernel signature verification mandatory for 2010d8eb8940SBorislav Petkov the kexec_file_load() syscall. 20118e7d8381SVivek Goyal 2012d8eb8940SBorislav Petkov In addition to that option, you need to enable signature 2013d8eb8940SBorislav Petkov verification for the corresponding kernel image type being 2014d8eb8940SBorislav Petkov loaded in order for this to work. 20158e7d8381SVivek Goyal 20168e7d8381SVivek Goyalconfig KEXEC_BZIMAGE_VERIFY_SIG 20178e7d8381SVivek Goyal bool "Enable bzImage signature verification support" 20188e7d8381SVivek Goyal depends on KEXEC_VERIFY_SIG 20198e7d8381SVivek Goyal depends on SIGNED_PE_FILE_VERIFICATION 20208e7d8381SVivek Goyal select SYSTEM_TRUSTED_KEYRING 20218e7d8381SVivek Goyal ---help--- 20228e7d8381SVivek Goyal Enable bzImage signature verification support. 20238e7d8381SVivek Goyal 2024506f1d07SSam Ravnborgconfig CRASH_DUMP 202504b69447SPavel Machek bool "kernel crash dumps" 2026506f1d07SSam Ravnborg depends on X86_64 || (X86_32 && HIGHMEM) 20278f9ca475SIngo Molnar ---help--- 2028506f1d07SSam Ravnborg Generate crash dump after being started by kexec. 2029506f1d07SSam Ravnborg This should be normally only set in special crash dump kernels 2030506f1d07SSam Ravnborg which are loaded in the main kernel with kexec-tools into 2031506f1d07SSam Ravnborg a specially reserved region and then later executed after 2032506f1d07SSam Ravnborg a crash by kdump/kexec. The crash dump kernel must be compiled 2033506f1d07SSam Ravnborg to a memory address not used by the main kernel or BIOS using 2034506f1d07SSam Ravnborg PHYSICAL_START, or it must be built as a relocatable image 2035506f1d07SSam Ravnborg (CONFIG_RELOCATABLE=y). 2036506f1d07SSam Ravnborg For more details see Documentation/kdump/kdump.txt 2037506f1d07SSam Ravnborg 20383ab83521SHuang Yingconfig KEXEC_JUMP 20396ea30386SKees Cook bool "kexec jump" 2040fee7b0d8SHuang Ying depends on KEXEC && HIBERNATION 20418f9ca475SIngo Molnar ---help--- 204289081d17SHuang Ying Jump between original kernel and kexeced kernel and invoke 204389081d17SHuang Ying code in physical address mode via KEXEC 20443ab83521SHuang Ying 2045506f1d07SSam Ravnborgconfig PHYSICAL_START 20466a108a14SDavid Rientjes hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP) 2047ceefccc9SH. Peter Anvin default "0x1000000" 20488f9ca475SIngo Molnar ---help--- 2049506f1d07SSam Ravnborg This gives the physical address where the kernel is loaded. 2050506f1d07SSam Ravnborg 2051506f1d07SSam Ravnborg If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 2052506f1d07SSam Ravnborg bzImage will decompress itself to above physical address and 2053506f1d07SSam Ravnborg run from there. Otherwise, bzImage will run from the address where 2054506f1d07SSam Ravnborg it has been loaded by the boot loader and will ignore above physical 2055506f1d07SSam Ravnborg address. 2056506f1d07SSam Ravnborg 2057506f1d07SSam Ravnborg In normal kdump cases one does not have to set/change this option 2058506f1d07SSam Ravnborg as now bzImage can be compiled as a completely relocatable image 2059506f1d07SSam Ravnborg (CONFIG_RELOCATABLE=y) and be used to load and run from a different 2060506f1d07SSam Ravnborg address. This option is mainly useful for the folks who don't want 2061506f1d07SSam Ravnborg to use a bzImage for capturing the crash dump and want to use a 2062506f1d07SSam Ravnborg vmlinux instead. vmlinux is not relocatable hence a kernel needs 2063506f1d07SSam Ravnborg to be specifically compiled to run from a specific memory area 2064506f1d07SSam Ravnborg (normally a reserved region) and this option comes handy. 2065506f1d07SSam Ravnborg 2066ceefccc9SH. Peter Anvin So if you are using bzImage for capturing the crash dump, 2067ceefccc9SH. Peter Anvin leave the value here unchanged to 0x1000000 and set 2068ceefccc9SH. Peter Anvin CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux 2069ceefccc9SH. Peter Anvin for capturing the crash dump change this value to start of 2070ceefccc9SH. Peter Anvin the reserved region. In other words, it can be set based on 2071ceefccc9SH. Peter Anvin the "X" value as specified in the "crashkernel=YM@XM" 2072ceefccc9SH. Peter Anvin command line boot parameter passed to the panic-ed 2073ceefccc9SH. Peter Anvin kernel. Please take a look at Documentation/kdump/kdump.txt 2074ceefccc9SH. Peter Anvin for more details about crash dumps. 2075506f1d07SSam Ravnborg 2076506f1d07SSam Ravnborg Usage of bzImage for capturing the crash dump is recommended as 2077506f1d07SSam Ravnborg one does not have to build two kernels. Same kernel can be used 2078506f1d07SSam Ravnborg as production kernel and capture kernel. Above option should have 2079506f1d07SSam Ravnborg gone away after relocatable bzImage support is introduced. But it 2080506f1d07SSam Ravnborg is present because there are users out there who continue to use 2081506f1d07SSam Ravnborg vmlinux for dump capture. This option should go away down the 2082506f1d07SSam Ravnborg line. 2083506f1d07SSam Ravnborg 2084506f1d07SSam Ravnborg Don't change this unless you know what you are doing. 2085506f1d07SSam Ravnborg 2086506f1d07SSam Ravnborgconfig RELOCATABLE 208726717808SH. Peter Anvin bool "Build a relocatable kernel" 208826717808SH. Peter Anvin default y 20898f9ca475SIngo Molnar ---help--- 2090506f1d07SSam Ravnborg This builds a kernel image that retains relocation information 2091506f1d07SSam Ravnborg so it can be loaded someplace besides the default 1MB. 2092506f1d07SSam Ravnborg The relocations tend to make the kernel binary about 10% larger, 2093506f1d07SSam Ravnborg but are discarded at runtime. 2094506f1d07SSam Ravnborg 2095506f1d07SSam Ravnborg One use is for the kexec on panic case where the recovery kernel 2096506f1d07SSam Ravnborg must live at a different physical address than the primary 2097506f1d07SSam Ravnborg kernel. 2098506f1d07SSam Ravnborg 2099506f1d07SSam Ravnborg Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 2100506f1d07SSam Ravnborg it has been loaded at and the compile time physical address 21018ab3820fSKees Cook (CONFIG_PHYSICAL_START) is used as the minimum location. 2102506f1d07SSam Ravnborg 21038ab3820fSKees Cookconfig RANDOMIZE_BASE 2104e8581e3dSBaoquan He bool "Randomize the address of the kernel image (KASLR)" 21058ab3820fSKees Cook depends on RELOCATABLE 21066807c846SIngo Molnar default y 21078ab3820fSKees Cook ---help--- 2108e8581e3dSBaoquan He In support of Kernel Address Space Layout Randomization (KASLR), 2109e8581e3dSBaoquan He this randomizes the physical address at which the kernel image 2110e8581e3dSBaoquan He is decompressed and the virtual address where the kernel 2111e8581e3dSBaoquan He image is mapped, as a security feature that deters exploit 2112e8581e3dSBaoquan He attempts relying on knowledge of the location of kernel 2113e8581e3dSBaoquan He code internals. 2114e8581e3dSBaoquan He 2115ed9f007eSKees Cook On 64-bit, the kernel physical and virtual addresses are 2116ed9f007eSKees Cook randomized separately. The physical address will be anywhere 2117ed9f007eSKees Cook between 16MB and the top of physical memory (up to 64TB). The 2118ed9f007eSKees Cook virtual address will be randomized from 16MB up to 1GB (9 bits 2119ed9f007eSKees Cook of entropy). Note that this also reduces the memory space 2120ed9f007eSKees Cook available to kernel modules from 1.5GB to 1GB. 2121ed9f007eSKees Cook 2122ed9f007eSKees Cook On 32-bit, the kernel physical and virtual addresses are 2123ed9f007eSKees Cook randomized together. They will be randomized from 16MB up to 2124ed9f007eSKees Cook 512MB (8 bits of entropy). 21258ab3820fSKees Cook 2126a653f356SKees Cook Entropy is generated using the RDRAND instruction if it is 2127e8581e3dSBaoquan He supported. If RDTSC is supported, its value is mixed into 2128e8581e3dSBaoquan He the entropy pool as well. If neither RDRAND nor RDTSC are 2129ed9f007eSKees Cook supported, then entropy is read from the i8254 timer. The 2130ed9f007eSKees Cook usable entropy is limited by the kernel being built using 2131ed9f007eSKees Cook 2GB addressing, and that PHYSICAL_ALIGN must be at a 2132ed9f007eSKees Cook minimum of 2MB. As a result, only 10 bits of entropy are 2133ed9f007eSKees Cook theoretically possible, but the implementations are further 2134ed9f007eSKees Cook limited due to memory layouts. 2135e8581e3dSBaoquan He 21366807c846SIngo Molnar If unsure, say Y. 2137da2b6fb9SKees Cook 21388ab3820fSKees Cook# Relocation on x86 needs some additional build support 2139845adf72SH. Peter Anvinconfig X86_NEED_RELOCS 2140845adf72SH. Peter Anvin def_bool y 21418ab3820fSKees Cook depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE) 2142845adf72SH. Peter Anvin 2143506f1d07SSam Ravnborgconfig PHYSICAL_ALIGN 2144a0215061SKees Cook hex "Alignment value to which kernel should be aligned" 21458ab3820fSKees Cook default "0x200000" 2146a0215061SKees Cook range 0x2000 0x1000000 if X86_32 2147a0215061SKees Cook range 0x200000 0x1000000 if X86_64 21488f9ca475SIngo Molnar ---help--- 2149506f1d07SSam Ravnborg This value puts the alignment restrictions on physical address 2150506f1d07SSam Ravnborg where kernel is loaded and run from. Kernel is compiled for an 2151506f1d07SSam Ravnborg address which meets above alignment restriction. 2152506f1d07SSam Ravnborg 2153506f1d07SSam Ravnborg If bootloader loads the kernel at a non-aligned address and 2154506f1d07SSam Ravnborg CONFIG_RELOCATABLE is set, kernel will move itself to nearest 2155506f1d07SSam Ravnborg address aligned to above value and run from there. 2156506f1d07SSam Ravnborg 2157506f1d07SSam Ravnborg If bootloader loads the kernel at a non-aligned address and 2158506f1d07SSam Ravnborg CONFIG_RELOCATABLE is not set, kernel will ignore the run time 2159506f1d07SSam Ravnborg load address and decompress itself to the address it has been 2160506f1d07SSam Ravnborg compiled for and run from there. The address for which kernel is 2161506f1d07SSam Ravnborg compiled already meets above alignment restrictions. Hence the 2162506f1d07SSam Ravnborg end result is that kernel runs from a physical address meeting 2163506f1d07SSam Ravnborg above alignment restrictions. 2164506f1d07SSam Ravnborg 2165a0215061SKees Cook On 32-bit this value must be a multiple of 0x2000. On 64-bit 2166a0215061SKees Cook this value must be a multiple of 0x200000. 2167a0215061SKees Cook 2168506f1d07SSam Ravnborg Don't change this unless you know what you are doing. 2169506f1d07SSam Ravnborg 2170eedb92abSKirill A. Shutemovconfig DYNAMIC_MEMORY_LAYOUT 2171eedb92abSKirill A. Shutemov bool 2172eedb92abSKirill A. Shutemov ---help--- 2173eedb92abSKirill A. Shutemov This option makes base addresses of vmalloc and vmemmap as well as 2174eedb92abSKirill A. Shutemov __PAGE_OFFSET movable during boot. 2175eedb92abSKirill A. Shutemov 21760483e1faSThomas Garnierconfig RANDOMIZE_MEMORY 21770483e1faSThomas Garnier bool "Randomize the kernel memory sections" 21780483e1faSThomas Garnier depends on X86_64 21790483e1faSThomas Garnier depends on RANDOMIZE_BASE 2180eedb92abSKirill A. Shutemov select DYNAMIC_MEMORY_LAYOUT 21810483e1faSThomas Garnier default RANDOMIZE_BASE 21820483e1faSThomas Garnier ---help--- 21830483e1faSThomas Garnier Randomizes the base virtual address of kernel memory sections 21840483e1faSThomas Garnier (physical memory mapping, vmalloc & vmemmap). This security feature 21850483e1faSThomas Garnier makes exploits relying on predictable memory locations less reliable. 21860483e1faSThomas Garnier 21870483e1faSThomas Garnier The order of allocations remains unchanged. Entropy is generated in 21880483e1faSThomas Garnier the same way as RANDOMIZE_BASE. Current implementation in the optimal 21890483e1faSThomas Garnier configuration have in average 30,000 different possible virtual 21900483e1faSThomas Garnier addresses for each memory section. 21910483e1faSThomas Garnier 21926807c846SIngo Molnar If unsure, say Y. 21930483e1faSThomas Garnier 219490397a41SThomas Garnierconfig RANDOMIZE_MEMORY_PHYSICAL_PADDING 219590397a41SThomas Garnier hex "Physical memory mapping padding" if EXPERT 219690397a41SThomas Garnier depends on RANDOMIZE_MEMORY 219790397a41SThomas Garnier default "0xa" if MEMORY_HOTPLUG 219890397a41SThomas Garnier default "0x0" 219990397a41SThomas Garnier range 0x1 0x40 if MEMORY_HOTPLUG 220090397a41SThomas Garnier range 0x0 0x40 220190397a41SThomas Garnier ---help--- 220290397a41SThomas Garnier Define the padding in terabytes added to the existing physical 220390397a41SThomas Garnier memory size during kernel memory randomization. It is useful 220490397a41SThomas Garnier for memory hotplug support but reduces the entropy available for 220590397a41SThomas Garnier address randomization. 220690397a41SThomas Garnier 220790397a41SThomas Garnier If unsure, leave at the default value. 220890397a41SThomas Garnier 2209506f1d07SSam Ravnborgconfig HOTPLUG_CPU 2210bebd024eSThomas Gleixner def_bool y 221140b31360SStephen Rothwell depends on SMP 2212506f1d07SSam Ravnborg 221380aa1dffSFenghua Yuconfig BOOTPARAM_HOTPLUG_CPU0 221480aa1dffSFenghua Yu bool "Set default setting of cpu0_hotpluggable" 22152c922cd0SKees Cook depends on HOTPLUG_CPU 221680aa1dffSFenghua Yu ---help--- 221780aa1dffSFenghua Yu Set whether default state of cpu0_hotpluggable is on or off. 221880aa1dffSFenghua Yu 221980aa1dffSFenghua Yu Say Y here to enable CPU0 hotplug by default. If this switch 222080aa1dffSFenghua Yu is turned on, there is no need to give cpu0_hotplug kernel 222180aa1dffSFenghua Yu parameter and the CPU0 hotplug feature is enabled by default. 222280aa1dffSFenghua Yu 222380aa1dffSFenghua Yu Please note: there are two known CPU0 dependencies if you want 222480aa1dffSFenghua Yu to enable the CPU0 hotplug feature either by this switch or by 222580aa1dffSFenghua Yu cpu0_hotplug kernel parameter. 222680aa1dffSFenghua Yu 222780aa1dffSFenghua Yu First, resume from hibernate or suspend always starts from CPU0. 222880aa1dffSFenghua Yu So hibernate and suspend are prevented if CPU0 is offline. 222980aa1dffSFenghua Yu 223080aa1dffSFenghua Yu Second dependency is PIC interrupts always go to CPU0. CPU0 can not 223180aa1dffSFenghua Yu offline if any interrupt can not migrate out of CPU0. There may 223280aa1dffSFenghua Yu be other CPU0 dependencies. 223380aa1dffSFenghua Yu 223480aa1dffSFenghua Yu Please make sure the dependencies are under your control before 223580aa1dffSFenghua Yu you enable this feature. 223680aa1dffSFenghua Yu 223780aa1dffSFenghua Yu Say N if you don't want to enable CPU0 hotplug feature by default. 223880aa1dffSFenghua Yu You still can enable the CPU0 hotplug feature at boot by kernel 223980aa1dffSFenghua Yu parameter cpu0_hotplug. 224080aa1dffSFenghua Yu 2241a71c8bc5SFenghua Yuconfig DEBUG_HOTPLUG_CPU0 2242a71c8bc5SFenghua Yu def_bool n 2243a71c8bc5SFenghua Yu prompt "Debug CPU0 hotplug" 22442c922cd0SKees Cook depends on HOTPLUG_CPU 2245a71c8bc5SFenghua Yu ---help--- 2246a71c8bc5SFenghua Yu Enabling this option offlines CPU0 (if CPU0 can be offlined) as 2247a71c8bc5SFenghua Yu soon as possible and boots up userspace with CPU0 offlined. User 2248a71c8bc5SFenghua Yu can online CPU0 back after boot time. 2249a71c8bc5SFenghua Yu 2250a71c8bc5SFenghua Yu To debug CPU0 hotplug, you need to enable CPU0 offline/online 2251a71c8bc5SFenghua Yu feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during 2252a71c8bc5SFenghua Yu compilation or giving cpu0_hotplug kernel parameter at boot. 2253a71c8bc5SFenghua Yu 2254a71c8bc5SFenghua Yu If unsure, say N. 2255a71c8bc5SFenghua Yu 2256506f1d07SSam Ravnborgconfig COMPAT_VDSO 2257b0b49f26SAndy Lutomirski def_bool n 2258b0b49f26SAndy Lutomirski prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)" 2259953fee1dSIngo Molnar depends on COMPAT_32 22608f9ca475SIngo Molnar ---help--- 2261b0b49f26SAndy Lutomirski Certain buggy versions of glibc will crash if they are 2262b0b49f26SAndy Lutomirski presented with a 32-bit vDSO that is not mapped at the address 2263b0b49f26SAndy Lutomirski indicated in its segment table. 2264e84446deSRandy Dunlap 2265b0b49f26SAndy Lutomirski The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a 2266b0b49f26SAndy Lutomirski and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and 2267b0b49f26SAndy Lutomirski 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is 2268b0b49f26SAndy Lutomirski the only released version with the bug, but OpenSUSE 9 2269b0b49f26SAndy Lutomirski contains a buggy "glibc 2.3.2". 2270506f1d07SSam Ravnborg 2271b0b49f26SAndy Lutomirski The symptom of the bug is that everything crashes on startup, saying: 2272b0b49f26SAndy Lutomirski dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed! 2273b0b49f26SAndy Lutomirski 2274b0b49f26SAndy Lutomirski Saying Y here changes the default value of the vdso32 boot 2275b0b49f26SAndy Lutomirski option from 1 to 0, which turns off the 32-bit vDSO entirely. 2276b0b49f26SAndy Lutomirski This works around the glibc bug but hurts performance. 2277b0b49f26SAndy Lutomirski 2278b0b49f26SAndy Lutomirski If unsure, say N: if you are compiling your own kernel, you 2279b0b49f26SAndy Lutomirski are unlikely to be using a buggy version of glibc. 2280506f1d07SSam Ravnborg 22813dc33bd3SKees Cookchoice 22823dc33bd3SKees Cook prompt "vsyscall table for legacy applications" 22833dc33bd3SKees Cook depends on X86_64 22843dc33bd3SKees Cook default LEGACY_VSYSCALL_EMULATE 22853dc33bd3SKees Cook help 22863dc33bd3SKees Cook Legacy user code that does not know how to find the vDSO expects 22873dc33bd3SKees Cook to be able to issue three syscalls by calling fixed addresses in 22883dc33bd3SKees Cook kernel space. Since this location is not randomized with ASLR, 22893dc33bd3SKees Cook it can be used to assist security vulnerability exploitation. 22903dc33bd3SKees Cook 22913dc33bd3SKees Cook This setting can be changed at boot time via the kernel command 2292076ca272SAndy Lutomirski line parameter vsyscall=[emulate|none]. 22933dc33bd3SKees Cook 22943dc33bd3SKees Cook On a system with recent enough glibc (2.14 or newer) and no 22953dc33bd3SKees Cook static binaries, you can say None without a performance penalty 22963dc33bd3SKees Cook to improve security. 22973dc33bd3SKees Cook 22983dc33bd3SKees Cook If unsure, select "Emulate". 22993dc33bd3SKees Cook 23003dc33bd3SKees Cook config LEGACY_VSYSCALL_EMULATE 23013dc33bd3SKees Cook bool "Emulate" 23023dc33bd3SKees Cook help 23033dc33bd3SKees Cook The kernel traps and emulates calls into the fixed 23043dc33bd3SKees Cook vsyscall address mapping. This makes the mapping 23053dc33bd3SKees Cook non-executable, but it still contains known contents, 23063dc33bd3SKees Cook which could be used in certain rare security vulnerability 23073dc33bd3SKees Cook exploits. This configuration is recommended when userspace 23083dc33bd3SKees Cook still uses the vsyscall area. 23093dc33bd3SKees Cook 23103dc33bd3SKees Cook config LEGACY_VSYSCALL_NONE 23113dc33bd3SKees Cook bool "None" 23123dc33bd3SKees Cook help 23133dc33bd3SKees Cook There will be no vsyscall mapping at all. This will 23143dc33bd3SKees Cook eliminate any risk of ASLR bypass due to the vsyscall 23153dc33bd3SKees Cook fixed address mapping. Attempts to use the vsyscalls 23163dc33bd3SKees Cook will be reported to dmesg, so that either old or 23173dc33bd3SKees Cook malicious userspace programs can be identified. 23183dc33bd3SKees Cook 23193dc33bd3SKees Cookendchoice 23203dc33bd3SKees Cook 2321516cbf37STim Birdconfig CMDLINE_BOOL 2322516cbf37STim Bird bool "Built-in kernel command line" 23238f9ca475SIngo Molnar ---help--- 2324516cbf37STim Bird Allow for specifying boot arguments to the kernel at 2325516cbf37STim Bird build time. On some systems (e.g. embedded ones), it is 2326516cbf37STim Bird necessary or convenient to provide some or all of the 2327516cbf37STim Bird kernel boot arguments with the kernel itself (that is, 2328516cbf37STim Bird to not rely on the boot loader to provide them.) 2329516cbf37STim Bird 2330516cbf37STim Bird To compile command line arguments into the kernel, 2331516cbf37STim Bird set this option to 'Y', then fill in the 233269711ca1SSébastien Hinderer boot arguments in CONFIG_CMDLINE. 2333516cbf37STim Bird 2334516cbf37STim Bird Systems with fully functional boot loaders (i.e. non-embedded) 2335516cbf37STim Bird should leave this option set to 'N'. 2336516cbf37STim Bird 2337516cbf37STim Birdconfig CMDLINE 2338516cbf37STim Bird string "Built-in kernel command string" 2339516cbf37STim Bird depends on CMDLINE_BOOL 2340516cbf37STim Bird default "" 23418f9ca475SIngo Molnar ---help--- 2342516cbf37STim Bird Enter arguments here that should be compiled into the kernel 2343516cbf37STim Bird image and used at boot time. If the boot loader provides a 2344516cbf37STim Bird command line at boot time, it is appended to this string to 2345516cbf37STim Bird form the full kernel command line, when the system boots. 2346516cbf37STim Bird 2347516cbf37STim Bird However, you can use the CONFIG_CMDLINE_OVERRIDE option to 2348516cbf37STim Bird change this behavior. 2349516cbf37STim Bird 2350516cbf37STim Bird In most cases, the command line (whether built-in or provided 2351516cbf37STim Bird by the boot loader) should specify the device for the root 2352516cbf37STim Bird file system. 2353516cbf37STim Bird 2354516cbf37STim Birdconfig CMDLINE_OVERRIDE 2355516cbf37STim Bird bool "Built-in command line overrides boot loader arguments" 2356516cbf37STim Bird depends on CMDLINE_BOOL 23578f9ca475SIngo Molnar ---help--- 2358516cbf37STim Bird Set this option to 'Y' to have the kernel ignore the boot loader 2359516cbf37STim Bird command line, and use ONLY the built-in command line. 2360516cbf37STim Bird 2361516cbf37STim Bird This is used to work around broken boot loaders. This should 2362516cbf37STim Bird be set to 'N' under normal conditions. 2363516cbf37STim Bird 2364a5b9e5a2SAndy Lutomirskiconfig MODIFY_LDT_SYSCALL 2365a5b9e5a2SAndy Lutomirski bool "Enable the LDT (local descriptor table)" if EXPERT 2366a5b9e5a2SAndy Lutomirski default y 2367a5b9e5a2SAndy Lutomirski ---help--- 2368a5b9e5a2SAndy Lutomirski Linux can allow user programs to install a per-process x86 2369a5b9e5a2SAndy Lutomirski Local Descriptor Table (LDT) using the modify_ldt(2) system 2370a5b9e5a2SAndy Lutomirski call. This is required to run 16-bit or segmented code such as 2371a5b9e5a2SAndy Lutomirski DOSEMU or some Wine programs. It is also used by some very old 2372a5b9e5a2SAndy Lutomirski threading libraries. 2373a5b9e5a2SAndy Lutomirski 2374a5b9e5a2SAndy Lutomirski Enabling this feature adds a small amount of overhead to 2375a5b9e5a2SAndy Lutomirski context switches and increases the low-level kernel attack 2376a5b9e5a2SAndy Lutomirski surface. Disabling it removes the modify_ldt(2) system call. 2377a5b9e5a2SAndy Lutomirski 2378a5b9e5a2SAndy Lutomirski Saying 'N' here may make sense for embedded or server kernels. 2379a5b9e5a2SAndy Lutomirski 2380b700e7f0SSeth Jenningssource "kernel/livepatch/Kconfig" 2381b700e7f0SSeth Jennings 2382506f1d07SSam Ravnborgendmenu 2383506f1d07SSam Ravnborg 23843072e413SMichal Hockoconfig ARCH_HAS_ADD_PAGES 23853072e413SMichal Hocko def_bool y 23863072e413SMichal Hocko depends on X86_64 && ARCH_ENABLE_MEMORY_HOTPLUG 23873072e413SMichal Hocko 2388506f1d07SSam Ravnborgconfig ARCH_ENABLE_MEMORY_HOTPLUG 2389506f1d07SSam Ravnborg def_bool y 2390506f1d07SSam Ravnborg depends on X86_64 || (X86_32 && HIGHMEM) 2391506f1d07SSam Ravnborg 239235551053SGary Hadeconfig ARCH_ENABLE_MEMORY_HOTREMOVE 239335551053SGary Hade def_bool y 239435551053SGary Hade depends on MEMORY_HOTPLUG 239535551053SGary Hade 2396e534c7c5SLee Schermerhornconfig USE_PERCPU_NUMA_NODE_ID 2397645a7919STejun Heo def_bool y 2398e534c7c5SLee Schermerhorn depends on NUMA 2399e534c7c5SLee Schermerhorn 24009491846fSKirill A. Shutemovconfig ARCH_ENABLE_SPLIT_PMD_PTLOCK 24019491846fSKirill A. Shutemov def_bool y 24029491846fSKirill A. Shutemov depends on X86_64 || X86_PAE 24039491846fSKirill A. Shutemov 2404c177c81eSNaoya Horiguchiconfig ARCH_ENABLE_HUGEPAGE_MIGRATION 2405c177c81eSNaoya Horiguchi def_bool y 2406c177c81eSNaoya Horiguchi depends on X86_64 && HUGETLB_PAGE && MIGRATION 2407c177c81eSNaoya Horiguchi 24089c670ea3SNaoya Horiguchiconfig ARCH_ENABLE_THP_MIGRATION 24099c670ea3SNaoya Horiguchi def_bool y 24109c670ea3SNaoya Horiguchi depends on X86_64 && TRANSPARENT_HUGEPAGE 24119c670ea3SNaoya Horiguchi 2412da85f865SBjorn Helgaasmenu "Power management and ACPI options" 2413e279b6c1SSam Ravnborg 2414e279b6c1SSam Ravnborgconfig ARCH_HIBERNATION_HEADER 24153c2362e6SHarvey Harrison def_bool y 241644556530SZhimin Gu depends on HIBERNATION 2417e279b6c1SSam Ravnborg 2418e279b6c1SSam Ravnborgsource "kernel/power/Kconfig" 2419e279b6c1SSam Ravnborg 2420e279b6c1SSam Ravnborgsource "drivers/acpi/Kconfig" 2421e279b6c1SSam Ravnborg 2422efafc8b2SFeng Tangsource "drivers/sfi/Kconfig" 2423efafc8b2SFeng Tang 2424a6b68076SAndi Kleenconfig X86_APM_BOOT 24256fc108a0SJan Beulich def_bool y 2426282e5aabSPaul Bolle depends on APM 2427a6b68076SAndi Kleen 2428e279b6c1SSam Ravnborgmenuconfig APM 2429e279b6c1SSam Ravnborg tristate "APM (Advanced Power Management) BIOS support" 2430efefa6f6SIngo Molnar depends on X86_32 && PM_SLEEP 2431e279b6c1SSam Ravnborg ---help--- 2432e279b6c1SSam Ravnborg APM is a BIOS specification for saving power using several different 2433e279b6c1SSam Ravnborg techniques. This is mostly useful for battery powered laptops with 2434e279b6c1SSam Ravnborg APM compliant BIOSes. If you say Y here, the system time will be 2435e279b6c1SSam Ravnborg reset after a RESUME operation, the /proc/apm device will provide 2436e279b6c1SSam Ravnborg battery status information, and user-space programs will receive 2437e279b6c1SSam Ravnborg notification of APM "events" (e.g. battery status change). 2438e279b6c1SSam Ravnborg 2439e279b6c1SSam Ravnborg If you select "Y" here, you can disable actual use of the APM 2440e279b6c1SSam Ravnborg BIOS by passing the "apm=off" option to the kernel at boot time. 2441e279b6c1SSam Ravnborg 2442e279b6c1SSam Ravnborg Note that the APM support is almost completely disabled for 2443e279b6c1SSam Ravnborg machines with more than one CPU. 2444e279b6c1SSam Ravnborg 2445e279b6c1SSam Ravnborg In order to use APM, you will need supporting software. For location 24462dc98fd3SMichael Witten and more information, read <file:Documentation/power/apm-acpi.txt> 24472dc98fd3SMichael Witten and the Battery Powered Linux mini-HOWTO, available from 2448e279b6c1SSam Ravnborg <http://www.tldp.org/docs.html#howto>. 2449e279b6c1SSam Ravnborg 2450e279b6c1SSam Ravnborg This driver does not spin down disk drives (see the hdparm(8) 2451e279b6c1SSam Ravnborg manpage ("man 8 hdparm") for that), and it doesn't turn off 2452e279b6c1SSam Ravnborg VESA-compliant "green" monitors. 2453e279b6c1SSam Ravnborg 2454e279b6c1SSam Ravnborg This driver does not support the TI 4000M TravelMate and the ACER 2455e279b6c1SSam Ravnborg 486/DX4/75 because they don't have compliant BIOSes. Many "green" 2456e279b6c1SSam Ravnborg desktop machines also don't have compliant BIOSes, and this driver 2457e279b6c1SSam Ravnborg may cause those machines to panic during the boot phase. 2458e279b6c1SSam Ravnborg 2459e279b6c1SSam Ravnborg Generally, if you don't have a battery in your machine, there isn't 2460e279b6c1SSam Ravnborg much point in using this driver and you should say N. If you get 2461e279b6c1SSam Ravnborg random kernel OOPSes or reboots that don't seem to be related to 2462e279b6c1SSam Ravnborg anything, try disabling/enabling this option (or disabling/enabling 2463e279b6c1SSam Ravnborg APM in your BIOS). 2464e279b6c1SSam Ravnborg 2465e279b6c1SSam Ravnborg Some other things you should try when experiencing seemingly random, 2466e279b6c1SSam Ravnborg "weird" problems: 2467e279b6c1SSam Ravnborg 2468e279b6c1SSam Ravnborg 1) make sure that you have enough swap space and that it is 2469e279b6c1SSam Ravnborg enabled. 2470e279b6c1SSam Ravnborg 2) pass the "no-hlt" option to the kernel 2471e279b6c1SSam Ravnborg 3) switch on floating point emulation in the kernel and pass 2472e279b6c1SSam Ravnborg the "no387" option to the kernel 2473e279b6c1SSam Ravnborg 4) pass the "floppy=nodma" option to the kernel 2474e279b6c1SSam Ravnborg 5) pass the "mem=4M" option to the kernel (thereby disabling 2475e279b6c1SSam Ravnborg all but the first 4 MB of RAM) 2476e279b6c1SSam Ravnborg 6) make sure that the CPU is not over clocked. 2477e279b6c1SSam Ravnborg 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> 2478e279b6c1SSam Ravnborg 8) disable the cache from your BIOS settings 2479e279b6c1SSam Ravnborg 9) install a fan for the video card or exchange video RAM 2480e279b6c1SSam Ravnborg 10) install a better fan for the CPU 2481e279b6c1SSam Ravnborg 11) exchange RAM chips 2482e279b6c1SSam Ravnborg 12) exchange the motherboard. 2483e279b6c1SSam Ravnborg 2484e279b6c1SSam Ravnborg To compile this driver as a module, choose M here: the 2485e279b6c1SSam Ravnborg module will be called apm. 2486e279b6c1SSam Ravnborg 2487e279b6c1SSam Ravnborgif APM 2488e279b6c1SSam Ravnborg 2489e279b6c1SSam Ravnborgconfig APM_IGNORE_USER_SUSPEND 2490e279b6c1SSam Ravnborg bool "Ignore USER SUSPEND" 24918f9ca475SIngo Molnar ---help--- 2492e279b6c1SSam Ravnborg This option will ignore USER SUSPEND requests. On machines with a 2493e279b6c1SSam Ravnborg compliant APM BIOS, you want to say N. However, on the NEC Versa M 2494e279b6c1SSam Ravnborg series notebooks, it is necessary to say Y because of a BIOS bug. 2495e279b6c1SSam Ravnborg 2496e279b6c1SSam Ravnborgconfig APM_DO_ENABLE 2497e279b6c1SSam Ravnborg bool "Enable PM at boot time" 2498e279b6c1SSam Ravnborg ---help--- 2499e279b6c1SSam Ravnborg Enable APM features at boot time. From page 36 of the APM BIOS 2500e279b6c1SSam Ravnborg specification: "When disabled, the APM BIOS does not automatically 2501e279b6c1SSam Ravnborg power manage devices, enter the Standby State, enter the Suspend 2502e279b6c1SSam Ravnborg State, or take power saving steps in response to CPU Idle calls." 2503e279b6c1SSam Ravnborg This driver will make CPU Idle calls when Linux is idle (unless this 2504e279b6c1SSam Ravnborg feature is turned off -- see "Do CPU IDLE calls", below). This 2505e279b6c1SSam Ravnborg should always save battery power, but more complicated APM features 2506e279b6c1SSam Ravnborg will be dependent on your BIOS implementation. You may need to turn 2507e279b6c1SSam Ravnborg this option off if your computer hangs at boot time when using APM 2508e279b6c1SSam Ravnborg support, or if it beeps continuously instead of suspending. Turn 2509e279b6c1SSam Ravnborg this off if you have a NEC UltraLite Versa 33/C or a Toshiba 2510e279b6c1SSam Ravnborg T400CDT. This is off by default since most machines do fine without 2511e279b6c1SSam Ravnborg this feature. 2512e279b6c1SSam Ravnborg 2513e279b6c1SSam Ravnborgconfig APM_CPU_IDLE 2514dd8af076SLen Brown depends on CPU_IDLE 2515e279b6c1SSam Ravnborg bool "Make CPU Idle calls when idle" 25168f9ca475SIngo Molnar ---help--- 2517e279b6c1SSam Ravnborg Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. 2518e279b6c1SSam Ravnborg On some machines, this can activate improved power savings, such as 2519e279b6c1SSam Ravnborg a slowed CPU clock rate, when the machine is idle. These idle calls 2520e279b6c1SSam Ravnborg are made after the idle loop has run for some length of time (e.g., 2521e279b6c1SSam Ravnborg 333 mS). On some machines, this will cause a hang at boot time or 2522e279b6c1SSam Ravnborg whenever the CPU becomes idle. (On machines with more than one CPU, 2523e279b6c1SSam Ravnborg this option does nothing.) 2524e279b6c1SSam Ravnborg 2525e279b6c1SSam Ravnborgconfig APM_DISPLAY_BLANK 2526e279b6c1SSam Ravnborg bool "Enable console blanking using APM" 25278f9ca475SIngo Molnar ---help--- 2528e279b6c1SSam Ravnborg Enable console blanking using the APM. Some laptops can use this to 2529e279b6c1SSam Ravnborg turn off the LCD backlight when the screen blanker of the Linux 2530e279b6c1SSam Ravnborg virtual console blanks the screen. Note that this is only used by 2531e279b6c1SSam Ravnborg the virtual console screen blanker, and won't turn off the backlight 2532e279b6c1SSam Ravnborg when using the X Window system. This also doesn't have anything to 2533e279b6c1SSam Ravnborg do with your VESA-compliant power-saving monitor. Further, this 2534e279b6c1SSam Ravnborg option doesn't work for all laptops -- it might not turn off your 2535e279b6c1SSam Ravnborg backlight at all, or it might print a lot of errors to the console, 2536e279b6c1SSam Ravnborg especially if you are using gpm. 2537e279b6c1SSam Ravnborg 2538e279b6c1SSam Ravnborgconfig APM_ALLOW_INTS 2539e279b6c1SSam Ravnborg bool "Allow interrupts during APM BIOS calls" 25408f9ca475SIngo Molnar ---help--- 2541e279b6c1SSam Ravnborg Normally we disable external interrupts while we are making calls to 2542e279b6c1SSam Ravnborg the APM BIOS as a measure to lessen the effects of a badly behaving 2543e279b6c1SSam Ravnborg BIOS implementation. The BIOS should reenable interrupts if it 2544e279b6c1SSam Ravnborg needs to. Unfortunately, some BIOSes do not -- especially those in 2545e279b6c1SSam Ravnborg many of the newer IBM Thinkpads. If you experience hangs when you 2546e279b6c1SSam Ravnborg suspend, try setting this to Y. Otherwise, say N. 2547e279b6c1SSam Ravnborg 2548e279b6c1SSam Ravnborgendif # APM 2549e279b6c1SSam Ravnborg 2550bb0a56ecSDave Jonessource "drivers/cpufreq/Kconfig" 2551e279b6c1SSam Ravnborg 2552e279b6c1SSam Ravnborgsource "drivers/cpuidle/Kconfig" 2553e279b6c1SSam Ravnborg 255427471fdbSAndy Henroidsource "drivers/idle/Kconfig" 255527471fdbSAndy Henroid 2556e279b6c1SSam Ravnborgendmenu 2557e279b6c1SSam Ravnborg 2558e279b6c1SSam Ravnborg 2559e279b6c1SSam Ravnborgmenu "Bus options (PCI etc.)" 2560e279b6c1SSam Ravnborg 2561e279b6c1SSam Ravnborgchoice 2562e279b6c1SSam Ravnborg prompt "PCI access mode" 2563efefa6f6SIngo Molnar depends on X86_32 && PCI 2564e279b6c1SSam Ravnborg default PCI_GOANY 2565e279b6c1SSam Ravnborg ---help--- 2566e279b6c1SSam Ravnborg On PCI systems, the BIOS can be used to detect the PCI devices and 2567e279b6c1SSam Ravnborg determine their configuration. However, some old PCI motherboards 2568e279b6c1SSam Ravnborg have BIOS bugs and may crash if this is done. Also, some embedded 2569e279b6c1SSam Ravnborg PCI-based systems don't have any BIOS at all. Linux can also try to 2570e279b6c1SSam Ravnborg detect the PCI hardware directly without using the BIOS. 2571e279b6c1SSam Ravnborg 2572e279b6c1SSam Ravnborg With this option, you can specify how Linux should detect the 2573e279b6c1SSam Ravnborg PCI devices. If you choose "BIOS", the BIOS will be used, 2574e279b6c1SSam Ravnborg if you choose "Direct", the BIOS won't be used, and if you 2575e279b6c1SSam Ravnborg choose "MMConfig", then PCI Express MMCONFIG will be used. 2576e279b6c1SSam Ravnborg If you choose "Any", the kernel will try MMCONFIG, then the 2577e279b6c1SSam Ravnborg direct access method and falls back to the BIOS if that doesn't 2578e279b6c1SSam Ravnborg work. If unsure, go with the default, which is "Any". 2579e279b6c1SSam Ravnborg 2580e279b6c1SSam Ravnborgconfig PCI_GOBIOS 2581e279b6c1SSam Ravnborg bool "BIOS" 2582e279b6c1SSam Ravnborg 2583e279b6c1SSam Ravnborgconfig PCI_GOMMCONFIG 2584e279b6c1SSam Ravnborg bool "MMConfig" 2585e279b6c1SSam Ravnborg 2586e279b6c1SSam Ravnborgconfig PCI_GODIRECT 2587e279b6c1SSam Ravnborg bool "Direct" 2588e279b6c1SSam Ravnborg 25893ef0e1f8SAndres Salomonconfig PCI_GOOLPC 259076fb6570SDaniel Drake bool "OLPC XO-1" 25913ef0e1f8SAndres Salomon depends on OLPC 25923ef0e1f8SAndres Salomon 25932bdd1b03SAndres Salomonconfig PCI_GOANY 25942bdd1b03SAndres Salomon bool "Any" 25952bdd1b03SAndres Salomon 2596e279b6c1SSam Ravnborgendchoice 2597e279b6c1SSam Ravnborg 2598e279b6c1SSam Ravnborgconfig PCI_BIOS 25993c2362e6SHarvey Harrison def_bool y 2600efefa6f6SIngo Molnar depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY) 2601e279b6c1SSam Ravnborg 2602e279b6c1SSam Ravnborg# x86-64 doesn't support PCI BIOS access from long mode so always go direct. 2603e279b6c1SSam Ravnborgconfig PCI_DIRECT 26043c2362e6SHarvey Harrison def_bool y 26050aba496fSShaohua Li depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG)) 2606e279b6c1SSam Ravnborg 2607e279b6c1SSam Ravnborgconfig PCI_MMCONFIG 2608b45c9f36SJan Kiszka bool "Support mmconfig PCI config space access" if X86_64 2609b45c9f36SJan Kiszka default y 26108364e1f8SJan Kiszka depends on PCI && (ACPI || SFI || JAILHOUSE_GUEST) 2611b45c9f36SJan Kiszka depends on X86_64 || (PCI_GOANY || PCI_GOMMCONFIG) 2612e279b6c1SSam Ravnborg 26133ef0e1f8SAndres Salomonconfig PCI_OLPC 26142bdd1b03SAndres Salomon def_bool y 26152bdd1b03SAndres Salomon depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY) 26163ef0e1f8SAndres Salomon 2617b5401a96SAlex Nixonconfig PCI_XEN 2618b5401a96SAlex Nixon def_bool y 2619b5401a96SAlex Nixon depends on PCI && XEN 2620b5401a96SAlex Nixon select SWIOTLB_XEN 2621b5401a96SAlex Nixon 26228364e1f8SJan Kiszkaconfig MMCONF_FAM10H 26238364e1f8SJan Kiszka def_bool y 26248364e1f8SJan Kiszka depends on X86_64 && PCI_MMCONFIG && ACPI 2625e279b6c1SSam Ravnborg 26263f6ea84aSIra W. Snyderconfig PCI_CNB20LE_QUIRK 26276a108a14SDavid Rientjes bool "Read CNB20LE Host Bridge Windows" if EXPERT 26286ea30386SKees Cook depends on PCI 26293f6ea84aSIra W. Snyder help 26303f6ea84aSIra W. Snyder Read the PCI windows out of the CNB20LE host bridge. This allows 26313f6ea84aSIra W. Snyder PCI hotplug to work on systems with the CNB20LE chipset which do 26323f6ea84aSIra W. Snyder not have ACPI. 26333f6ea84aSIra W. Snyder 263464a5fed6SBjorn Helgaas There's no public spec for this chipset, and this functionality 263564a5fed6SBjorn Helgaas is known to be incomplete. 263664a5fed6SBjorn Helgaas 263764a5fed6SBjorn Helgaas You should say N unless you know you need this. 263864a5fed6SBjorn Helgaas 26393a495511SWilliam Breathitt Grayconfig ISA_BUS 264017a2a129SWilliam Breathitt Gray bool "ISA bus support on modern systems" if EXPERT 26413a495511SWilliam Breathitt Gray help 264217a2a129SWilliam Breathitt Gray Expose ISA bus device drivers and options available for selection and 264317a2a129SWilliam Breathitt Gray configuration. Enable this option if your target machine has an ISA 264417a2a129SWilliam Breathitt Gray bus. ISA is an older system, displaced by PCI and newer bus 264517a2a129SWilliam Breathitt Gray architectures -- if your target machine is modern, it probably does 264617a2a129SWilliam Breathitt Gray not have an ISA bus. 26473a495511SWilliam Breathitt Gray 26483a495511SWilliam Breathitt Gray If unsure, say N. 26493a495511SWilliam Breathitt Gray 26501c00f016SDavid Rientjes# x86_64 have no ISA slots, but can have ISA-style DMA. 2651e279b6c1SSam Ravnborgconfig ISA_DMA_API 26521c00f016SDavid Rientjes bool "ISA-style DMA support" if (X86_64 && EXPERT) 26531c00f016SDavid Rientjes default y 26541c00f016SDavid Rientjes help 26551c00f016SDavid Rientjes Enables ISA-style DMA support for devices requiring such controllers. 26561c00f016SDavid Rientjes If unsure, say Y. 2657e279b6c1SSam Ravnborg 265851e68d05SLinus Torvaldsif X86_32 265951e68d05SLinus Torvalds 2660e279b6c1SSam Ravnborgconfig ISA 2661e279b6c1SSam Ravnborg bool "ISA support" 26628f9ca475SIngo Molnar ---help--- 2663e279b6c1SSam Ravnborg Find out whether you have ISA slots on your motherboard. ISA is the 2664e279b6c1SSam Ravnborg name of a bus system, i.e. the way the CPU talks to the other stuff 2665e279b6c1SSam Ravnborg inside your box. Other bus systems are PCI, EISA, MicroChannel 2666e279b6c1SSam Ravnborg (MCA) or VESA. ISA is an older system, now being displaced by PCI; 2667e279b6c1SSam Ravnborg newer boards don't support it. If you have ISA, say Y, otherwise N. 2668e279b6c1SSam Ravnborg 2669e279b6c1SSam Ravnborgconfig SCx200 2670e279b6c1SSam Ravnborg tristate "NatSemi SCx200 support" 26718f9ca475SIngo Molnar ---help--- 2672e279b6c1SSam Ravnborg This provides basic support for National Semiconductor's 2673e279b6c1SSam Ravnborg (now AMD's) Geode processors. The driver probes for the 2674e279b6c1SSam Ravnborg PCI-IDs of several on-chip devices, so its a good dependency 2675e279b6c1SSam Ravnborg for other scx200_* drivers. 2676e279b6c1SSam Ravnborg 2677e279b6c1SSam Ravnborg If compiled as a module, the driver is named scx200. 2678e279b6c1SSam Ravnborg 2679e279b6c1SSam Ravnborgconfig SCx200HR_TIMER 2680e279b6c1SSam Ravnborg tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" 2681592913ecSJohn Stultz depends on SCx200 2682e279b6c1SSam Ravnborg default y 26838f9ca475SIngo Molnar ---help--- 2684e279b6c1SSam Ravnborg This driver provides a clocksource built upon the on-chip 2685e279b6c1SSam Ravnborg 27MHz high-resolution timer. Its also a workaround for 2686e279b6c1SSam Ravnborg NSC Geode SC-1100's buggy TSC, which loses time when the 2687e279b6c1SSam Ravnborg processor goes idle (as is done by the scheduler). The 2688e279b6c1SSam Ravnborg other workaround is idle=poll boot option. 2689e279b6c1SSam Ravnborg 26903ef0e1f8SAndres Salomonconfig OLPC 26913ef0e1f8SAndres Salomon bool "One Laptop Per Child support" 269254008979SThomas Gleixner depends on !X86_PAE 26933c554946SAndres Salomon select GPIOLIB 2694dc3119e7SThomas Gleixner select OF 269545bb1674SDaniel Drake select OF_PROMTREE 2696b4e51854SGrant Likely select IRQ_DOMAIN 26978f9ca475SIngo Molnar ---help--- 26983ef0e1f8SAndres Salomon Add support for detecting the unique features of the OLPC 26993ef0e1f8SAndres Salomon XO hardware. 27003ef0e1f8SAndres Salomon 2701a3128588SDaniel Drakeconfig OLPC_XO1_PM 2702a3128588SDaniel Drake bool "OLPC XO-1 Power Management" 2703fa112cf1SBorislav Petkov depends on OLPC && MFD_CS5535=y && PM_SLEEP 2704bf1ebf00SDaniel Drake ---help--- 270597c4cb71SDaniel Drake Add support for poweroff and suspend of the OLPC XO-1 laptop. 2706bf1ebf00SDaniel Drake 2707cfee9597SDaniel Drakeconfig OLPC_XO1_RTC 2708cfee9597SDaniel Drake bool "OLPC XO-1 Real Time Clock" 2709cfee9597SDaniel Drake depends on OLPC_XO1_PM && RTC_DRV_CMOS 2710cfee9597SDaniel Drake ---help--- 2711cfee9597SDaniel Drake Add support for the XO-1 real time clock, which can be used as a 2712cfee9597SDaniel Drake programmable wakeup source. 2713cfee9597SDaniel Drake 27147feda8e9SDaniel Drakeconfig OLPC_XO1_SCI 27157feda8e9SDaniel Drake bool "OLPC XO-1 SCI extras" 271692e830f2SArnd Bergmann depends on OLPC && OLPC_XO1_PM && GPIO_CS5535=y 2717ed8e47feSRandy Dunlap depends on INPUT=y 2718d8d01a63SDaniel Drake select POWER_SUPPLY 27197feda8e9SDaniel Drake ---help--- 27207feda8e9SDaniel Drake Add support for SCI-based features of the OLPC XO-1 laptop: 27217bc74b3dSDaniel Drake - EC-driven system wakeups 27227feda8e9SDaniel Drake - Power button 27237bc74b3dSDaniel Drake - Ebook switch 27242cf2baeaSDaniel Drake - Lid switch 2725e1040ac6SDaniel Drake - AC adapter status updates 2726e1040ac6SDaniel Drake - Battery status updates 27277feda8e9SDaniel Drake 2728a0f30f59SDaniel Drakeconfig OLPC_XO15_SCI 2729a0f30f59SDaniel Drake bool "OLPC XO-1.5 SCI extras" 2730d8d01a63SDaniel Drake depends on OLPC && ACPI 2731d8d01a63SDaniel Drake select POWER_SUPPLY 2732a0f30f59SDaniel Drake ---help--- 2733a0f30f59SDaniel Drake Add support for SCI-based features of the OLPC XO-1.5 laptop: 2734a0f30f59SDaniel Drake - EC-driven system wakeups 2735a0f30f59SDaniel Drake - AC adapter status updates 2736a0f30f59SDaniel Drake - Battery status updates 2737e279b6c1SSam Ravnborg 2738d4f3e350SEd Wildgooseconfig ALIX 2739d4f3e350SEd Wildgoose bool "PCEngines ALIX System Support (LED setup)" 2740d4f3e350SEd Wildgoose select GPIOLIB 2741d4f3e350SEd Wildgoose ---help--- 2742d4f3e350SEd Wildgoose This option enables system support for the PCEngines ALIX. 2743d4f3e350SEd Wildgoose At present this just sets up LEDs for GPIO control on 2744d4f3e350SEd Wildgoose ALIX2/3/6 boards. However, other system specific setup should 2745d4f3e350SEd Wildgoose get added here. 2746d4f3e350SEd Wildgoose 2747d4f3e350SEd Wildgoose Note: You must still enable the drivers for GPIO and LED support 2748d4f3e350SEd Wildgoose (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs 2749d4f3e350SEd Wildgoose 2750d4f3e350SEd Wildgoose Note: You have to set alix.force=1 for boards with Award BIOS. 2751d4f3e350SEd Wildgoose 2752da4e3302SPhilip Prindevilleconfig NET5501 2753da4e3302SPhilip Prindeville bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)" 2754da4e3302SPhilip Prindeville select GPIOLIB 2755da4e3302SPhilip Prindeville ---help--- 2756da4e3302SPhilip Prindeville This option enables system support for the Soekris Engineering net5501. 2757da4e3302SPhilip Prindeville 27583197059aSPhilip A. Prindevilleconfig GEOS 27593197059aSPhilip A. Prindeville bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)" 27603197059aSPhilip A. Prindeville select GPIOLIB 27613197059aSPhilip A. Prindeville depends on DMI 27623197059aSPhilip A. Prindeville ---help--- 27633197059aSPhilip A. Prindeville This option enables system support for the Traverse Technologies GEOS. 27643197059aSPhilip A. Prindeville 27657d029125SVivien Didelotconfig TS5500 27667d029125SVivien Didelot bool "Technologic Systems TS-5500 platform support" 27677d029125SVivien Didelot depends on MELAN 27687d029125SVivien Didelot select CHECK_SIGNATURE 27697d029125SVivien Didelot select NEW_LEDS 27707d029125SVivien Didelot select LEDS_CLASS 27717d029125SVivien Didelot ---help--- 27727d029125SVivien Didelot This option enables system support for the Technologic Systems TS-5500. 27737d029125SVivien Didelot 2774e279b6c1SSam Ravnborgendif # X86_32 2775e279b6c1SSam Ravnborg 277623ac4ae8SAndreas Herrmannconfig AMD_NB 2777e279b6c1SSam Ravnborg def_bool y 27780e152cd7SBorislav Petkov depends on CPU_SUP_AMD && PCI 2779e279b6c1SSam Ravnborg 2780e3263ab3SDavid Herrmannconfig X86_SYSFB 2781e3263ab3SDavid Herrmann bool "Mark VGA/VBE/EFI FB as generic system framebuffer" 2782e3263ab3SDavid Herrmann help 2783e3263ab3SDavid Herrmann Firmwares often provide initial graphics framebuffers so the BIOS, 2784e3263ab3SDavid Herrmann bootloader or kernel can show basic video-output during boot for 2785e3263ab3SDavid Herrmann user-guidance and debugging. Historically, x86 used the VESA BIOS 2786e3263ab3SDavid Herrmann Extensions and EFI-framebuffers for this, which are mostly limited 2787e3263ab3SDavid Herrmann to x86. 2788e3263ab3SDavid Herrmann This option, if enabled, marks VGA/VBE/EFI framebuffers as generic 2789e3263ab3SDavid Herrmann framebuffers so the new generic system-framebuffer drivers can be 2790e3263ab3SDavid Herrmann used on x86. If the framebuffer is not compatible with the generic 2791e3a5dc08SNikolas Nyby modes, it is advertised as fallback platform framebuffer so legacy 2792e3263ab3SDavid Herrmann drivers like efifb, vesafb and uvesafb can pick it up. 2793e3263ab3SDavid Herrmann If this option is not selected, all system framebuffers are always 2794e3263ab3SDavid Herrmann marked as fallback platform framebuffers as usual. 2795e3263ab3SDavid Herrmann 2796e3263ab3SDavid Herrmann Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will 2797e3263ab3SDavid Herrmann not be able to pick up generic system framebuffers if this option 2798e3263ab3SDavid Herrmann is selected. You are highly encouraged to enable simplefb as 2799e3263ab3SDavid Herrmann replacement if you select this option. simplefb can correctly deal 2800e3263ab3SDavid Herrmann with generic system framebuffers. But you should still keep vesafb 2801e3263ab3SDavid Herrmann and others enabled as fallback if a system framebuffer is 2802e3263ab3SDavid Herrmann incompatible with simplefb. 2803e3263ab3SDavid Herrmann 2804e3263ab3SDavid Herrmann If unsure, say Y. 2805e3263ab3SDavid Herrmann 2806e279b6c1SSam Ravnborgendmenu 2807e279b6c1SSam Ravnborg 2808e279b6c1SSam Ravnborg 28091572497cSChristoph Hellwigmenu "Binary Emulations" 2810e279b6c1SSam Ravnborg 2811e279b6c1SSam Ravnborgconfig IA32_EMULATION 2812e279b6c1SSam Ravnborg bool "IA32 Emulation" 2813e279b6c1SSam Ravnborg depends on X86_64 281439f88911SIngo Molnar select ARCH_WANT_OLD_COMPAT_IPC 2815d1603990SRandy Dunlap select BINFMT_ELF 2816a97f52e6SRoland McGrath select COMPAT_BINFMT_ELF 281739f88911SIngo Molnar select COMPAT_OLD_SIGACTION 28188f9ca475SIngo Molnar ---help--- 28195fd92e65SH. J. Lu Include code to run legacy 32-bit programs under a 28205fd92e65SH. J. Lu 64-bit kernel. You should likely turn this on, unless you're 28215fd92e65SH. J. Lu 100% sure that you don't have any 32-bit programs left. 2822e279b6c1SSam Ravnborg 2823e279b6c1SSam Ravnborgconfig IA32_AOUT 2824e279b6c1SSam Ravnborg tristate "IA32 a.out support" 28256b213e1bSDavid Woodhouse depends on IA32_EMULATION 2826eac61655SBorislav Petkov depends on BROKEN 28278f9ca475SIngo Molnar ---help--- 2828e279b6c1SSam Ravnborg Support old a.out binaries in the 32bit emulation. 2829e279b6c1SSam Ravnborg 28300bf62763SH. Peter Anvinconfig X86_X32 28316ea30386SKees Cook bool "x32 ABI for 64-bit mode" 28329b54050bSBrian Gerst depends on X86_64 28335fd92e65SH. J. Lu ---help--- 28345fd92e65SH. J. Lu Include code to run binaries for the x32 native 32-bit ABI 28355fd92e65SH. J. Lu for 64-bit processors. An x32 process gets access to the 28365fd92e65SH. J. Lu full 64-bit register file and wide data path while leaving 28375fd92e65SH. J. Lu pointers at 32 bits for smaller memory footprint. 28385fd92e65SH. J. Lu 28395fd92e65SH. J. Lu You will need a recent binutils (2.22 or later) with 28405fd92e65SH. J. Lu elf32_x86_64 support enabled to compile a kernel with this 28415fd92e65SH. J. Lu option set. 28425fd92e65SH. J. Lu 2843953fee1dSIngo Molnarconfig COMPAT_32 2844953fee1dSIngo Molnar def_bool y 2845953fee1dSIngo Molnar depends on IA32_EMULATION || X86_32 2846953fee1dSIngo Molnar select HAVE_UID16 2847953fee1dSIngo Molnar select OLD_SIGSUSPEND3 2848953fee1dSIngo Molnar 2849e279b6c1SSam Ravnborgconfig COMPAT 28503c2362e6SHarvey Harrison def_bool y 28510bf62763SH. Peter Anvin depends on IA32_EMULATION || X86_X32 2852e279b6c1SSam Ravnborg 28533120e25eSJan Beulichif COMPAT 2854e279b6c1SSam Ravnborgconfig COMPAT_FOR_U64_ALIGNMENT 28553120e25eSJan Beulich def_bool y 2856e279b6c1SSam Ravnborg 2857e279b6c1SSam Ravnborgconfig SYSVIPC_COMPAT 28583c2362e6SHarvey Harrison def_bool y 28593120e25eSJan Beulich depends on SYSVIPC 28603120e25eSJan Beulichendif 2861ee009e4aSDavid Howells 2862e279b6c1SSam Ravnborgendmenu 2863e279b6c1SSam Ravnborg 2864e279b6c1SSam Ravnborg 2865e5beae16SKeith Packardconfig HAVE_ATOMIC_IOMAP 2866e5beae16SKeith Packard def_bool y 2867e5beae16SKeith Packard depends on X86_32 2868e5beae16SKeith Packard 28694692d77fSAlessandro Rubiniconfig X86_DEV_DMA_OPS 28704692d77fSAlessandro Rubini bool 2871f7219a53SAlessandro Rubini 2872e585513bSKirill A. Shutemovconfig HAVE_GENERIC_GUP 2873e585513bSKirill A. Shutemov def_bool y 2874e585513bSKirill A. Shutemov 2875e279b6c1SSam Ravnborgsource "drivers/firmware/Kconfig" 2876e279b6c1SSam Ravnborg 2877edf88417SAvi Kivitysource "arch/x86/kvm/Kconfig" 2878