1daa93fabSSam Ravnborg# Select 32 or 64 bit 2daa93fabSSam Ravnborgconfig 64BIT 36840999bSSam Ravnborg bool "64-bit kernel" if ARCH = "x86" 4ffee0de4SDavid Woodhouse default ARCH != "i386" 58f9ca475SIngo Molnar ---help--- 6daa93fabSSam Ravnborg Say yes to build a 64-bit kernel - formerly known as x86_64 7daa93fabSSam Ravnborg Say no to build a 32-bit kernel - formerly known as i386 8daa93fabSSam Ravnborg 9daa93fabSSam Ravnborgconfig X86_32 103120e25eSJan Beulich def_bool y 113120e25eSJan Beulich depends on !64BIT 12daa93fabSSam Ravnborg 13daa93fabSSam Ravnborgconfig X86_64 143120e25eSJan Beulich def_bool y 153120e25eSJan Beulich depends on 64BIT 161032c0baSSam Ravnborg 171032c0baSSam Ravnborg### Arch settings 188d5fffb9SSam Ravnborgconfig X86 193c2362e6SHarvey Harrison def_bool y 206471b825SIngo Molnar select ACPI_LEGACY_TABLES_LOOKUP if ACPI 216e0a0ea1SGraeme Gregory select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI 226471b825SIngo Molnar select ANON_INODES 236471b825SIngo Molnar select ARCH_CLOCKSOURCE_DATA 246471b825SIngo Molnar select ARCH_DISCARD_MEMBLOCK 256471b825SIngo Molnar select ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE 26446f24d1SStephen Boyd select ARCH_HAS_DEBUG_STRICT_USER_COPY_CHECKS 2721266be9SDan Williams select ARCH_HAS_DEVMEM_IS_ALLOWED 286471b825SIngo Molnar select ARCH_HAS_ELF_RANDOMIZE 2972d93104SLinus Torvalds select ARCH_HAS_FAST_MULTIPLIER 30957e3facSRiku Voipio select ARCH_HAS_GCOV_PROFILE_ALL 3196601adbSDan Williams select ARCH_HAS_PMEM_API if X86_64 3267a3e8feSRoss Zwisler select ARCH_HAS_MMIO_FLUSH 336471b825SIngo Molnar select ARCH_HAS_SG_CHAIN 34c6d30853SAndrey Ryabinin select ARCH_HAS_UBSAN_SANITIZE_ALL 356471b825SIngo Molnar select ARCH_HAVE_NMI_SAFE_CMPXCHG 366471b825SIngo Molnar select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI 3777fbbc81SMark Salter select ARCH_MIGHT_HAVE_PC_PARPORT 385e2c18c0SMark Salter select ARCH_MIGHT_HAVE_PC_SERIO 396471b825SIngo Molnar select ARCH_SUPPORTS_ATOMIC_RMW 403b242c66SMel Gorman select ARCH_SUPPORTS_DEFERRED_STRUCT_PAGE_INIT 41be5e610cSPeter Zijlstra select ARCH_SUPPORTS_INT128 if X86_64 426471b825SIngo Molnar select ARCH_SUPPORTS_NUMA_BALANCING if X86_64 436471b825SIngo Molnar select ARCH_USE_BUILTIN_BSWAP 446471b825SIngo Molnar select ARCH_USE_CMPXCHG_LOCKREF if X86_64 456471b825SIngo Molnar select ARCH_USE_QUEUED_RWLOCKS 466471b825SIngo Molnar select ARCH_USE_QUEUED_SPINLOCKS 4772b252aeSMel Gorman select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH if SMP 485aaeb5c0SIngo Molnar select ARCH_WANTS_DYNAMIC_TASK_STRUCT 49da4276b8SIngo Molnar select ARCH_WANT_FRAME_POINTERS 506471b825SIngo Molnar select ARCH_WANT_IPC_PARSE_VERSION if X86_32 516471b825SIngo Molnar select ARCH_WANT_OPTIONAL_GPIOLIB 526471b825SIngo Molnar select BUILDTIME_EXTABLE_SORT 536471b825SIngo Molnar select CLKEVT_I8253 546471b825SIngo Molnar select CLKSRC_I8253 if X86_32 556471b825SIngo Molnar select CLOCKSOURCE_VALIDATE_LAST_CYCLE 566471b825SIngo Molnar select CLOCKSOURCE_WATCHDOG 576471b825SIngo Molnar select CLONE_BACKWARDS if X86_32 586471b825SIngo Molnar select COMPAT_OLD_SIGACTION if IA32_EMULATION 596471b825SIngo Molnar select DCACHE_WORD_ACCESS 6045471cd9SLinus Torvalds select EDAC_ATOMIC_SCRUB 6145471cd9SLinus Torvalds select EDAC_SUPPORT 626471b825SIngo Molnar select GENERIC_CLOCKEVENTS 636471b825SIngo Molnar select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC) 646471b825SIngo Molnar select GENERIC_CLOCKEVENTS_MIN_ADJUST 656471b825SIngo Molnar select GENERIC_CMOS_UPDATE 666471b825SIngo Molnar select GENERIC_CPU_AUTOPROBE 676471b825SIngo Molnar select GENERIC_EARLY_IOREMAP 686471b825SIngo Molnar select GENERIC_FIND_FIRST_BIT 696471b825SIngo Molnar select GENERIC_IOMAP 706471b825SIngo Molnar select GENERIC_IRQ_PROBE 716471b825SIngo Molnar select GENERIC_IRQ_SHOW 726471b825SIngo Molnar select GENERIC_PENDING_IRQ if SMP 736471b825SIngo Molnar select GENERIC_SMP_IDLE_THREAD 746471b825SIngo Molnar select GENERIC_STRNCPY_FROM_USER 756471b825SIngo Molnar select GENERIC_STRNLEN_USER 766471b825SIngo Molnar select GENERIC_TIME_VSYSCALL 776471b825SIngo Molnar select HAVE_ACPI_APEI if ACPI 786471b825SIngo Molnar select HAVE_ACPI_APEI_NMI if ACPI 796471b825SIngo Molnar select HAVE_ALIGNED_STRUCT_PAGE if SLUB 806471b825SIngo Molnar select HAVE_AOUT if X86_32 816471b825SIngo Molnar select HAVE_ARCH_AUDITSYSCALL 826471b825SIngo Molnar select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE 836471b825SIngo Molnar select HAVE_ARCH_JUMP_LABEL 846471b825SIngo Molnar select HAVE_ARCH_KASAN if X86_64 && SPARSEMEM_VMEMMAP 856471b825SIngo Molnar select HAVE_ARCH_KGDB 866471b825SIngo Molnar select HAVE_ARCH_KMEMCHECK 879e08f57dSDaniel Cashman select HAVE_ARCH_MMAP_RND_BITS if MMU 889e08f57dSDaniel Cashman select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT 896471b825SIngo Molnar select HAVE_ARCH_SECCOMP_FILTER 906471b825SIngo Molnar select HAVE_ARCH_SOFT_DIRTY if X86_64 916471b825SIngo Molnar select HAVE_ARCH_TRACEHOOK 926471b825SIngo Molnar select HAVE_ARCH_TRANSPARENT_HUGEPAGE 936471b825SIngo Molnar select HAVE_BPF_JIT if X86_64 946471b825SIngo Molnar select HAVE_CC_STACKPROTECTOR 956471b825SIngo Molnar select HAVE_CMPXCHG_DOUBLE 966471b825SIngo Molnar select HAVE_CMPXCHG_LOCAL 976471b825SIngo Molnar select HAVE_CONTEXT_TRACKING if X86_64 98c1bd55f9SJosh Triplett select HAVE_COPY_THREAD_TLS 996471b825SIngo Molnar select HAVE_C_RECORDMCOUNT 1006471b825SIngo Molnar select HAVE_DEBUG_KMEMLEAK 1016471b825SIngo Molnar select HAVE_DEBUG_STACKOVERFLOW 1026471b825SIngo Molnar select HAVE_DMA_API_DEBUG 1039c5a3621SAkinobu Mita select HAVE_DMA_CONTIGUOUS 104677aa9f7SSteven Rostedt select HAVE_DYNAMIC_FTRACE 10506aeaaeaSMasami Hiramatsu select HAVE_DYNAMIC_FTRACE_WITH_REGS 10658340a07SJohannes Berg select HAVE_EFFICIENT_UNALIGNED_ACCESS 1076471b825SIngo Molnar select HAVE_FENTRY if X86_64 1086471b825SIngo Molnar select HAVE_FTRACE_MCOUNT_RECORD 1096471b825SIngo Molnar select HAVE_FUNCTION_GRAPH_FP_TEST 1106471b825SIngo Molnar select HAVE_FUNCTION_GRAPH_TRACER 1116471b825SIngo Molnar select HAVE_FUNCTION_TRACER 1126471b825SIngo Molnar select HAVE_GENERIC_DMA_COHERENT if X86_32 1130067f129SK.Prasad select HAVE_HW_BREAKPOINT 1146471b825SIngo Molnar select HAVE_IDE 1156471b825SIngo Molnar select HAVE_IOREMAP_PROT 1166471b825SIngo Molnar select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64 1176471b825SIngo Molnar select HAVE_IRQ_TIME_ACCOUNTING 1186471b825SIngo Molnar select HAVE_KERNEL_BZIP2 1196471b825SIngo Molnar select HAVE_KERNEL_GZIP 1206471b825SIngo Molnar select HAVE_KERNEL_LZ4 1216471b825SIngo Molnar select HAVE_KERNEL_LZMA 1226471b825SIngo Molnar select HAVE_KERNEL_LZO 1236471b825SIngo Molnar select HAVE_KERNEL_XZ 1246471b825SIngo Molnar select HAVE_KPROBES 1256471b825SIngo Molnar select HAVE_KPROBES_ON_FTRACE 1266471b825SIngo Molnar select HAVE_KRETPROBES 1276471b825SIngo Molnar select HAVE_KVM 1286471b825SIngo Molnar select HAVE_LIVEPATCH if X86_64 1296471b825SIngo Molnar select HAVE_MEMBLOCK 1306471b825SIngo Molnar select HAVE_MEMBLOCK_NODE_MAP 1310102752eSFrederic Weisbecker select HAVE_MIXED_BREAKPOINTS_REGS 1326471b825SIngo Molnar select HAVE_OPROFILE 1336471b825SIngo Molnar select HAVE_OPTPROBES 1346471b825SIngo Molnar select HAVE_PCSPKR_PLATFORM 1356471b825SIngo Molnar select HAVE_PERF_EVENTS 136c01d4323SFrederic Weisbecker select HAVE_PERF_EVENTS_NMI 137c5e63197SJiri Olsa select HAVE_PERF_REGS 138c5ebcedbSJiri Olsa select HAVE_PERF_USER_STACK_DUMP 1396471b825SIngo Molnar select HAVE_REGS_AND_STACK_ACCESS_API 1406471b825SIngo Molnar select HAVE_SYSCALL_TRACEPOINTS 1410c3619eaSBrian Gerst select HAVE_UID16 if X86_32 || IA32_EMULATION 1426471b825SIngo Molnar select HAVE_UNSTABLE_SCHED_CLOCK 1437c68af6eSAvi Kivity select HAVE_USER_RETURN_NOTIFIER 144c0185808SThomas Gleixner select IRQ_FORCED_THREADING 145786d35d4SDavid Howells select MODULES_USE_ELF_RELA if X86_64 1466471b825SIngo Molnar select MODULES_USE_ELF_REL if X86_32 1475b3eb3adSAl Viro select OLD_SIGACTION if X86_32 1486471b825SIngo Molnar select OLD_SIGSUSPEND3 if X86_32 || IA32_EMULATION 1496471b825SIngo Molnar select PERF_EVENTS 1503195ef59SPrarit Bhargava select RTC_LIB 1516471b825SIngo Molnar select SPARSE_IRQ 15283fe27eaSPranith Kumar select SRCU 1536471b825SIngo Molnar select SYSCTL_EXCEPTION_TRACE 1546471b825SIngo Molnar select USER_STACKTRACE_SUPPORT 1556471b825SIngo Molnar select VIRT_TO_BUS 1566471b825SIngo Molnar select X86_DEV_DMA_OPS if X86_64 1576471b825SIngo Molnar select X86_FEATURE_NAMES if PROC_FS 1587d8330a5SBalbir Singh 159ba7e4d13SIngo Molnarconfig INSTRUCTION_DECODER 1603120e25eSJan Beulich def_bool y 1613120e25eSJan Beulich depends on KPROBES || PERF_EVENTS || UPROBES 162ba7e4d13SIngo Molnar 1637fb0f1deSPeter Zijlstraconfig PERF_EVENTS_INTEL_UNCORE 1647fb0f1deSPeter Zijlstra def_bool y 165ce5686d4SPeter Zijlstra (Intel) depends on PERF_EVENTS && CPU_SUP_INTEL && PCI 1667fb0f1deSPeter Zijlstra 16751b26adaSLinus Torvaldsconfig OUTPUT_FORMAT 16851b26adaSLinus Torvalds string 16951b26adaSLinus Torvalds default "elf32-i386" if X86_32 17051b26adaSLinus Torvalds default "elf64-x86-64" if X86_64 17151b26adaSLinus Torvalds 17273531905SSam Ravnborgconfig ARCH_DEFCONFIG 173b9b39bfbSSam Ravnborg string 17473531905SSam Ravnborg default "arch/x86/configs/i386_defconfig" if X86_32 17573531905SSam Ravnborg default "arch/x86/configs/x86_64_defconfig" if X86_64 176b9b39bfbSSam Ravnborg 1778d5fffb9SSam Ravnborgconfig LOCKDEP_SUPPORT 1783c2362e6SHarvey Harrison def_bool y 1798d5fffb9SSam Ravnborg 1808d5fffb9SSam Ravnborgconfig STACKTRACE_SUPPORT 1813c2362e6SHarvey Harrison def_bool y 1828d5fffb9SSam Ravnborg 1838d5fffb9SSam Ravnborgconfig MMU 1843c2362e6SHarvey Harrison def_bool y 1858d5fffb9SSam Ravnborg 1869e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_BITS_MIN 1879e08f57dSDaniel Cashman default 28 if 64BIT 1889e08f57dSDaniel Cashman default 8 1899e08f57dSDaniel Cashman 1909e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_BITS_MAX 1919e08f57dSDaniel Cashman default 32 if 64BIT 1929e08f57dSDaniel Cashman default 16 1939e08f57dSDaniel Cashman 1949e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_COMPAT_BITS_MIN 1959e08f57dSDaniel Cashman default 8 1969e08f57dSDaniel Cashman 1979e08f57dSDaniel Cashmanconfig ARCH_MMAP_RND_COMPAT_BITS_MAX 1989e08f57dSDaniel Cashman default 16 1999e08f57dSDaniel Cashman 2008d5fffb9SSam Ravnborgconfig SBUS 2018d5fffb9SSam Ravnborg bool 2028d5fffb9SSam Ravnborg 2033bc4e459SFUJITA Tomonoriconfig NEED_DMA_MAP_STATE 2043120e25eSJan Beulich def_bool y 205a6dfa128SKonrad Rzeszutek Wilk depends on X86_64 || INTEL_IOMMU || DMA_API_DEBUG || SWIOTLB 2063bc4e459SFUJITA Tomonori 20718e98307SFUJITA Tomonoriconfig NEED_SG_DMA_LENGTH 2084a14d84eSAndrew Morton def_bool y 20918e98307SFUJITA Tomonori 2108d5fffb9SSam Ravnborgconfig GENERIC_ISA_DMA 2113120e25eSJan Beulich def_bool y 2123120e25eSJan Beulich depends on ISA_DMA_API 2138d5fffb9SSam Ravnborg 2148d5fffb9SSam Ravnborgconfig GENERIC_BUG 2153c2362e6SHarvey Harrison def_bool y 2168d5fffb9SSam Ravnborg depends on BUG 217b93a531eSJan Beulich select GENERIC_BUG_RELATIVE_POINTERS if X86_64 218b93a531eSJan Beulich 219b93a531eSJan Beulichconfig GENERIC_BUG_RELATIVE_POINTERS 220b93a531eSJan Beulich bool 2218d5fffb9SSam Ravnborg 2228d5fffb9SSam Ravnborgconfig GENERIC_HWEIGHT 2233c2362e6SHarvey Harrison def_bool y 2248d5fffb9SSam Ravnborg 2258d5fffb9SSam Ravnborgconfig ARCH_MAY_HAVE_PC_FDC 2263120e25eSJan Beulich def_bool y 2273120e25eSJan Beulich depends on ISA_DMA_API 2288d5fffb9SSam Ravnborg 2291032c0baSSam Ravnborgconfig RWSEM_XCHGADD_ALGORITHM 2303120e25eSJan Beulich def_bool y 2311032c0baSSam Ravnborg 2321032c0baSSam Ravnborgconfig GENERIC_CALIBRATE_DELAY 2331032c0baSSam Ravnborg def_bool y 2341032c0baSSam Ravnborg 2359a0b8415Svenkatesh.pallipadi@intel.comconfig ARCH_HAS_CPU_RELAX 2369a0b8415Svenkatesh.pallipadi@intel.com def_bool y 2378d5fffb9SSam Ravnborg 2381b27d05bSPekka Enbergconfig ARCH_HAS_CACHE_LINE_SIZE 2391b27d05bSPekka Enberg def_bool y 2401b27d05bSPekka Enberg 241dd5af90aSMike Travisconfig HAVE_SETUP_PER_CPU_AREA 24289c9c4c5SBrian Gerst def_bool y 243b32ef636Stravis@sgi.com 24408fc4580STejun Heoconfig NEED_PER_CPU_EMBED_FIRST_CHUNK 24508fc4580STejun Heo def_bool y 24608fc4580STejun Heo 24708fc4580STejun Heoconfig NEED_PER_CPU_PAGE_FIRST_CHUNK 24811124411STejun Heo def_bool y 24911124411STejun Heo 250801e4062SJohannes Bergconfig ARCH_HIBERNATION_POSSIBLE 251801e4062SJohannes Berg def_bool y 252801e4062SJohannes Berg 253f4cb5700SJohannes Bergconfig ARCH_SUSPEND_POSSIBLE 254f4cb5700SJohannes Berg def_bool y 255f4cb5700SJohannes Berg 256cfe28c5dSSteve Capperconfig ARCH_WANT_HUGE_PMD_SHARE 257cfe28c5dSSteve Capper def_bool y 258cfe28c5dSSteve Capper 25953313b2cSSteve Capperconfig ARCH_WANT_GENERAL_HUGETLB 26053313b2cSSteve Capper def_bool y 26153313b2cSSteve Capper 2628d5fffb9SSam Ravnborgconfig ZONE_DMA32 263e0fd24a3SJan Beulich def_bool y if X86_64 2648d5fffb9SSam Ravnborg 2658d5fffb9SSam Ravnborgconfig AUDIT_ARCH 266e0fd24a3SJan Beulich def_bool y if X86_64 2678d5fffb9SSam Ravnborg 268765c68bdSIngo Molnarconfig ARCH_SUPPORTS_OPTIMIZED_INLINING 269765c68bdSIngo Molnar def_bool y 270765c68bdSIngo Molnar 2716a11f75bSAkinobu Mitaconfig ARCH_SUPPORTS_DEBUG_PAGEALLOC 2726a11f75bSAkinobu Mita def_bool y 2736a11f75bSAkinobu Mita 274d6f2d75aSAndrey Ryabininconfig KASAN_SHADOW_OFFSET 275d6f2d75aSAndrey Ryabinin hex 276d6f2d75aSAndrey Ryabinin depends on KASAN 277d6f2d75aSAndrey Ryabinin default 0xdffffc0000000000 278d6f2d75aSAndrey Ryabinin 27969575d38SShane Wangconfig HAVE_INTEL_TXT 28069575d38SShane Wang def_bool y 2816ea30386SKees Cook depends on INTEL_IOMMU && ACPI 28269575d38SShane Wang 2836b0c3d44SSam Ravnborgconfig X86_32_SMP 2846b0c3d44SSam Ravnborg def_bool y 2856b0c3d44SSam Ravnborg depends on X86_32 && SMP 2866b0c3d44SSam Ravnborg 2876b0c3d44SSam Ravnborgconfig X86_64_SMP 2886b0c3d44SSam Ravnborg def_bool y 2896b0c3d44SSam Ravnborg depends on X86_64 && SMP 2906b0c3d44SSam Ravnborg 291ccbeed3aSTejun Heoconfig X86_32_LAZY_GS 292ccbeed3aSTejun Heo def_bool y 29360a5317fSTejun Heo depends on X86_32 && !CC_STACKPROTECTOR 294ccbeed3aSTejun Heo 295d61931d8SBorislav Petkovconfig ARCH_HWEIGHT_CFLAGS 296d61931d8SBorislav Petkov string 297d61931d8SBorislav Petkov default "-fcall-saved-ecx -fcall-saved-edx" if X86_32 298d61931d8SBorislav Petkov default "-fcall-saved-rdi -fcall-saved-rsi -fcall-saved-rdx -fcall-saved-rcx -fcall-saved-r8 -fcall-saved-r9 -fcall-saved-r10 -fcall-saved-r11" if X86_64 299d61931d8SBorislav Petkov 3002b144498SSrikar Dronamrajuconfig ARCH_SUPPORTS_UPROBES 3012b144498SSrikar Dronamraju def_bool y 3022b144498SSrikar Dronamraju 303d20642f0SRob Herringconfig FIX_EARLYCON_MEM 304d20642f0SRob Herring def_bool y 305d20642f0SRob Herring 30698233368SKirill A. Shutemovconfig PGTABLE_LEVELS 30798233368SKirill A. Shutemov int 30898233368SKirill A. Shutemov default 4 if X86_64 30998233368SKirill A. Shutemov default 3 if X86_PAE 31098233368SKirill A. Shutemov default 2 31198233368SKirill A. Shutemov 312506f1d07SSam Ravnborgsource "init/Kconfig" 313dc52ddc0SMatt Helsleysource "kernel/Kconfig.freezer" 3148d5fffb9SSam Ravnborg 315506f1d07SSam Ravnborgmenu "Processor type and features" 316506f1d07SSam Ravnborg 3175ee71535SRandy Dunlapconfig ZONE_DMA 3185ee71535SRandy Dunlap bool "DMA memory allocation support" if EXPERT 3195ee71535SRandy Dunlap default y 3205ee71535SRandy Dunlap help 3215ee71535SRandy Dunlap DMA memory allocation support allows devices with less than 32-bit 3225ee71535SRandy Dunlap addressing to allocate within the first 16MB of address space. 3235ee71535SRandy Dunlap Disable if no such devices will be used. 3245ee71535SRandy Dunlap 3255ee71535SRandy Dunlap If unsure, say Y. 3265ee71535SRandy Dunlap 327506f1d07SSam Ravnborgconfig SMP 328506f1d07SSam Ravnborg bool "Symmetric multi-processing support" 329506f1d07SSam Ravnborg ---help--- 330506f1d07SSam Ravnborg This enables support for systems with more than one CPU. If you have 3314a474157SRobert Graffham a system with only one CPU, say N. If you have a system with more 3324a474157SRobert Graffham than one CPU, say Y. 333506f1d07SSam Ravnborg 3344a474157SRobert Graffham If you say N here, the kernel will run on uni- and multiprocessor 335506f1d07SSam Ravnborg machines, but will use only one CPU of a multiprocessor machine. If 336506f1d07SSam Ravnborg you say Y here, the kernel will run on many, but not all, 3374a474157SRobert Graffham uniprocessor machines. On a uniprocessor machine, the kernel 338506f1d07SSam Ravnborg will run faster if you say N here. 339506f1d07SSam Ravnborg 340506f1d07SSam Ravnborg Note that if you say Y here and choose architecture "586" or 341506f1d07SSam Ravnborg "Pentium" under "Processor family", the kernel will not work on 486 342506f1d07SSam Ravnborg architectures. Similarly, multiprocessor kernels for the "PPro" 343506f1d07SSam Ravnborg architecture may not work on all Pentium based boards. 344506f1d07SSam Ravnborg 345506f1d07SSam Ravnborg People using multiprocessor machines who say Y here should also say 346506f1d07SSam Ravnborg Y to "Enhanced Real Time Clock Support", below. The "Advanced Power 347506f1d07SSam Ravnborg Management" code will be disabled if you say Y here. 348506f1d07SSam Ravnborg 349395cf969SPaul Bolle See also <file:Documentation/x86/i386/IO-APIC.txt>, 350506f1d07SSam Ravnborg <file:Documentation/nmi_watchdog.txt> and the SMP-HOWTO available at 351506f1d07SSam Ravnborg <http://www.tldp.org/docs.html#howto>. 352506f1d07SSam Ravnborg 353506f1d07SSam Ravnborg If you don't know what to do here, say N. 354506f1d07SSam Ravnborg 3559def39beSJosh Triplettconfig X86_FEATURE_NAMES 3569def39beSJosh Triplett bool "Processor feature human-readable names" if EMBEDDED 3579def39beSJosh Triplett default y 3589def39beSJosh Triplett ---help--- 3599def39beSJosh Triplett This option compiles in a table of x86 feature bits and corresponding 3609def39beSJosh Triplett names. This is required to support /proc/cpuinfo and a few kernel 3619def39beSJosh Triplett messages. You can disable this to save space, at the expense of 3629def39beSJosh Triplett making those few kernel messages show numeric feature bits instead. 3639def39beSJosh Triplett 3649def39beSJosh Triplett If in doubt, say Y. 3659def39beSJosh Triplett 3666e1315feSBorislav Petkovconfig X86_FAST_FEATURE_TESTS 3676e1315feSBorislav Petkov bool "Fast CPU feature tests" if EMBEDDED 3686e1315feSBorislav Petkov default y 3696e1315feSBorislav Petkov ---help--- 3706e1315feSBorislav Petkov Some fast-paths in the kernel depend on the capabilities of the CPU. 3716e1315feSBorislav Petkov Say Y here for the kernel to patch in the appropriate code at runtime 3726e1315feSBorislav Petkov based on the capabilities of the CPU. The infrastructure for patching 3736e1315feSBorislav Petkov code at runtime takes up some additional space; space-constrained 3746e1315feSBorislav Petkov embedded systems may wish to say N here to produce smaller, slightly 3756e1315feSBorislav Petkov slower code. 3766e1315feSBorislav Petkov 37706cd9a7dSYinghai Luconfig X86_X2APIC 37806cd9a7dSYinghai Lu bool "Support x2apic" 37919e3d60dSJan Kiszka depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST) 38006cd9a7dSYinghai Lu ---help--- 38106cd9a7dSYinghai Lu This enables x2apic support on CPUs that have this feature. 38206cd9a7dSYinghai Lu 38306cd9a7dSYinghai Lu This allows 32-bit apic IDs (so it can support very large systems), 38406cd9a7dSYinghai Lu and accesses the local apic via MSRs not via mmio. 38506cd9a7dSYinghai Lu 38606cd9a7dSYinghai Lu If you don't know what to do here, say N. 38706cd9a7dSYinghai Lu 3886695c85bSYinghai Luconfig X86_MPPARSE 3896e87f9b7SBin Gao bool "Enable MPS table" if ACPI || SFI 3907a527688SJan Beulich default y 3915ab74722SIngo Molnar depends on X86_LOCAL_APIC 3928f9ca475SIngo Molnar ---help--- 3936695c85bSYinghai Lu For old smp systems that do not have proper acpi support. Newer systems 3946695c85bSYinghai Lu (esp with 64bit cpus) with acpi support, MADT and DSDT will override it 3956695c85bSYinghai Lu 39626f7ef14SYinghai Luconfig X86_BIGSMP 39726f7ef14SYinghai Lu bool "Support for big SMP systems with more than 8 CPUs" 39826f7ef14SYinghai Lu depends on X86_32 && SMP 3998f9ca475SIngo Molnar ---help--- 40026f7ef14SYinghai Lu This option is needed for the systems that have more than 8 CPUs 401506f1d07SSam Ravnborg 402ddd70cf9SJun Nakajimaconfig GOLDFISH 403ddd70cf9SJun Nakajima def_bool y 404ddd70cf9SJun Nakajima depends on X86_GOLDFISH 405ddd70cf9SJun Nakajima 4068425091fSRavikiran G Thirumalaiif X86_32 407c5c606d9SRavikiran G Thirumalaiconfig X86_EXTENDED_PLATFORM 408c5c606d9SRavikiran G Thirumalai bool "Support for extended (non-PC) x86 platforms" 409c5c606d9SRavikiran G Thirumalai default y 4108f9ca475SIngo Molnar ---help--- 41106ac8346SIngo Molnar If you disable this option then the kernel will only support 41206ac8346SIngo Molnar standard PC platforms. (which covers the vast majority of 41306ac8346SIngo Molnar systems out there.) 41406ac8346SIngo Molnar 4158425091fSRavikiran G Thirumalai If you enable this option then you'll be able to select support 4168425091fSRavikiran G Thirumalai for the following (non-PC) 32 bit x86 platforms: 417cb7b8023SBen Hutchings Goldfish (Android emulator) 4188425091fSRavikiran G Thirumalai AMD Elan 4198425091fSRavikiran G Thirumalai RDC R-321x SoC 4208425091fSRavikiran G Thirumalai SGI 320/540 (Visual Workstation) 42183125a3aSAlessandro Rubini STA2X11-based (e.g. Northville) 4223f4110a4SThomas Gleixner Moorestown MID devices 42306ac8346SIngo Molnar 42406ac8346SIngo Molnar If you have one of these systems, or if you want to build a 42506ac8346SIngo Molnar generic distribution kernel, say Y here - otherwise say N. 4268425091fSRavikiran G Thirumalaiendif 42706ac8346SIngo Molnar 4288425091fSRavikiran G Thirumalaiif X86_64 4298425091fSRavikiran G Thirumalaiconfig X86_EXTENDED_PLATFORM 4308425091fSRavikiran G Thirumalai bool "Support for extended (non-PC) x86 platforms" 4318425091fSRavikiran G Thirumalai default y 4328425091fSRavikiran G Thirumalai ---help--- 4338425091fSRavikiran G Thirumalai If you disable this option then the kernel will only support 4348425091fSRavikiran G Thirumalai standard PC platforms. (which covers the vast majority of 4358425091fSRavikiran G Thirumalai systems out there.) 4368425091fSRavikiran G Thirumalai 4378425091fSRavikiran G Thirumalai If you enable this option then you'll be able to select support 4388425091fSRavikiran G Thirumalai for the following (non-PC) 64 bit x86 platforms: 43944b111b5SSteffen Persvold Numascale NumaChip 4408425091fSRavikiran G Thirumalai ScaleMP vSMP 4418425091fSRavikiran G Thirumalai SGI Ultraviolet 4428425091fSRavikiran G Thirumalai 4438425091fSRavikiran G Thirumalai If you have one of these systems, or if you want to build a 4448425091fSRavikiran G Thirumalai generic distribution kernel, say Y here - otherwise say N. 4458425091fSRavikiran G Thirumalaiendif 446c5c606d9SRavikiran G Thirumalai# This is an alphabetically sorted list of 64 bit extended platforms 447c5c606d9SRavikiran G Thirumalai# Please maintain the alphabetic order if and when there are additions 44844b111b5SSteffen Persvoldconfig X86_NUMACHIP 44944b111b5SSteffen Persvold bool "Numascale NumaChip" 45044b111b5SSteffen Persvold depends on X86_64 45144b111b5SSteffen Persvold depends on X86_EXTENDED_PLATFORM 45244b111b5SSteffen Persvold depends on NUMA 45344b111b5SSteffen Persvold depends on SMP 45444b111b5SSteffen Persvold depends on X86_X2APIC 455f9726bfdSDaniel J Blueman depends on PCI_MMCONFIG 45644b111b5SSteffen Persvold ---help--- 45744b111b5SSteffen Persvold Adds support for Numascale NumaChip large-SMP systems. Needed to 45844b111b5SSteffen Persvold enable more than ~168 cores. 45944b111b5SSteffen Persvold If you don't have one of these, you should say N here. 46003b48632SNick Piggin 4616a48565eSIngo Molnarconfig X86_VSMP 462c5c606d9SRavikiran G Thirumalai bool "ScaleMP vSMP" 4636276a074SBorislav Petkov select HYPERVISOR_GUEST 4646a48565eSIngo Molnar select PARAVIRT 4656a48565eSIngo Molnar depends on X86_64 && PCI 466c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 467ead91d4bSShai Fultheim depends on SMP 4688f9ca475SIngo Molnar ---help--- 4696a48565eSIngo Molnar Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is 4706a48565eSIngo Molnar supposed to run on these EM64T-based machines. Only choose this option 4716a48565eSIngo Molnar if you have one of these machines. 4726a48565eSIngo Molnar 473c5c606d9SRavikiran G Thirumalaiconfig X86_UV 474c5c606d9SRavikiran G Thirumalai bool "SGI Ultraviolet" 475c5c606d9SRavikiran G Thirumalai depends on X86_64 476c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 47754c28d29SJack Steiner depends on NUMA 4781ecb4ae5SAndrew Morton depends on EFI 4799d6c26e7SSuresh Siddha depends on X86_X2APIC 4801222e564SIngo Molnar depends on PCI 481c5c606d9SRavikiran G Thirumalai ---help--- 482c5c606d9SRavikiran G Thirumalai This option is needed in order to support SGI Ultraviolet systems. 483c5c606d9SRavikiran G Thirumalai If you don't have one of these, you should say N here. 484c5c606d9SRavikiran G Thirumalai 485c5c606d9SRavikiran G Thirumalai# Following is an alphabetically sorted list of 32 bit extended platforms 486c5c606d9SRavikiran G Thirumalai# Please maintain the alphabetic order if and when there are additions 487506f1d07SSam Ravnborg 488ddd70cf9SJun Nakajimaconfig X86_GOLDFISH 489ddd70cf9SJun Nakajima bool "Goldfish (Virtual Platform)" 490cb7b8023SBen Hutchings depends on X86_EXTENDED_PLATFORM 491ddd70cf9SJun Nakajima ---help--- 492ddd70cf9SJun Nakajima Enable support for the Goldfish virtual platform used primarily 493ddd70cf9SJun Nakajima for Android development. Unless you are building for the Android 494ddd70cf9SJun Nakajima Goldfish emulator say N here. 495ddd70cf9SJun Nakajima 496c751e17bSThomas Gleixnerconfig X86_INTEL_CE 497c751e17bSThomas Gleixner bool "CE4100 TV platform" 498c751e17bSThomas Gleixner depends on PCI 499c751e17bSThomas Gleixner depends on PCI_GODIRECT 5006084a6e2SJiang Liu depends on X86_IO_APIC 501c751e17bSThomas Gleixner depends on X86_32 502c751e17bSThomas Gleixner depends on X86_EXTENDED_PLATFORM 50337bc9f50SDirk Brandewie select X86_REBOOTFIXUPS 504da6b737bSSebastian Andrzej Siewior select OF 505da6b737bSSebastian Andrzej Siewior select OF_EARLY_FLATTREE 506c751e17bSThomas Gleixner ---help--- 507c751e17bSThomas Gleixner Select for the Intel CE media processor (CE4100) SOC. 508c751e17bSThomas Gleixner This option compiles in support for the CE4100 SOC for settop 509c751e17bSThomas Gleixner boxes and media devices. 510c751e17bSThomas Gleixner 5114cb9b00fSDavid Cohenconfig X86_INTEL_MID 51243605ef1SAlan Cox bool "Intel MID platform support" 51343605ef1SAlan Cox depends on X86_EXTENDED_PLATFORM 514edc6bc78SDavid Cohen depends on X86_PLATFORM_DEVICES 5151ea7c673SAlan Cox depends on PCI 5163fda5bb4SAndy Shevchenko depends on X86_64 || (PCI_GOANY && X86_32) 5171ea7c673SAlan Cox depends on X86_IO_APIC 5187c9c3a1eSAlan Cox select SFI 5194cb9b00fSDavid Cohen select I2C 5207c9c3a1eSAlan Cox select DW_APB_TIMER 5211ea7c673SAlan Cox select APB_TIMER 5221ea7c673SAlan Cox select INTEL_SCU_IPC 52315a713dfSMika Westerberg select MFD_INTEL_MSIC 5241ea7c673SAlan Cox ---help--- 5254cb9b00fSDavid Cohen Select to build a kernel capable of supporting Intel MID (Mobile 5264cb9b00fSDavid Cohen Internet Device) platform systems which do not have the PCI legacy 5274cb9b00fSDavid Cohen interfaces. If you are building for a PC class system say N here. 5281ea7c673SAlan Cox 5294cb9b00fSDavid Cohen Intel MID platforms are based on an Intel processor and chipset which 5304cb9b00fSDavid Cohen consume less power than most of the x86 derivatives. 53143605ef1SAlan Cox 5328bbc2a13SBryan O'Donoghueconfig X86_INTEL_QUARK 5338bbc2a13SBryan O'Donoghue bool "Intel Quark platform support" 5348bbc2a13SBryan O'Donoghue depends on X86_32 5358bbc2a13SBryan O'Donoghue depends on X86_EXTENDED_PLATFORM 5368bbc2a13SBryan O'Donoghue depends on X86_PLATFORM_DEVICES 5378bbc2a13SBryan O'Donoghue depends on X86_TSC 5388bbc2a13SBryan O'Donoghue depends on PCI 5398bbc2a13SBryan O'Donoghue depends on PCI_GOANY 5408bbc2a13SBryan O'Donoghue depends on X86_IO_APIC 5418bbc2a13SBryan O'Donoghue select IOSF_MBI 5428bbc2a13SBryan O'Donoghue select INTEL_IMR 5439ab6eb51SAndy Shevchenko select COMMON_CLK 5448bbc2a13SBryan O'Donoghue ---help--- 5458bbc2a13SBryan O'Donoghue Select to include support for Quark X1000 SoC. 5468bbc2a13SBryan O'Donoghue Say Y here if you have a Quark based system such as the Arduino 5478bbc2a13SBryan O'Donoghue compatible Intel Galileo. 5488bbc2a13SBryan O'Donoghue 5493d48aab1SMika Westerbergconfig X86_INTEL_LPSS 5503d48aab1SMika Westerberg bool "Intel Low Power Subsystem Support" 551eebb3e8dSAndy Shevchenko depends on X86 && ACPI 5523d48aab1SMika Westerberg select COMMON_CLK 5530f531431SMathias Nyman select PINCTRL 554eebb3e8dSAndy Shevchenko select IOSF_MBI 5553d48aab1SMika Westerberg ---help--- 5563d48aab1SMika Westerberg Select to build support for Intel Low Power Subsystem such as 5573d48aab1SMika Westerberg found on Intel Lynxpoint PCH. Selecting this option enables 5580f531431SMathias Nyman things like clock tree (common clock framework) and pincontrol 5590f531431SMathias Nyman which are needed by the LPSS peripheral drivers. 5603d48aab1SMika Westerberg 56192082a88SKen Xueconfig X86_AMD_PLATFORM_DEVICE 56292082a88SKen Xue bool "AMD ACPI2Platform devices support" 56392082a88SKen Xue depends on ACPI 56492082a88SKen Xue select COMMON_CLK 56592082a88SKen Xue select PINCTRL 56692082a88SKen Xue ---help--- 56792082a88SKen Xue Select to interpret AMD specific ACPI device to platform device 56892082a88SKen Xue such as I2C, UART, GPIO found on AMD Carrizo and later chipsets. 56992082a88SKen Xue I2C and UART depend on COMMON_CLK to set clock. GPIO driver is 57092082a88SKen Xue implemented under PINCTRL subsystem. 57192082a88SKen Xue 572ced3ce76SDavid E. Boxconfig IOSF_MBI 573ced3ce76SDavid E. Box tristate "Intel SoC IOSF Sideband support for SoC platforms" 574ced3ce76SDavid E. Box depends on PCI 575ced3ce76SDavid E. Box ---help--- 576ced3ce76SDavid E. Box This option enables sideband register access support for Intel SoC 577ced3ce76SDavid E. Box platforms. On these platforms the IOSF sideband is used in lieu of 578ced3ce76SDavid E. Box MSR's for some register accesses, mostly but not limited to thermal 579ced3ce76SDavid E. Box and power. Drivers may query the availability of this device to 580ced3ce76SDavid E. Box determine if they need the sideband in order to work on these 581ced3ce76SDavid E. Box platforms. The sideband is available on the following SoC products. 582ced3ce76SDavid E. Box This list is not meant to be exclusive. 583ced3ce76SDavid E. Box - BayTrail 584ced3ce76SDavid E. Box - Braswell 585ced3ce76SDavid E. Box - Quark 586ced3ce76SDavid E. Box 587ced3ce76SDavid E. Box You should say Y if you are running a kernel on one of these SoC's. 588ced3ce76SDavid E. Box 589ed2226bdSDavid E. Boxconfig IOSF_MBI_DEBUG 590ed2226bdSDavid E. Box bool "Enable IOSF sideband access through debugfs" 591ed2226bdSDavid E. Box depends on IOSF_MBI && DEBUG_FS 592ed2226bdSDavid E. Box ---help--- 593ed2226bdSDavid E. Box Select this option to expose the IOSF sideband access registers (MCR, 594ed2226bdSDavid E. Box MDR, MCRX) through debugfs to write and read register information from 595ed2226bdSDavid E. Box different units on the SoC. This is most useful for obtaining device 596ed2226bdSDavid E. Box state information for debug and analysis. As this is a general access 597ed2226bdSDavid E. Box mechanism, users of this option would have specific knowledge of the 598ed2226bdSDavid E. Box device they want to access. 599ed2226bdSDavid E. Box 600ed2226bdSDavid E. Box If you don't require the option or are in doubt, say N. 601ed2226bdSDavid E. Box 602c5c606d9SRavikiran G Thirumalaiconfig X86_RDC321X 603c5c606d9SRavikiran G Thirumalai bool "RDC R-321x SoC" 604506f1d07SSam Ravnborg depends on X86_32 605c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 606c5c606d9SRavikiran G Thirumalai select M486 607c5c606d9SRavikiran G Thirumalai select X86_REBOOTFIXUPS 608c5c606d9SRavikiran G Thirumalai ---help--- 609c5c606d9SRavikiran G Thirumalai This option is needed for RDC R-321x system-on-chip, also known 610c5c606d9SRavikiran G Thirumalai as R-8610-(G). 611c5c606d9SRavikiran G Thirumalai If you don't have one of these chips, you should say N here. 612c5c606d9SRavikiran G Thirumalai 613e0c7ae37SIngo Molnarconfig X86_32_NON_STANDARD 6149c398017SIngo Molnar bool "Support non-standard 32-bit SMP architectures" 6159c398017SIngo Molnar depends on X86_32 && SMP 616c5c606d9SRavikiran G Thirumalai depends on X86_EXTENDED_PLATFORM 6178f9ca475SIngo Molnar ---help--- 618b5660ba7SH. Peter Anvin This option compiles in the bigsmp and STA2X11 default 619b5660ba7SH. Peter Anvin subarchitectures. It is intended for a generic binary 620b5660ba7SH. Peter Anvin kernel. If you select them all, kernel will probe it one by 621b5660ba7SH. Peter Anvin one and will fallback to default. 622d49c4288SYinghai Lu 623c5c606d9SRavikiran G Thirumalai# Alphabetically sorted list of Non standard 32 bit platforms 624d49c4288SYinghai Lu 625d949f36fSLinus Torvaldsconfig X86_SUPPORTS_MEMORY_FAILURE 6266fc108a0SJan Beulich def_bool y 627d949f36fSLinus Torvalds # MCE code calls memory_failure(): 628d949f36fSLinus Torvalds depends on X86_MCE 629d949f36fSLinus Torvalds # On 32-bit this adds too big of NODES_SHIFT and we run out of page flags: 630d949f36fSLinus Torvalds # On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH: 631d949f36fSLinus Torvalds depends on X86_64 || !SPARSEMEM 632d949f36fSLinus Torvalds select ARCH_SUPPORTS_MEMORY_FAILURE 633d949f36fSLinus Torvalds 63483125a3aSAlessandro Rubiniconfig STA2X11 63583125a3aSAlessandro Rubini bool "STA2X11 Companion Chip Support" 63683125a3aSAlessandro Rubini depends on X86_32_NON_STANDARD && PCI 63783125a3aSAlessandro Rubini select X86_DEV_DMA_OPS 63883125a3aSAlessandro Rubini select X86_DMA_REMAP 63983125a3aSAlessandro Rubini select SWIOTLB 64083125a3aSAlessandro Rubini select MFD_STA2X11 64183125a3aSAlessandro Rubini select ARCH_REQUIRE_GPIOLIB 64283125a3aSAlessandro Rubini default n 64383125a3aSAlessandro Rubini ---help--- 64483125a3aSAlessandro Rubini This adds support for boards based on the STA2X11 IO-Hub, 64583125a3aSAlessandro Rubini a.k.a. "ConneXt". The chip is used in place of the standard 64683125a3aSAlessandro Rubini PC chipset, so all "standard" peripherals are missing. If this 64783125a3aSAlessandro Rubini option is selected the kernel will still be able to boot on 64883125a3aSAlessandro Rubini standard PC machines. 64983125a3aSAlessandro Rubini 65082148d1dSShérabconfig X86_32_IRIS 65182148d1dSShérab tristate "Eurobraille/Iris poweroff module" 65282148d1dSShérab depends on X86_32 65382148d1dSShérab ---help--- 65482148d1dSShérab The Iris machines from EuroBraille do not have APM or ACPI support 65582148d1dSShérab to shut themselves down properly. A special I/O sequence is 65682148d1dSShérab needed to do so, which is what this module does at 65782148d1dSShérab kernel shutdown. 65882148d1dSShérab 65982148d1dSShérab This is only for Iris machines from EuroBraille. 66082148d1dSShérab 66182148d1dSShérab If unused, say N. 66282148d1dSShérab 663ae1e9130SIngo Molnarconfig SCHED_OMIT_FRAME_POINTER 6643c2362e6SHarvey Harrison def_bool y 6653c2362e6SHarvey Harrison prompt "Single-depth WCHAN output" 666a87d0914SKen Chen depends on X86 6678f9ca475SIngo Molnar ---help--- 668506f1d07SSam Ravnborg Calculate simpler /proc/<PID>/wchan values. If this option 669506f1d07SSam Ravnborg is disabled then wchan values will recurse back to the 670506f1d07SSam Ravnborg caller function. This provides more accurate wchan values, 671506f1d07SSam Ravnborg at the expense of slightly more scheduling overhead. 672506f1d07SSam Ravnborg 673506f1d07SSam Ravnborg If in doubt, say "Y". 674506f1d07SSam Ravnborg 6756276a074SBorislav Petkovmenuconfig HYPERVISOR_GUEST 6766276a074SBorislav Petkov bool "Linux guest support" 6778f9ca475SIngo Molnar ---help--- 6786276a074SBorislav Petkov Say Y here to enable options for running Linux under various hyper- 6796276a074SBorislav Petkov visors. This option enables basic hypervisor detection and platform 6806276a074SBorislav Petkov setup. 681506f1d07SSam Ravnborg 6826276a074SBorislav Petkov If you say N, all options in this submenu will be skipped and 6836276a074SBorislav Petkov disabled, and Linux guest support won't be built in. 684506f1d07SSam Ravnborg 6856276a074SBorislav Petkovif HYPERVISOR_GUEST 686506f1d07SSam Ravnborg 687e61bd94aSEduardo Pereira Habkostconfig PARAVIRT 688e61bd94aSEduardo Pereira Habkost bool "Enable paravirtualization code" 6898f9ca475SIngo Molnar ---help--- 690e61bd94aSEduardo Pereira Habkost This changes the kernel so it can modify itself when it is run 691e61bd94aSEduardo Pereira Habkost under a hypervisor, potentially improving performance significantly 692e61bd94aSEduardo Pereira Habkost over full virtualization. However, when run without a hypervisor 693e61bd94aSEduardo Pereira Habkost the kernel is theoretically slower and slightly larger. 694e61bd94aSEduardo Pereira Habkost 6956276a074SBorislav Petkovconfig PARAVIRT_DEBUG 6966276a074SBorislav Petkov bool "paravirt-ops debugging" 6976276a074SBorislav Petkov depends on PARAVIRT && DEBUG_KERNEL 6986276a074SBorislav Petkov ---help--- 6996276a074SBorislav Petkov Enable to debug paravirt_ops internals. Specifically, BUG if 7006276a074SBorislav Petkov a paravirt_op is missing when it is called. 7016276a074SBorislav Petkov 702b4ecc126SJeremy Fitzhardingeconfig PARAVIRT_SPINLOCKS 703b4ecc126SJeremy Fitzhardinge bool "Paravirtualization layer for spinlocks" 7046ea30386SKees Cook depends on PARAVIRT && SMP 70562c7a1e9SIngo Molnar select UNINLINE_SPIN_UNLOCK if !QUEUED_SPINLOCKS 706b4ecc126SJeremy Fitzhardinge ---help--- 707b4ecc126SJeremy Fitzhardinge Paravirtualized spinlocks allow a pvops backend to replace the 708b4ecc126SJeremy Fitzhardinge spinlock implementation with something virtualization-friendly 709b4ecc126SJeremy Fitzhardinge (for example, block the virtual CPU rather than spinning). 710b4ecc126SJeremy Fitzhardinge 7114c4e4f61SRaghavendra K T It has a minimal impact on native kernels and gives a nice performance 7124c4e4f61SRaghavendra K T benefit on paravirtualized KVM / Xen kernels. 713b4ecc126SJeremy Fitzhardinge 7144c4e4f61SRaghavendra K T If you are unsure how to answer this question, answer Y. 715b4ecc126SJeremy Fitzhardinge 71645e898b7SWaiman Longconfig QUEUED_LOCK_STAT 71745e898b7SWaiman Long bool "Paravirt queued spinlock statistics" 71845e898b7SWaiman Long depends on PARAVIRT_SPINLOCKS && DEBUG_FS && QUEUED_SPINLOCKS 71945e898b7SWaiman Long ---help--- 72045e898b7SWaiman Long Enable the collection of statistical data on the slowpath 72145e898b7SWaiman Long behavior of paravirtualized queued spinlocks and report 72245e898b7SWaiman Long them on debugfs. 72345e898b7SWaiman Long 7246276a074SBorislav Petkovsource "arch/x86/xen/Kconfig" 7256276a074SBorislav Petkov 7266276a074SBorislav Petkovconfig KVM_GUEST 7276276a074SBorislav Petkov bool "KVM Guest support (including kvmclock)" 7286276a074SBorislav Petkov depends on PARAVIRT 7296276a074SBorislav Petkov select PARAVIRT_CLOCK 7306276a074SBorislav Petkov default y 7316276a074SBorislav Petkov ---help--- 7326276a074SBorislav Petkov This option enables various optimizations for running under the KVM 7336276a074SBorislav Petkov hypervisor. It includes a paravirtualized clock, so that instead 7346276a074SBorislav Petkov of relying on a PIT (or probably other) emulation by the 7356276a074SBorislav Petkov underlying device model, the host provides the guest with 7366276a074SBorislav Petkov timing infrastructure such as time of day, and system time 7376276a074SBorislav Petkov 7381e20eb85SSrivatsa Vaddagiriconfig KVM_DEBUG_FS 7391e20eb85SSrivatsa Vaddagiri bool "Enable debug information for KVM Guests in debugfs" 7401e20eb85SSrivatsa Vaddagiri depends on KVM_GUEST && DEBUG_FS 7411e20eb85SSrivatsa Vaddagiri default n 7421e20eb85SSrivatsa Vaddagiri ---help--- 7431e20eb85SSrivatsa Vaddagiri This option enables collection of various statistics for KVM guest. 7441e20eb85SSrivatsa Vaddagiri Statistics are displayed in debugfs filesystem. Enabling this option 7451e20eb85SSrivatsa Vaddagiri may incur significant overhead. 7461e20eb85SSrivatsa Vaddagiri 7476276a074SBorislav Petkovsource "arch/x86/lguest/Kconfig" 7486276a074SBorislav Petkov 7496276a074SBorislav Petkovconfig PARAVIRT_TIME_ACCOUNTING 7506276a074SBorislav Petkov bool "Paravirtual steal time accounting" 7516276a074SBorislav Petkov depends on PARAVIRT 7526276a074SBorislav Petkov default n 7536276a074SBorislav Petkov ---help--- 7546276a074SBorislav Petkov Select this option to enable fine granularity task steal time 7556276a074SBorislav Petkov accounting. Time spent executing other tasks in parallel with 7566276a074SBorislav Petkov the current vCPU is discounted from the vCPU power. To account for 7576276a074SBorislav Petkov that, there can be a small performance impact. 7586276a074SBorislav Petkov 7596276a074SBorislav Petkov If in doubt, say N here. 7606276a074SBorislav Petkov 7617af192c9SGerd Hoffmannconfig PARAVIRT_CLOCK 7627af192c9SGerd Hoffmann bool 7637af192c9SGerd Hoffmann 7646276a074SBorislav Petkovendif #HYPERVISOR_GUEST 76597349135SJeremy Fitzhardinge 76608677214SYinghai Luconfig NO_BOOTMEM 767774ea0bcSYinghai Lu def_bool y 76808677214SYinghai Lu 769506f1d07SSam Ravnborgsource "arch/x86/Kconfig.cpu" 770506f1d07SSam Ravnborg 771506f1d07SSam Ravnborgconfig HPET_TIMER 7723c2362e6SHarvey Harrison def_bool X86_64 773506f1d07SSam Ravnborg prompt "HPET Timer Support" if X86_32 7748f9ca475SIngo Molnar ---help--- 775506f1d07SSam Ravnborg Use the IA-PC HPET (High Precision Event Timer) to manage 776506f1d07SSam Ravnborg time in preference to the PIT and RTC, if a HPET is 777506f1d07SSam Ravnborg present. 778506f1d07SSam Ravnborg HPET is the next generation timer replacing legacy 8254s. 779506f1d07SSam Ravnborg The HPET provides a stable time base on SMP 780506f1d07SSam Ravnborg systems, unlike the TSC, but it is more expensive to access, 781506f1d07SSam Ravnborg as it is off-chip. You can find the HPET spec at 782e45f2c07SDenis V. Lunev <http://www.intel.com/hardwaredesign/hpetspec_1.pdf>. 783506f1d07SSam Ravnborg 784506f1d07SSam Ravnborg You can safely choose Y here. However, HPET will only be 785506f1d07SSam Ravnborg activated if the platform and the BIOS support this feature. 786506f1d07SSam Ravnborg Otherwise the 8254 will be used for timing services. 787506f1d07SSam Ravnborg 788506f1d07SSam Ravnborg Choose N to continue using the legacy 8254 timer. 789506f1d07SSam Ravnborg 790506f1d07SSam Ravnborgconfig HPET_EMULATE_RTC 7913c2362e6SHarvey Harrison def_bool y 7929d8af78bSBernhard Walle depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y) 793506f1d07SSam Ravnborg 794bb24c471SJacob Panconfig APB_TIMER 795933b9463SAlan Cox def_bool y if X86_INTEL_MID 796933b9463SAlan Cox prompt "Intel MID APB Timer Support" if X86_INTEL_MID 79706c3df49SJamie Iles select DW_APB_TIMER 798a0c3832aSAlan Cox depends on X86_INTEL_MID && SFI 799bb24c471SJacob Pan help 800bb24c471SJacob Pan APB timer is the replacement for 8254, HPET on X86 MID platforms. 801bb24c471SJacob Pan The APBT provides a stable time base on SMP 802bb24c471SJacob Pan systems, unlike the TSC, but it is more expensive to access, 803bb24c471SJacob Pan as it is off-chip. APB timers are always running regardless of CPU 804bb24c471SJacob Pan C states, they are used as per CPU clockevent device when possible. 805bb24c471SJacob Pan 8066a108a14SDavid Rientjes# Mark as expert because too many people got it wrong. 807506f1d07SSam Ravnborg# The code disables itself when not needed. 8087ae9392cSThomas Petazzoniconfig DMI 8097ae9392cSThomas Petazzoni default y 810cf074402SArd Biesheuvel select DMI_SCAN_MACHINE_NON_EFI_FALLBACK 8116a108a14SDavid Rientjes bool "Enable DMI scanning" if EXPERT 8128f9ca475SIngo Molnar ---help--- 8137ae9392cSThomas Petazzoni Enabled scanning of DMI to identify machine quirks. Say Y 8147ae9392cSThomas Petazzoni here unless you have verified that your setup is not 8157ae9392cSThomas Petazzoni affected by entries in the DMI blacklist. Required by PNP 8167ae9392cSThomas Petazzoni BIOS code. 8177ae9392cSThomas Petazzoni 818506f1d07SSam Ravnborgconfig GART_IOMMU 81938901f1cSAndi Kleen bool "Old AMD GART IOMMU support" 820506f1d07SSam Ravnborg select SWIOTLB 82123ac4ae8SAndreas Herrmann depends on X86_64 && PCI && AMD_NB 8228f9ca475SIngo Molnar ---help--- 823ced3c42cSIngo Molnar Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron 824ced3c42cSIngo Molnar GART based hardware IOMMUs. 825ced3c42cSIngo Molnar 826ced3c42cSIngo Molnar The GART supports full DMA access for devices with 32-bit access 827ced3c42cSIngo Molnar limitations, on systems with more than 3 GB. This is usually needed 828ced3c42cSIngo Molnar for USB, sound, many IDE/SATA chipsets and some other devices. 829ced3c42cSIngo Molnar 830ced3c42cSIngo Molnar Newer systems typically have a modern AMD IOMMU, supported via 831ced3c42cSIngo Molnar the CONFIG_AMD_IOMMU=y config option. 832ced3c42cSIngo Molnar 833ced3c42cSIngo Molnar In normal configurations this driver is only active when needed: 834ced3c42cSIngo Molnar there's more than 3 GB of memory and the system contains a 835ced3c42cSIngo Molnar 32-bit limited device. 836ced3c42cSIngo Molnar 837ced3c42cSIngo Molnar If unsure, say Y. 838506f1d07SSam Ravnborg 839506f1d07SSam Ravnborgconfig CALGARY_IOMMU 840506f1d07SSam Ravnborg bool "IBM Calgary IOMMU support" 841506f1d07SSam Ravnborg select SWIOTLB 8426ea30386SKees Cook depends on X86_64 && PCI 8438f9ca475SIngo Molnar ---help--- 844506f1d07SSam Ravnborg Support for hardware IOMMUs in IBM's xSeries x366 and x460 845506f1d07SSam Ravnborg systems. Needed to run systems with more than 3GB of memory 846506f1d07SSam Ravnborg properly with 32-bit PCI devices that do not support DAC 847506f1d07SSam Ravnborg (Double Address Cycle). Calgary also supports bus level 848506f1d07SSam Ravnborg isolation, where all DMAs pass through the IOMMU. This 849506f1d07SSam Ravnborg prevents them from going anywhere except their intended 850506f1d07SSam Ravnborg destination. This catches hard-to-find kernel bugs and 851506f1d07SSam Ravnborg mis-behaving drivers and devices that do not use the DMA-API 852506f1d07SSam Ravnborg properly to set up their DMA buffers. The IOMMU can be 853506f1d07SSam Ravnborg turned off at boot time with the iommu=off parameter. 854506f1d07SSam Ravnborg Normally the kernel will make the right choice by itself. 855506f1d07SSam Ravnborg If unsure, say Y. 856506f1d07SSam Ravnborg 857506f1d07SSam Ravnborgconfig CALGARY_IOMMU_ENABLED_BY_DEFAULT 8583c2362e6SHarvey Harrison def_bool y 8593c2362e6SHarvey Harrison prompt "Should Calgary be enabled by default?" 860506f1d07SSam Ravnborg depends on CALGARY_IOMMU 8618f9ca475SIngo Molnar ---help--- 862506f1d07SSam Ravnborg Should Calgary be enabled by default? if you choose 'y', Calgary 863506f1d07SSam Ravnborg will be used (if it exists). If you choose 'n', Calgary will not be 864506f1d07SSam Ravnborg used even if it exists. If you choose 'n' and would like to use 865506f1d07SSam Ravnborg Calgary anyway, pass 'iommu=calgary' on the kernel command line. 866506f1d07SSam Ravnborg If unsure, say Y. 867506f1d07SSam Ravnborg 868506f1d07SSam Ravnborg# need this always selected by IOMMU for the VIA workaround 869506f1d07SSam Ravnborgconfig SWIOTLB 870a1afd01cSJoerg Roedel def_bool y if X86_64 8718f9ca475SIngo Molnar ---help--- 872506f1d07SSam Ravnborg Support for software bounce buffers used on x86-64 systems 8734454d327SJoe Millenbach which don't have a hardware IOMMU. Using this PCI devices 8744454d327SJoe Millenbach which can only access 32-bits of memory can be used on systems 8754454d327SJoe Millenbach with more than 3 GB of memory. 8764454d327SJoe Millenbach If unsure, say Y. 877506f1d07SSam Ravnborg 878a8522509SFUJITA Tomonoriconfig IOMMU_HELPER 8793120e25eSJan Beulich def_bool y 8803120e25eSJan Beulich depends on CALGARY_IOMMU || GART_IOMMU || SWIOTLB || AMD_IOMMU 881d25e26b6SLinus Torvalds 8821184dc2fSMike Travisconfig MAXSMP 883ddb0c5a6SSamuel Thibault bool "Enable Maximum number of SMP Processors and NUMA Nodes" 8846ea30386SKees Cook depends on X86_64 && SMP && DEBUG_KERNEL 88536f5101aSMike Travis select CPUMASK_OFFSTACK 8868f9ca475SIngo Molnar ---help--- 887ddb0c5a6SSamuel Thibault Enable maximum number of CPUS and NUMA Nodes for this architecture. 8881184dc2fSMike Travis If unsure, say N. 889506f1d07SSam Ravnborg 890506f1d07SSam Ravnborgconfig NR_CPUS 89136f5101aSMike Travis int "Maximum number of CPUs" if SMP && !MAXSMP 8922a3313f4SMichael K. Johnson range 2 8 if SMP && X86_32 && !X86_BIGSMP 893bb61ccc7SJosh Boyer range 2 512 if SMP && !MAXSMP && !CPUMASK_OFFSTACK 894b53b5edaSJosh Boyer range 2 8192 if SMP && !MAXSMP && CPUMASK_OFFSTACK && X86_64 89578637a97SMike Travis default "1" if !SMP 896b53b5edaSJosh Boyer default "8192" if MAXSMP 897b5660ba7SH. Peter Anvin default "32" if SMP && X86_BIGSMP 898c5c19941SKirill A. Shutemov default "8" if SMP && X86_32 899c5c19941SKirill A. Shutemov default "64" if SMP 9008f9ca475SIngo Molnar ---help--- 901506f1d07SSam Ravnborg This allows you to specify the maximum number of CPUs which this 902bb61ccc7SJosh Boyer kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum 903cad14bb9SKirill A. Shutemov supported value is 8192, otherwise the maximum value is 512. The 904506f1d07SSam Ravnborg minimum value which makes sense is 2. 905506f1d07SSam Ravnborg 906506f1d07SSam Ravnborg This is purely to save memory - each supported CPU adds 907506f1d07SSam Ravnborg approximately eight kilobytes to the kernel image. 908506f1d07SSam Ravnborg 909506f1d07SSam Ravnborgconfig SCHED_SMT 910506f1d07SSam Ravnborg bool "SMT (Hyperthreading) scheduler support" 911c8e56d20SBorislav Petkov depends on SMP 9128f9ca475SIngo Molnar ---help--- 913506f1d07SSam Ravnborg SMT scheduler support improves the CPU scheduler's decision making 914506f1d07SSam Ravnborg when dealing with Intel Pentium 4 chips with HyperThreading at a 915506f1d07SSam Ravnborg cost of slightly increased overhead in some places. If unsure say 916506f1d07SSam Ravnborg N here. 917506f1d07SSam Ravnborg 918506f1d07SSam Ravnborgconfig SCHED_MC 9193c2362e6SHarvey Harrison def_bool y 9203c2362e6SHarvey Harrison prompt "Multi-core scheduler support" 921c8e56d20SBorislav Petkov depends on SMP 9228f9ca475SIngo Molnar ---help--- 923506f1d07SSam Ravnborg Multi-core scheduler support improves the CPU scheduler's decision 924506f1d07SSam Ravnborg making when dealing with multi-core CPU chips at a cost of slightly 925506f1d07SSam Ravnborg increased overhead in some places. If unsure say N here. 926506f1d07SSam Ravnborg 927506f1d07SSam Ravnborgsource "kernel/Kconfig.preempt" 928506f1d07SSam Ravnborg 92930b8b006SThomas Gleixnerconfig UP_LATE_INIT 93030b8b006SThomas Gleixner def_bool y 931ba360f88SThomas Gleixner depends on !SMP && X86_LOCAL_APIC 93230b8b006SThomas Gleixner 933506f1d07SSam Ravnborgconfig X86_UP_APIC 93450849eefSJan Beulich bool "Local APIC support on uniprocessors" if !PCI_MSI 93550849eefSJan Beulich default PCI_MSI 93638a1dfdaSBryan O'Donoghue depends on X86_32 && !SMP && !X86_32_NON_STANDARD 9378f9ca475SIngo Molnar ---help--- 938506f1d07SSam Ravnborg A local APIC (Advanced Programmable Interrupt Controller) is an 939506f1d07SSam Ravnborg integrated interrupt controller in the CPU. If you have a single-CPU 940506f1d07SSam Ravnborg system which has a processor with a local APIC, you can say Y here to 941506f1d07SSam Ravnborg enable and use it. If you say Y here even though your machine doesn't 942506f1d07SSam Ravnborg have a local APIC, then the kernel will still run with no slowdown at 943506f1d07SSam Ravnborg all. The local APIC supports CPU-generated self-interrupts (timer, 944506f1d07SSam Ravnborg performance counters), and the NMI watchdog which detects hard 945506f1d07SSam Ravnborg lockups. 946506f1d07SSam Ravnborg 947506f1d07SSam Ravnborgconfig X86_UP_IOAPIC 948506f1d07SSam Ravnborg bool "IO-APIC support on uniprocessors" 949506f1d07SSam Ravnborg depends on X86_UP_APIC 9508f9ca475SIngo Molnar ---help--- 951506f1d07SSam Ravnborg An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an 952506f1d07SSam Ravnborg SMP-capable replacement for PC-style interrupt controllers. Most 953506f1d07SSam Ravnborg SMP systems and many recent uniprocessor systems have one. 954506f1d07SSam Ravnborg 955506f1d07SSam Ravnborg If you have a single-CPU system with an IO-APIC, you can say Y here 956506f1d07SSam Ravnborg to use it. If you say Y here even though your machine doesn't have 957506f1d07SSam Ravnborg an IO-APIC, then the kernel will still run with no slowdown at all. 958506f1d07SSam Ravnborg 959506f1d07SSam Ravnborgconfig X86_LOCAL_APIC 9603c2362e6SHarvey Harrison def_bool y 9610dbc6078SThomas Petazzoni depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI 962b5dc8e6cSJiang Liu select IRQ_DOMAIN_HIERARCHY 96352f518a3SJiang Liu select PCI_MSI_IRQ_DOMAIN if PCI_MSI 964506f1d07SSam Ravnborg 965506f1d07SSam Ravnborgconfig X86_IO_APIC 966b1da1e71SJan Beulich def_bool y 967b1da1e71SJan Beulich depends on X86_LOCAL_APIC || X86_UP_IOAPIC 968506f1d07SSam Ravnborg 96941b9eb26SStefan Assmannconfig X86_REROUTE_FOR_BROKEN_BOOT_IRQS 97041b9eb26SStefan Assmann bool "Reroute for broken boot IRQs" 97141b9eb26SStefan Assmann depends on X86_IO_APIC 9728f9ca475SIngo Molnar ---help--- 97341b9eb26SStefan Assmann This option enables a workaround that fixes a source of 97441b9eb26SStefan Assmann spurious interrupts. This is recommended when threaded 97541b9eb26SStefan Assmann interrupt handling is used on systems where the generation of 97641b9eb26SStefan Assmann superfluous "boot interrupts" cannot be disabled. 97741b9eb26SStefan Assmann 97841b9eb26SStefan Assmann Some chipsets generate a legacy INTx "boot IRQ" when the IRQ 97941b9eb26SStefan Assmann entry in the chipset's IO-APIC is masked (as, e.g. the RT 98041b9eb26SStefan Assmann kernel does during interrupt handling). On chipsets where this 98141b9eb26SStefan Assmann boot IRQ generation cannot be disabled, this workaround keeps 98241b9eb26SStefan Assmann the original IRQ line masked so that only the equivalent "boot 98341b9eb26SStefan Assmann IRQ" is delivered to the CPUs. The workaround also tells the 98441b9eb26SStefan Assmann kernel to set up the IRQ handler on the boot IRQ line. In this 98541b9eb26SStefan Assmann way only one interrupt is delivered to the kernel. Otherwise 98641b9eb26SStefan Assmann the spurious second interrupt may cause the kernel to bring 98741b9eb26SStefan Assmann down (vital) interrupt lines. 98841b9eb26SStefan Assmann 98941b9eb26SStefan Assmann Only affects "broken" chipsets. Interrupt sharing may be 99041b9eb26SStefan Assmann increased on these systems. 99141b9eb26SStefan Assmann 992506f1d07SSam Ravnborgconfig X86_MCE 993bab9bc65SAndi Kleen bool "Machine Check / overheating reporting" 994648ed940SChen, Gong select GENERIC_ALLOCATOR 995e57dbaf7SBorislav Petkov default y 996506f1d07SSam Ravnborg ---help--- 997bab9bc65SAndi Kleen Machine Check support allows the processor to notify the 998bab9bc65SAndi Kleen kernel if it detects a problem (e.g. overheating, data corruption). 999506f1d07SSam Ravnborg The action the kernel takes depends on the severity of the problem, 1000bab9bc65SAndi Kleen ranging from warning messages to halting the machine. 10014efc0670SAndi Kleen 1002506f1d07SSam Ravnborgconfig X86_MCE_INTEL 10033c2362e6SHarvey Harrison def_bool y 10043c2362e6SHarvey Harrison prompt "Intel MCE features" 1005c1ebf835SAndi Kleen depends on X86_MCE && X86_LOCAL_APIC 10068f9ca475SIngo Molnar ---help--- 1007506f1d07SSam Ravnborg Additional support for intel specific MCE features such as 1008506f1d07SSam Ravnborg the thermal monitor. 1009506f1d07SSam Ravnborg 1010506f1d07SSam Ravnborgconfig X86_MCE_AMD 10113c2362e6SHarvey Harrison def_bool y 10123c2362e6SHarvey Harrison prompt "AMD MCE features" 1013c1ebf835SAndi Kleen depends on X86_MCE && X86_LOCAL_APIC 10148f9ca475SIngo Molnar ---help--- 1015506f1d07SSam Ravnborg Additional support for AMD specific MCE features such as 1016506f1d07SSam Ravnborg the DRAM Error Threshold. 1017506f1d07SSam Ravnborg 10184efc0670SAndi Kleenconfig X86_ANCIENT_MCE 10196fc108a0SJan Beulich bool "Support for old Pentium 5 / WinChip machine checks" 1020c31d9633SAndi Kleen depends on X86_32 && X86_MCE 10214efc0670SAndi Kleen ---help--- 10224efc0670SAndi Kleen Include support for machine check handling on old Pentium 5 or WinChip 10235065a706SMasanari Iida systems. These typically need to be enabled explicitly on the command 10244efc0670SAndi Kleen line. 10254efc0670SAndi Kleen 1026b2762686SAndi Kleenconfig X86_MCE_THRESHOLD 1027b2762686SAndi Kleen depends on X86_MCE_AMD || X86_MCE_INTEL 10286fc108a0SJan Beulich def_bool y 1029b2762686SAndi Kleen 1030ea149b36SAndi Kleenconfig X86_MCE_INJECT 1031c1ebf835SAndi Kleen depends on X86_MCE 1032ea149b36SAndi Kleen tristate "Machine check injector support" 1033ea149b36SAndi Kleen ---help--- 1034ea149b36SAndi Kleen Provide support for injecting machine checks for testing purposes. 1035ea149b36SAndi Kleen If you don't know what a machine check is and you don't do kernel 1036ea149b36SAndi Kleen QA it is safe to say n. 1037ea149b36SAndi Kleen 10384efc0670SAndi Kleenconfig X86_THERMAL_VECTOR 10394efc0670SAndi Kleen def_bool y 10405bb38adcSAndi Kleen depends on X86_MCE_INTEL 10414efc0670SAndi Kleen 10425aef51c3SAndy Lutomirskiconfig X86_LEGACY_VM86 10431e642812SIngo Molnar bool "Legacy VM86 support" 10445aef51c3SAndy Lutomirski default n 1045506f1d07SSam Ravnborg depends on X86_32 10468f9ca475SIngo Molnar ---help--- 10475aef51c3SAndy Lutomirski This option allows user programs to put the CPU into V8086 10485aef51c3SAndy Lutomirski mode, which is an 80286-era approximation of 16-bit real mode. 10495aef51c3SAndy Lutomirski 10505aef51c3SAndy Lutomirski Some very old versions of X and/or vbetool require this option 10515aef51c3SAndy Lutomirski for user mode setting. Similarly, DOSEMU will use it if 10525aef51c3SAndy Lutomirski available to accelerate real mode DOS programs. However, any 10535aef51c3SAndy Lutomirski recent version of DOSEMU, X, or vbetool should be fully 10545aef51c3SAndy Lutomirski functional even without kernel VM86 support, as they will all 10551e642812SIngo Molnar fall back to software emulation. Nevertheless, if you are using 10561e642812SIngo Molnar a 16-bit DOS program where 16-bit performance matters, vm86 10571e642812SIngo Molnar mode might be faster than emulation and you might want to 10581e642812SIngo Molnar enable this option. 10595aef51c3SAndy Lutomirski 10601e642812SIngo Molnar Note that any app that works on a 64-bit kernel is unlikely to 10611e642812SIngo Molnar need this option, as 64-bit kernels don't, and can't, support 10621e642812SIngo Molnar V8086 mode. This option is also unrelated to 16-bit protected 10631e642812SIngo Molnar mode and is not needed to run most 16-bit programs under Wine. 10645aef51c3SAndy Lutomirski 10651e642812SIngo Molnar Enabling this option increases the complexity of the kernel 10661e642812SIngo Molnar and slows down exception handling a tiny bit. 10675aef51c3SAndy Lutomirski 10681e642812SIngo Molnar If unsure, say N here. 10695aef51c3SAndy Lutomirski 10705aef51c3SAndy Lutomirskiconfig VM86 10715aef51c3SAndy Lutomirski bool 10725aef51c3SAndy Lutomirski default X86_LEGACY_VM86 107334273f41SH. Peter Anvin 107434273f41SH. Peter Anvinconfig X86_16BIT 107534273f41SH. Peter Anvin bool "Enable support for 16-bit segments" if EXPERT 107634273f41SH. Peter Anvin default y 1077a5b9e5a2SAndy Lutomirski depends on MODIFY_LDT_SYSCALL 107834273f41SH. Peter Anvin ---help--- 107934273f41SH. Peter Anvin This option is required by programs like Wine to run 16-bit 108034273f41SH. Peter Anvin protected mode legacy code on x86 processors. Disabling 108134273f41SH. Peter Anvin this option saves about 300 bytes on i386, or around 6K text 108234273f41SH. Peter Anvin plus 16K runtime memory on x86-64, 108334273f41SH. Peter Anvin 108434273f41SH. Peter Anvinconfig X86_ESPFIX32 108534273f41SH. Peter Anvin def_bool y 108634273f41SH. Peter Anvin depends on X86_16BIT && X86_32 1087506f1d07SSam Ravnborg 1088197725deSH. Peter Anvinconfig X86_ESPFIX64 1089197725deSH. Peter Anvin def_bool y 109034273f41SH. Peter Anvin depends on X86_16BIT && X86_64 1091506f1d07SSam Ravnborg 10921ad83c85SAndy Lutomirskiconfig X86_VSYSCALL_EMULATION 10931ad83c85SAndy Lutomirski bool "Enable vsyscall emulation" if EXPERT 10941ad83c85SAndy Lutomirski default y 10951ad83c85SAndy Lutomirski depends on X86_64 10961ad83c85SAndy Lutomirski ---help--- 10971ad83c85SAndy Lutomirski This enables emulation of the legacy vsyscall page. Disabling 10981ad83c85SAndy Lutomirski it is roughly equivalent to booting with vsyscall=none, except 10991ad83c85SAndy Lutomirski that it will also disable the helpful warning if a program 11001ad83c85SAndy Lutomirski tries to use a vsyscall. With this option set to N, offending 11011ad83c85SAndy Lutomirski programs will just segfault, citing addresses of the form 11021ad83c85SAndy Lutomirski 0xffffffffff600?00. 11031ad83c85SAndy Lutomirski 11041ad83c85SAndy Lutomirski This option is required by many programs built before 2013, and 11051ad83c85SAndy Lutomirski care should be used even with newer programs if set to N. 11061ad83c85SAndy Lutomirski 11071ad83c85SAndy Lutomirski Disabling this option saves about 7K of kernel size and 11081ad83c85SAndy Lutomirski possibly 4K of additional runtime pagetable memory. 11091ad83c85SAndy Lutomirski 1110506f1d07SSam Ravnborgconfig TOSHIBA 1111506f1d07SSam Ravnborg tristate "Toshiba Laptop support" 1112506f1d07SSam Ravnborg depends on X86_32 1113506f1d07SSam Ravnborg ---help--- 1114506f1d07SSam Ravnborg This adds a driver to safely access the System Management Mode of 1115506f1d07SSam Ravnborg the CPU on Toshiba portables with a genuine Toshiba BIOS. It does 1116506f1d07SSam Ravnborg not work on models with a Phoenix BIOS. The System Management Mode 1117506f1d07SSam Ravnborg is used to set the BIOS and power saving options on Toshiba portables. 1118506f1d07SSam Ravnborg 1119506f1d07SSam Ravnborg For information on utilities to make use of this driver see the 1120506f1d07SSam Ravnborg Toshiba Linux utilities web site at: 1121506f1d07SSam Ravnborg <http://www.buzzard.org.uk/toshiba/>. 1122506f1d07SSam Ravnborg 1123506f1d07SSam Ravnborg Say Y if you intend to run this kernel on a Toshiba portable. 1124506f1d07SSam Ravnborg Say N otherwise. 1125506f1d07SSam Ravnborg 1126506f1d07SSam Ravnborgconfig I8K 1127039ae585SPali Rohár tristate "Dell i8k legacy laptop support" 1128949a9d70SJean Delvare select HWMON 1129039ae585SPali Rohár select SENSORS_DELL_SMM 1130506f1d07SSam Ravnborg ---help--- 1131039ae585SPali Rohár This option enables legacy /proc/i8k userspace interface in hwmon 1132039ae585SPali Rohár dell-smm-hwmon driver. Character file /proc/i8k reports bios version, 1133039ae585SPali Rohár temperature and allows controlling fan speeds of Dell laptops via 1134039ae585SPali Rohár System Management Mode. For old Dell laptops (like Dell Inspiron 8000) 1135039ae585SPali Rohár it reports also power and hotkey status. For fan speed control is 1136039ae585SPali Rohár needed userspace package i8kutils. 1137506f1d07SSam Ravnborg 1138039ae585SPali Rohár Say Y if you intend to run this kernel on old Dell laptops or want to 1139039ae585SPali Rohár use userspace package i8kutils. 1140506f1d07SSam Ravnborg Say N otherwise. 1141506f1d07SSam Ravnborg 1142506f1d07SSam Ravnborgconfig X86_REBOOTFIXUPS 11439ba16087SJan Beulich bool "Enable X86 board specific fixups for reboot" 11449ba16087SJan Beulich depends on X86_32 1145506f1d07SSam Ravnborg ---help--- 1146506f1d07SSam Ravnborg This enables chipset and/or board specific fixups to be done 1147506f1d07SSam Ravnborg in order to get reboot to work correctly. This is only needed on 1148506f1d07SSam Ravnborg some combinations of hardware and BIOS. The symptom, for which 1149506f1d07SSam Ravnborg this config is intended, is when reboot ends with a stalled/hung 1150506f1d07SSam Ravnborg system. 1151506f1d07SSam Ravnborg 1152506f1d07SSam Ravnborg Currently, the only fixup is for the Geode machines using 11535e3a77e9SFlorian Fainelli CS5530A and CS5536 chipsets and the RDC R-321x SoC. 1154506f1d07SSam Ravnborg 1155506f1d07SSam Ravnborg Say Y if you want to enable the fixup. Currently, it's safe to 1156506f1d07SSam Ravnborg enable this option even if you don't need it. 1157506f1d07SSam Ravnborg Say N otherwise. 1158506f1d07SSam Ravnborg 1159506f1d07SSam Ravnborgconfig MICROCODE 11609a2bc335SBorislav Petkov bool "CPU microcode loading support" 11619a2bc335SBorislav Petkov default y 116280030e3dSBorislav Petkov depends on CPU_SUP_AMD || CPU_SUP_INTEL 1163fe055896SBorislav Petkov depends on BLK_DEV_INITRD 1164506f1d07SSam Ravnborg select FW_LOADER 1165506f1d07SSam Ravnborg ---help--- 1166e43f6e67SBorislav Petkov 1167506f1d07SSam Ravnborg If you say Y here, you will be able to update the microcode on 116880cc9f10SPeter Oruba certain Intel and AMD processors. The Intel support is for the 1169e43f6e67SBorislav Petkov IA32 family, e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, 1170e43f6e67SBorislav Petkov Xeon etc. The AMD support is for families 0x10 and later. You will 1171e43f6e67SBorislav Petkov obviously need the actual microcode binary data itself which is not 1172e43f6e67SBorislav Petkov shipped with the Linux kernel. 1173506f1d07SSam Ravnborg 11748d86f390SPeter Oruba This option selects the general module only, you need to select 11758d86f390SPeter Oruba at least one vendor specific module as well. 1176506f1d07SSam Ravnborg 1177e43f6e67SBorislav Petkov To compile this driver as a module, choose M here: the module 1178e43f6e67SBorislav Petkov will be called microcode. 1179506f1d07SSam Ravnborg 11808d86f390SPeter Orubaconfig MICROCODE_INTEL 1181e43f6e67SBorislav Petkov bool "Intel microcode loading support" 11828d86f390SPeter Oruba depends on MICROCODE 11838d86f390SPeter Oruba default MICROCODE 11848d86f390SPeter Oruba select FW_LOADER 11858f9ca475SIngo Molnar ---help--- 11868d86f390SPeter Oruba This options enables microcode patch loading support for Intel 11878d86f390SPeter Oruba processors. 11888d86f390SPeter Oruba 1189b8989db9SAlan For the current Intel microcode data package go to 1190b8989db9SAlan <https://downloadcenter.intel.com> and search for 1191b8989db9SAlan 'Linux Processor Microcode Data File'. 11928d86f390SPeter Oruba 119380cc9f10SPeter Orubaconfig MICROCODE_AMD 1194e43f6e67SBorislav Petkov bool "AMD microcode loading support" 119580cc9f10SPeter Oruba depends on MICROCODE 119680cc9f10SPeter Oruba select FW_LOADER 11978f9ca475SIngo Molnar ---help--- 119880cc9f10SPeter Oruba If you select this option, microcode patch loading support for AMD 119980cc9f10SPeter Oruba processors will be enabled. 120080cc9f10SPeter Oruba 1201506f1d07SSam Ravnborgconfig MICROCODE_OLD_INTERFACE 12023c2362e6SHarvey Harrison def_bool y 1203506f1d07SSam Ravnborg depends on MICROCODE 1204506f1d07SSam Ravnborg 1205506f1d07SSam Ravnborgconfig X86_MSR 1206506f1d07SSam Ravnborg tristate "/dev/cpu/*/msr - Model-specific register support" 12078f9ca475SIngo Molnar ---help--- 1208506f1d07SSam Ravnborg This device gives privileged processes access to the x86 1209506f1d07SSam Ravnborg Model-Specific Registers (MSRs). It is a character device with 1210506f1d07SSam Ravnborg major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. 1211506f1d07SSam Ravnborg MSR accesses are directed to a specific CPU on multi-processor 1212506f1d07SSam Ravnborg systems. 1213506f1d07SSam Ravnborg 1214506f1d07SSam Ravnborgconfig X86_CPUID 1215506f1d07SSam Ravnborg tristate "/dev/cpu/*/cpuid - CPU information support" 12168f9ca475SIngo Molnar ---help--- 1217506f1d07SSam Ravnborg This device gives processes access to the x86 CPUID instruction to 1218506f1d07SSam Ravnborg be executed on a specific processor. It is a character device 1219506f1d07SSam Ravnborg with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to 1220506f1d07SSam Ravnborg /dev/cpu/31/cpuid. 1221506f1d07SSam Ravnborg 1222506f1d07SSam Ravnborgchoice 1223506f1d07SSam Ravnborg prompt "High Memory Support" 12246fc108a0SJan Beulich default HIGHMEM4G 1225506f1d07SSam Ravnborg depends on X86_32 1226506f1d07SSam Ravnborg 1227506f1d07SSam Ravnborgconfig NOHIGHMEM 1228506f1d07SSam Ravnborg bool "off" 1229506f1d07SSam Ravnborg ---help--- 1230506f1d07SSam Ravnborg Linux can use up to 64 Gigabytes of physical memory on x86 systems. 1231506f1d07SSam Ravnborg However, the address space of 32-bit x86 processors is only 4 1232506f1d07SSam Ravnborg Gigabytes large. That means that, if you have a large amount of 1233506f1d07SSam Ravnborg physical memory, not all of it can be "permanently mapped" by the 1234506f1d07SSam Ravnborg kernel. The physical memory that's not permanently mapped is called 1235506f1d07SSam Ravnborg "high memory". 1236506f1d07SSam Ravnborg 1237506f1d07SSam Ravnborg If you are compiling a kernel which will never run on a machine with 1238506f1d07SSam Ravnborg more than 1 Gigabyte total physical RAM, answer "off" here (default 1239506f1d07SSam Ravnborg choice and suitable for most users). This will result in a "3GB/1GB" 1240506f1d07SSam Ravnborg split: 3GB are mapped so that each process sees a 3GB virtual memory 1241506f1d07SSam Ravnborg space and the remaining part of the 4GB virtual memory space is used 1242506f1d07SSam Ravnborg by the kernel to permanently map as much physical memory as 1243506f1d07SSam Ravnborg possible. 1244506f1d07SSam Ravnborg 1245506f1d07SSam Ravnborg If the machine has between 1 and 4 Gigabytes physical RAM, then 1246506f1d07SSam Ravnborg answer "4GB" here. 1247506f1d07SSam Ravnborg 1248506f1d07SSam Ravnborg If more than 4 Gigabytes is used then answer "64GB" here. This 1249506f1d07SSam Ravnborg selection turns Intel PAE (Physical Address Extension) mode on. 1250506f1d07SSam Ravnborg PAE implements 3-level paging on IA32 processors. PAE is fully 1251506f1d07SSam Ravnborg supported by Linux, PAE mode is implemented on all recent Intel 1252506f1d07SSam Ravnborg processors (Pentium Pro and better). NOTE: If you say "64GB" here, 1253506f1d07SSam Ravnborg then the kernel will not boot on CPUs that don't support PAE! 1254506f1d07SSam Ravnborg 1255506f1d07SSam Ravnborg The actual amount of total physical memory will either be 1256506f1d07SSam Ravnborg auto detected or can be forced by using a kernel command line option 1257506f1d07SSam Ravnborg such as "mem=256M". (Try "man bootparam" or see the documentation of 1258506f1d07SSam Ravnborg your boot loader (lilo or loadlin) about how to pass options to the 1259506f1d07SSam Ravnborg kernel at boot time.) 1260506f1d07SSam Ravnborg 1261506f1d07SSam Ravnborg If unsure, say "off". 1262506f1d07SSam Ravnborg 1263506f1d07SSam Ravnborgconfig HIGHMEM4G 1264506f1d07SSam Ravnborg bool "4GB" 12658f9ca475SIngo Molnar ---help--- 1266506f1d07SSam Ravnborg Select this if you have a 32-bit processor and between 1 and 4 1267506f1d07SSam Ravnborg gigabytes of physical RAM. 1268506f1d07SSam Ravnborg 1269506f1d07SSam Ravnborgconfig HIGHMEM64G 1270506f1d07SSam Ravnborg bool "64GB" 1271eb068e78SH. Peter Anvin depends on !M486 1272506f1d07SSam Ravnborg select X86_PAE 12738f9ca475SIngo Molnar ---help--- 1274506f1d07SSam Ravnborg Select this if you have a 32-bit processor and more than 4 1275506f1d07SSam Ravnborg gigabytes of physical RAM. 1276506f1d07SSam Ravnborg 1277506f1d07SSam Ravnborgendchoice 1278506f1d07SSam Ravnborg 1279506f1d07SSam Ravnborgchoice 12806a108a14SDavid Rientjes prompt "Memory split" if EXPERT 1281506f1d07SSam Ravnborg default VMSPLIT_3G 1282506f1d07SSam Ravnborg depends on X86_32 12838f9ca475SIngo Molnar ---help--- 1284506f1d07SSam Ravnborg Select the desired split between kernel and user memory. 1285506f1d07SSam Ravnborg 1286506f1d07SSam Ravnborg If the address range available to the kernel is less than the 1287506f1d07SSam Ravnborg physical memory installed, the remaining memory will be available 1288506f1d07SSam Ravnborg as "high memory". Accessing high memory is a little more costly 1289506f1d07SSam Ravnborg than low memory, as it needs to be mapped into the kernel first. 1290506f1d07SSam Ravnborg Note that increasing the kernel address space limits the range 1291506f1d07SSam Ravnborg available to user programs, making the address space there 1292506f1d07SSam Ravnborg tighter. Selecting anything other than the default 3G/1G split 1293506f1d07SSam Ravnborg will also likely make your kernel incompatible with binary-only 1294506f1d07SSam Ravnborg kernel modules. 1295506f1d07SSam Ravnborg 1296506f1d07SSam Ravnborg If you are not absolutely sure what you are doing, leave this 1297506f1d07SSam Ravnborg option alone! 1298506f1d07SSam Ravnborg 1299506f1d07SSam Ravnborg config VMSPLIT_3G 1300506f1d07SSam Ravnborg bool "3G/1G user/kernel split" 1301506f1d07SSam Ravnborg config VMSPLIT_3G_OPT 1302506f1d07SSam Ravnborg depends on !X86_PAE 1303506f1d07SSam Ravnborg bool "3G/1G user/kernel split (for full 1G low memory)" 1304506f1d07SSam Ravnborg config VMSPLIT_2G 1305506f1d07SSam Ravnborg bool "2G/2G user/kernel split" 1306506f1d07SSam Ravnborg config VMSPLIT_2G_OPT 1307506f1d07SSam Ravnborg depends on !X86_PAE 1308506f1d07SSam Ravnborg bool "2G/2G user/kernel split (for full 2G low memory)" 1309506f1d07SSam Ravnborg config VMSPLIT_1G 1310506f1d07SSam Ravnborg bool "1G/3G user/kernel split" 1311506f1d07SSam Ravnborgendchoice 1312506f1d07SSam Ravnborg 1313506f1d07SSam Ravnborgconfig PAGE_OFFSET 1314506f1d07SSam Ravnborg hex 1315506f1d07SSam Ravnborg default 0xB0000000 if VMSPLIT_3G_OPT 1316506f1d07SSam Ravnborg default 0x80000000 if VMSPLIT_2G 1317506f1d07SSam Ravnborg default 0x78000000 if VMSPLIT_2G_OPT 1318506f1d07SSam Ravnborg default 0x40000000 if VMSPLIT_1G 1319506f1d07SSam Ravnborg default 0xC0000000 1320506f1d07SSam Ravnborg depends on X86_32 1321506f1d07SSam Ravnborg 1322506f1d07SSam Ravnborgconfig HIGHMEM 13233c2362e6SHarvey Harrison def_bool y 1324506f1d07SSam Ravnborg depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) 1325506f1d07SSam Ravnborg 1326506f1d07SSam Ravnborgconfig X86_PAE 13279ba16087SJan Beulich bool "PAE (Physical Address Extension) Support" 1328506f1d07SSam Ravnborg depends on X86_32 && !HIGHMEM4G 13299d99c712SChristian Melki select SWIOTLB 13308f9ca475SIngo Molnar ---help--- 1331506f1d07SSam Ravnborg PAE is required for NX support, and furthermore enables 1332506f1d07SSam Ravnborg larger swapspace support for non-overcommit purposes. It 1333506f1d07SSam Ravnborg has the cost of more pagetable lookup overhead, and also 1334506f1d07SSam Ravnborg consumes more pagetable space per process. 1335506f1d07SSam Ravnborg 1336600715dcSJeremy Fitzhardingeconfig ARCH_PHYS_ADDR_T_64BIT 13373120e25eSJan Beulich def_bool y 13383120e25eSJan Beulich depends on X86_64 || X86_PAE 1339600715dcSJeremy Fitzhardinge 134066f2b061SFUJITA Tomonoriconfig ARCH_DMA_ADDR_T_64BIT 13413120e25eSJan Beulich def_bool y 13423120e25eSJan Beulich depends on X86_64 || HIGHMEM64G 134366f2b061SFUJITA Tomonori 134410971ab2SIngo Molnarconfig X86_DIRECT_GBPAGES 1345e5008abeSLuis R. Rodriguez def_bool y 1346e5008abeSLuis R. Rodriguez depends on X86_64 && !DEBUG_PAGEALLOC && !KMEMCHECK 13478f9ca475SIngo Molnar ---help--- 134810971ab2SIngo Molnar Certain kernel features effectively disable kernel 134910971ab2SIngo Molnar linear 1 GB mappings (even if the CPU otherwise 135010971ab2SIngo Molnar supports them), so don't confuse the user by printing 135110971ab2SIngo Molnar that we have them enabled. 13529e899816SNick Piggin 1353506f1d07SSam Ravnborg# Common NUMA Features 1354506f1d07SSam Ravnborgconfig NUMA 1355fd51b2d7SKOSAKI Motohiro bool "Numa Memory Allocation and Scheduler Support" 1356506f1d07SSam Ravnborg depends on SMP 1357b5660ba7SH. Peter Anvin depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP) 1358b5660ba7SH. Peter Anvin default y if X86_BIGSMP 13598f9ca475SIngo Molnar ---help--- 1360506f1d07SSam Ravnborg Enable NUMA (Non Uniform Memory Access) support. 1361fd51b2d7SKOSAKI Motohiro 1362506f1d07SSam Ravnborg The kernel will try to allocate memory used by a CPU on the 1363506f1d07SSam Ravnborg local memory controller of the CPU and add some more 1364506f1d07SSam Ravnborg NUMA awareness to the kernel. 1365506f1d07SSam Ravnborg 1366c280ea5eSIngo Molnar For 64-bit this is recommended if the system is Intel Core i7 1367fd51b2d7SKOSAKI Motohiro (or later), AMD Opteron, or EM64T NUMA. 1368fd51b2d7SKOSAKI Motohiro 1369b5660ba7SH. Peter Anvin For 32-bit this is only needed if you boot a 32-bit 13707cf6c945SDavid Rientjes kernel on a 64-bit NUMA platform. 1371fd51b2d7SKOSAKI Motohiro 1372fd51b2d7SKOSAKI Motohiro Otherwise, you should say N. 1373506f1d07SSam Ravnborg 1374eec1d4faSHans Rosenfeldconfig AMD_NUMA 13753c2362e6SHarvey Harrison def_bool y 13763c2362e6SHarvey Harrison prompt "Old style AMD Opteron NUMA detection" 13775da0ef9aSTejun Heo depends on X86_64 && NUMA && PCI 13788f9ca475SIngo Molnar ---help--- 1379eec1d4faSHans Rosenfeld Enable AMD NUMA node topology detection. You should say Y here if 1380eec1d4faSHans Rosenfeld you have a multi processor AMD system. This uses an old method to 1381eec1d4faSHans Rosenfeld read the NUMA configuration directly from the builtin Northbridge 1382eec1d4faSHans Rosenfeld of Opteron. It is recommended to use X86_64_ACPI_NUMA instead, 1383eec1d4faSHans Rosenfeld which also takes priority if both are compiled in. 1384506f1d07SSam Ravnborg 1385506f1d07SSam Ravnborgconfig X86_64_ACPI_NUMA 13863c2362e6SHarvey Harrison def_bool y 13873c2362e6SHarvey Harrison prompt "ACPI NUMA detection" 1388506f1d07SSam Ravnborg depends on X86_64 && NUMA && ACPI && PCI 1389506f1d07SSam Ravnborg select ACPI_NUMA 13908f9ca475SIngo Molnar ---help--- 1391506f1d07SSam Ravnborg Enable ACPI SRAT based node topology detection. 1392506f1d07SSam Ravnborg 13936ec6e0d9SSuresh Siddha# Some NUMA nodes have memory ranges that span 13946ec6e0d9SSuresh Siddha# other nodes. Even though a pfn is valid and 13956ec6e0d9SSuresh Siddha# between a node's start and end pfns, it may not 13966ec6e0d9SSuresh Siddha# reside on that node. See memmap_init_zone() 13976ec6e0d9SSuresh Siddha# for details. 13986ec6e0d9SSuresh Siddhaconfig NODES_SPAN_OTHER_NODES 13996ec6e0d9SSuresh Siddha def_bool y 14006ec6e0d9SSuresh Siddha depends on X86_64_ACPI_NUMA 14016ec6e0d9SSuresh Siddha 1402506f1d07SSam Ravnborgconfig NUMA_EMU 1403506f1d07SSam Ravnborg bool "NUMA emulation" 14041b7e03efSTejun Heo depends on NUMA 14058f9ca475SIngo Molnar ---help--- 1406506f1d07SSam Ravnborg Enable NUMA emulation. A flat machine will be split 1407506f1d07SSam Ravnborg into virtual nodes when booted with "numa=fake=N", where N is the 1408506f1d07SSam Ravnborg number of nodes. This is only useful for debugging. 1409506f1d07SSam Ravnborg 1410506f1d07SSam Ravnborgconfig NODES_SHIFT 1411d25e26b6SLinus Torvalds int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP 141251591e31SDavid Rientjes range 1 10 141351591e31SDavid Rientjes default "10" if MAXSMP 1414506f1d07SSam Ravnborg default "6" if X86_64 1415506f1d07SSam Ravnborg default "3" 1416506f1d07SSam Ravnborg depends on NEED_MULTIPLE_NODES 14178f9ca475SIngo Molnar ---help--- 14181184dc2fSMike Travis Specify the maximum number of NUMA Nodes available on the target 1419692105b8SMatt LaPlante system. Increases memory reserved to accommodate various tables. 1420506f1d07SSam Ravnborg 1421506f1d07SSam Ravnborgconfig ARCH_HAVE_MEMORY_PRESENT 14223c2362e6SHarvey Harrison def_bool y 1423506f1d07SSam Ravnborg depends on X86_32 && DISCONTIGMEM 1424506f1d07SSam Ravnborg 1425506f1d07SSam Ravnborgconfig NEED_NODE_MEMMAP_SIZE 14263c2362e6SHarvey Harrison def_bool y 1427506f1d07SSam Ravnborg depends on X86_32 && (DISCONTIGMEM || SPARSEMEM) 1428506f1d07SSam Ravnborg 1429506f1d07SSam Ravnborgconfig ARCH_FLATMEM_ENABLE 1430506f1d07SSam Ravnborg def_bool y 14313b16651fSTejun Heo depends on X86_32 && !NUMA 1432506f1d07SSam Ravnborg 1433506f1d07SSam Ravnborgconfig ARCH_DISCONTIGMEM_ENABLE 1434506f1d07SSam Ravnborg def_bool y 1435b263295dSChristoph Lameter depends on NUMA && X86_32 1436506f1d07SSam Ravnborg 1437506f1d07SSam Ravnborgconfig ARCH_DISCONTIGMEM_DEFAULT 1438506f1d07SSam Ravnborg def_bool y 1439b263295dSChristoph Lameter depends on NUMA && X86_32 1440b263295dSChristoph Lameter 1441506f1d07SSam Ravnborgconfig ARCH_SPARSEMEM_ENABLE 1442506f1d07SSam Ravnborg def_bool y 14436ea30386SKees Cook depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD 1444506f1d07SSam Ravnborg select SPARSEMEM_STATIC if X86_32 1445506f1d07SSam Ravnborg select SPARSEMEM_VMEMMAP_ENABLE if X86_64 1446506f1d07SSam Ravnborg 14473b16651fSTejun Heoconfig ARCH_SPARSEMEM_DEFAULT 14483b16651fSTejun Heo def_bool y 14493b16651fSTejun Heo depends on X86_64 14503b16651fSTejun Heo 1451506f1d07SSam Ravnborgconfig ARCH_SELECT_MEMORY_MODEL 1452506f1d07SSam Ravnborg def_bool y 1453b263295dSChristoph Lameter depends on ARCH_SPARSEMEM_ENABLE 1454506f1d07SSam Ravnborg 1455506f1d07SSam Ravnborgconfig ARCH_MEMORY_PROBE 1456a0842b70SToshi Kani bool "Enable sysfs memory/probe interface" 14573120e25eSJan Beulich depends on X86_64 && MEMORY_HOTPLUG 1458a0842b70SToshi Kani help 1459a0842b70SToshi Kani This option enables a sysfs memory/probe interface for testing. 1460a0842b70SToshi Kani See Documentation/memory-hotplug.txt for more information. 1461a0842b70SToshi Kani If you are unsure how to answer this question, answer N. 1462506f1d07SSam Ravnborg 14633b16651fSTejun Heoconfig ARCH_PROC_KCORE_TEXT 14643b16651fSTejun Heo def_bool y 14653b16651fSTejun Heo depends on X86_64 && PROC_KCORE 14663b16651fSTejun Heo 1467a29815a3SAvi Kivityconfig ILLEGAL_POINTER_VALUE 1468a29815a3SAvi Kivity hex 1469a29815a3SAvi Kivity default 0 if X86_32 1470a29815a3SAvi Kivity default 0xdead000000000000 if X86_64 1471a29815a3SAvi Kivity 1472506f1d07SSam Ravnborgsource "mm/Kconfig" 1473506f1d07SSam Ravnborg 14747a67832cSDan Williamsconfig X86_PMEM_LEGACY_DEVICE 14757a67832cSDan Williams bool 14767a67832cSDan Williams 1477ec776ef6SChristoph Hellwigconfig X86_PMEM_LEGACY 14787a67832cSDan Williams tristate "Support non-standard NVDIMMs and ADR protected memory" 14799f53f9faSDan Williams depends on PHYS_ADDR_T_64BIT 14809f53f9faSDan Williams depends on BLK_DEV 14817a67832cSDan Williams select X86_PMEM_LEGACY_DEVICE 14829f53f9faSDan Williams select LIBNVDIMM 1483ec776ef6SChristoph Hellwig help 1484ec776ef6SChristoph Hellwig Treat memory marked using the non-standard e820 type of 12 as used 1485ec776ef6SChristoph Hellwig by the Intel Sandy Bridge-EP reference BIOS as protected memory. 1486ec776ef6SChristoph Hellwig The kernel will offer these regions to the 'pmem' driver so 1487ec776ef6SChristoph Hellwig they can be used for persistent storage. 1488ec776ef6SChristoph Hellwig 1489ec776ef6SChristoph Hellwig Say Y if unsure. 1490ec776ef6SChristoph Hellwig 1491506f1d07SSam Ravnborgconfig HIGHPTE 1492506f1d07SSam Ravnborg bool "Allocate 3rd-level pagetables from highmem" 14936fc108a0SJan Beulich depends on HIGHMEM 14948f9ca475SIngo Molnar ---help--- 1495506f1d07SSam Ravnborg The VM uses one page table entry for each page of physical memory. 1496506f1d07SSam Ravnborg For systems with a lot of RAM, this can be wasteful of precious 1497506f1d07SSam Ravnborg low memory. Setting this option will put user-space page table 1498506f1d07SSam Ravnborg entries in high memory. 1499506f1d07SSam Ravnborg 15009f077871SJeremy Fitzhardingeconfig X86_CHECK_BIOS_CORRUPTION 15019f077871SJeremy Fitzhardinge bool "Check for low memory corruption" 15028f9ca475SIngo Molnar ---help--- 15039f077871SJeremy Fitzhardinge Periodically check for memory corruption in low memory, which 15049f077871SJeremy Fitzhardinge is suspected to be caused by BIOS. Even when enabled in the 15059f077871SJeremy Fitzhardinge configuration, it is disabled at runtime. Enable it by 15069f077871SJeremy Fitzhardinge setting "memory_corruption_check=1" on the kernel command 15079f077871SJeremy Fitzhardinge line. By default it scans the low 64k of memory every 60 15089f077871SJeremy Fitzhardinge seconds; see the memory_corruption_check_size and 15099f077871SJeremy Fitzhardinge memory_corruption_check_period parameters in 15109f077871SJeremy Fitzhardinge Documentation/kernel-parameters.txt to adjust this. 15119f077871SJeremy Fitzhardinge 15129f077871SJeremy Fitzhardinge When enabled with the default parameters, this option has 15139f077871SJeremy Fitzhardinge almost no overhead, as it reserves a relatively small amount 15149f077871SJeremy Fitzhardinge of memory and scans it infrequently. It both detects corruption 15159f077871SJeremy Fitzhardinge and prevents it from affecting the running system. 15169f077871SJeremy Fitzhardinge 15179f077871SJeremy Fitzhardinge It is, however, intended as a diagnostic tool; if repeatable 15189f077871SJeremy Fitzhardinge BIOS-originated corruption always affects the same memory, 15199f077871SJeremy Fitzhardinge you can use memmap= to prevent the kernel from using that 15209f077871SJeremy Fitzhardinge memory. 15219f077871SJeremy Fitzhardinge 1522c885df50SJeremy Fitzhardingeconfig X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK 1523c885df50SJeremy Fitzhardinge bool "Set the default setting of memory_corruption_check" 1524c885df50SJeremy Fitzhardinge depends on X86_CHECK_BIOS_CORRUPTION 1525c885df50SJeremy Fitzhardinge default y 15268f9ca475SIngo Molnar ---help--- 1527c885df50SJeremy Fitzhardinge Set whether the default state of memory_corruption_check is 1528c885df50SJeremy Fitzhardinge on or off. 1529c885df50SJeremy Fitzhardinge 15309ea77bdbSH. Peter Anvinconfig X86_RESERVE_LOW 1531d0cd7425SH. Peter Anvin int "Amount of low memory, in kilobytes, to reserve for the BIOS" 1532d0cd7425SH. Peter Anvin default 64 1533d0cd7425SH. Peter Anvin range 4 640 15348f9ca475SIngo Molnar ---help--- 1535d0cd7425SH. Peter Anvin Specify the amount of low memory to reserve for the BIOS. 1536fc381519SIngo Molnar 1537d0cd7425SH. Peter Anvin The first page contains BIOS data structures that the kernel 1538d0cd7425SH. Peter Anvin must not use, so that page must always be reserved. 1539fc381519SIngo Molnar 1540d0cd7425SH. Peter Anvin By default we reserve the first 64K of physical RAM, as a 1541d0cd7425SH. Peter Anvin number of BIOSes are known to corrupt that memory range 1542d0cd7425SH. Peter Anvin during events such as suspend/resume or monitor cable 1543d0cd7425SH. Peter Anvin insertion, so it must not be used by the kernel. 1544fc381519SIngo Molnar 1545d0cd7425SH. Peter Anvin You can set this to 4 if you are absolutely sure that you 1546d0cd7425SH. Peter Anvin trust the BIOS to get all its memory reservations and usages 1547d0cd7425SH. Peter Anvin right. If you know your BIOS have problems beyond the 1548d0cd7425SH. Peter Anvin default 64K area, you can set this to 640 to avoid using the 1549d0cd7425SH. Peter Anvin entire low memory range. 1550d0cd7425SH. Peter Anvin 1551d0cd7425SH. Peter Anvin If you have doubts about the BIOS (e.g. suspend/resume does 1552d0cd7425SH. Peter Anvin not work or there's kernel crashes after certain hardware 1553d0cd7425SH. Peter Anvin hotplug events) then you might want to enable 1554d0cd7425SH. Peter Anvin X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check 1555d0cd7425SH. Peter Anvin typical corruption patterns. 1556d0cd7425SH. Peter Anvin 1557d0cd7425SH. Peter Anvin Leave this to the default value of 64 if you are unsure. 1558fc381519SIngo Molnar 1559506f1d07SSam Ravnborgconfig MATH_EMULATION 1560506f1d07SSam Ravnborg bool 1561a5b9e5a2SAndy Lutomirski depends on MODIFY_LDT_SYSCALL 1562506f1d07SSam Ravnborg prompt "Math emulation" if X86_32 1563506f1d07SSam Ravnborg ---help--- 1564506f1d07SSam Ravnborg Linux can emulate a math coprocessor (used for floating point 1565506f1d07SSam Ravnborg operations) if you don't have one. 486DX and Pentium processors have 1566506f1d07SSam Ravnborg a math coprocessor built in, 486SX and 386 do not, unless you added 1567506f1d07SSam Ravnborg a 487DX or 387, respectively. (The messages during boot time can 1568506f1d07SSam Ravnborg give you some hints here ["man dmesg"].) Everyone needs either a 1569506f1d07SSam Ravnborg coprocessor or this emulation. 1570506f1d07SSam Ravnborg 1571506f1d07SSam Ravnborg If you don't have a math coprocessor, you need to say Y here; if you 1572506f1d07SSam Ravnborg say Y here even though you have a coprocessor, the coprocessor will 1573506f1d07SSam Ravnborg be used nevertheless. (This behavior can be changed with the kernel 1574506f1d07SSam Ravnborg command line option "no387", which comes handy if your coprocessor 1575506f1d07SSam Ravnborg is broken. Try "man bootparam" or see the documentation of your boot 1576506f1d07SSam Ravnborg loader (lilo or loadlin) about how to pass options to the kernel at 1577506f1d07SSam Ravnborg boot time.) This means that it is a good idea to say Y here if you 1578506f1d07SSam Ravnborg intend to use this kernel on different machines. 1579506f1d07SSam Ravnborg 1580506f1d07SSam Ravnborg More information about the internals of the Linux math coprocessor 1581506f1d07SSam Ravnborg emulation can be found in <file:arch/x86/math-emu/README>. 1582506f1d07SSam Ravnborg 1583506f1d07SSam Ravnborg If you are not sure, say Y; apart from resulting in a 66 KB bigger 1584506f1d07SSam Ravnborg kernel, it won't hurt. 1585506f1d07SSam Ravnborg 1586506f1d07SSam Ravnborgconfig MTRR 15876fc108a0SJan Beulich def_bool y 15886a108a14SDavid Rientjes prompt "MTRR (Memory Type Range Register) support" if EXPERT 1589506f1d07SSam Ravnborg ---help--- 1590506f1d07SSam Ravnborg On Intel P6 family processors (Pentium Pro, Pentium II and later) 1591506f1d07SSam Ravnborg the Memory Type Range Registers (MTRRs) may be used to control 1592506f1d07SSam Ravnborg processor access to memory ranges. This is most useful if you have 1593506f1d07SSam Ravnborg a video (VGA) card on a PCI or AGP bus. Enabling write-combining 1594506f1d07SSam Ravnborg allows bus write transfers to be combined into a larger transfer 1595506f1d07SSam Ravnborg before bursting over the PCI/AGP bus. This can increase performance 1596506f1d07SSam Ravnborg of image write operations 2.5 times or more. Saying Y here creates a 1597506f1d07SSam Ravnborg /proc/mtrr file which may be used to manipulate your processor's 1598506f1d07SSam Ravnborg MTRRs. Typically the X server should use this. 1599506f1d07SSam Ravnborg 1600506f1d07SSam Ravnborg This code has a reasonably generic interface so that similar 1601506f1d07SSam Ravnborg control registers on other processors can be easily supported 1602506f1d07SSam Ravnborg as well: 1603506f1d07SSam Ravnborg 1604506f1d07SSam Ravnborg The Cyrix 6x86, 6x86MX and M II processors have Address Range 1605506f1d07SSam Ravnborg Registers (ARRs) which provide a similar functionality to MTRRs. For 1606506f1d07SSam Ravnborg these, the ARRs are used to emulate the MTRRs. 1607506f1d07SSam Ravnborg The AMD K6-2 (stepping 8 and above) and K6-3 processors have two 1608506f1d07SSam Ravnborg MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing 1609506f1d07SSam Ravnborg write-combining. All of these processors are supported by this code 1610506f1d07SSam Ravnborg and it makes sense to say Y here if you have one of them. 1611506f1d07SSam Ravnborg 1612506f1d07SSam Ravnborg Saying Y here also fixes a problem with buggy SMP BIOSes which only 1613506f1d07SSam Ravnborg set the MTRRs for the boot CPU and not for the secondary CPUs. This 1614506f1d07SSam Ravnborg can lead to all sorts of problems, so it's good to say Y here. 1615506f1d07SSam Ravnborg 1616506f1d07SSam Ravnborg You can safely say Y even if your machine doesn't have MTRRs, you'll 1617506f1d07SSam Ravnborg just add about 9 KB to your kernel. 1618506f1d07SSam Ravnborg 16197225e751SRandy Dunlap See <file:Documentation/x86/mtrr.txt> for more information. 1620506f1d07SSam Ravnborg 162195ffa243SYinghai Luconfig MTRR_SANITIZER 16222ffb3501SYinghai Lu def_bool y 162395ffa243SYinghai Lu prompt "MTRR cleanup support" 162495ffa243SYinghai Lu depends on MTRR 16258f9ca475SIngo Molnar ---help--- 1626aba3728cSThomas Gleixner Convert MTRR layout from continuous to discrete, so X drivers can 1627aba3728cSThomas Gleixner add writeback entries. 162895ffa243SYinghai Lu 1629aba3728cSThomas Gleixner Can be disabled with disable_mtrr_cleanup on the kernel command line. 1630692105b8SMatt LaPlante The largest mtrr entry size for a continuous block can be set with 1631aba3728cSThomas Gleixner mtrr_chunk_size. 163295ffa243SYinghai Lu 16332ffb3501SYinghai Lu If unsure, say Y. 163495ffa243SYinghai Lu 163595ffa243SYinghai Luconfig MTRR_SANITIZER_ENABLE_DEFAULT 1636f5098d62SYinghai Lu int "MTRR cleanup enable value (0-1)" 1637f5098d62SYinghai Lu range 0 1 1638f5098d62SYinghai Lu default "0" 163995ffa243SYinghai Lu depends on MTRR_SANITIZER 16408f9ca475SIngo Molnar ---help--- 1641f5098d62SYinghai Lu Enable mtrr cleanup default value 164295ffa243SYinghai Lu 164312031a62SYinghai Luconfig MTRR_SANITIZER_SPARE_REG_NR_DEFAULT 164412031a62SYinghai Lu int "MTRR cleanup spare reg num (0-7)" 164512031a62SYinghai Lu range 0 7 164612031a62SYinghai Lu default "1" 164712031a62SYinghai Lu depends on MTRR_SANITIZER 16488f9ca475SIngo Molnar ---help--- 164912031a62SYinghai Lu mtrr cleanup spare entries default, it can be changed via 1650aba3728cSThomas Gleixner mtrr_spare_reg_nr=N on the kernel command line. 165112031a62SYinghai Lu 16522e5d9c85Svenkatesh.pallipadi@intel.comconfig X86_PAT 16536fc108a0SJan Beulich def_bool y 16546a108a14SDavid Rientjes prompt "x86 PAT support" if EXPERT 16552a8a2719SIngo Molnar depends on MTRR 16568f9ca475SIngo Molnar ---help--- 16572e5d9c85Svenkatesh.pallipadi@intel.com Use PAT attributes to setup page level cache control. 1658042b78e4SVenki Pallipadi 16592e5d9c85Svenkatesh.pallipadi@intel.com PATs are the modern equivalents of MTRRs and are much more 16602e5d9c85Svenkatesh.pallipadi@intel.com flexible than MTRRs. 16612e5d9c85Svenkatesh.pallipadi@intel.com 16622e5d9c85Svenkatesh.pallipadi@intel.com Say N here if you see bootup problems (boot crash, boot hang, 1663042b78e4SVenki Pallipadi spontaneous reboots) or a non-working video driver. 16642e5d9c85Svenkatesh.pallipadi@intel.com 16652e5d9c85Svenkatesh.pallipadi@intel.com If unsure, say Y. 16662e5d9c85Svenkatesh.pallipadi@intel.com 166746cf98cdSVenkatesh Pallipadiconfig ARCH_USES_PG_UNCACHED 166846cf98cdSVenkatesh Pallipadi def_bool y 166946cf98cdSVenkatesh Pallipadi depends on X86_PAT 167046cf98cdSVenkatesh Pallipadi 1671628c6246SH. Peter Anvinconfig ARCH_RANDOM 1672628c6246SH. Peter Anvin def_bool y 1673628c6246SH. Peter Anvin prompt "x86 architectural random number generator" if EXPERT 1674628c6246SH. Peter Anvin ---help--- 1675628c6246SH. Peter Anvin Enable the x86 architectural RDRAND instruction 1676628c6246SH. Peter Anvin (Intel Bull Mountain technology) to generate random numbers. 1677628c6246SH. Peter Anvin If supported, this is a high bandwidth, cryptographically 1678628c6246SH. Peter Anvin secure hardware random number generator. 1679628c6246SH. Peter Anvin 168051ae4a2dSH. Peter Anvinconfig X86_SMAP 168151ae4a2dSH. Peter Anvin def_bool y 168251ae4a2dSH. Peter Anvin prompt "Supervisor Mode Access Prevention" if EXPERT 168351ae4a2dSH. Peter Anvin ---help--- 168451ae4a2dSH. Peter Anvin Supervisor Mode Access Prevention (SMAP) is a security 168551ae4a2dSH. Peter Anvin feature in newer Intel processors. There is a small 168651ae4a2dSH. Peter Anvin performance cost if this enabled and turned on; there is 168751ae4a2dSH. Peter Anvin also a small increase in the kernel size if this is enabled. 168851ae4a2dSH. Peter Anvin 168951ae4a2dSH. Peter Anvin If unsure, say Y. 169051ae4a2dSH. Peter Anvin 169172e9b5feSDave Hansenconfig X86_INTEL_MPX 169272e9b5feSDave Hansen prompt "Intel MPX (Memory Protection Extensions)" 169372e9b5feSDave Hansen def_bool n 169472e9b5feSDave Hansen depends on CPU_SUP_INTEL 169572e9b5feSDave Hansen ---help--- 169672e9b5feSDave Hansen MPX provides hardware features that can be used in 169772e9b5feSDave Hansen conjunction with compiler-instrumented code to check 169872e9b5feSDave Hansen memory references. It is designed to detect buffer 169972e9b5feSDave Hansen overflow or underflow bugs. 170072e9b5feSDave Hansen 170172e9b5feSDave Hansen This option enables running applications which are 170272e9b5feSDave Hansen instrumented or otherwise use MPX. It does not use MPX 170372e9b5feSDave Hansen itself inside the kernel or to protect the kernel 170472e9b5feSDave Hansen against bad memory references. 170572e9b5feSDave Hansen 170672e9b5feSDave Hansen Enabling this option will make the kernel larger: 170772e9b5feSDave Hansen ~8k of kernel text and 36 bytes of data on a 64-bit 170872e9b5feSDave Hansen defconfig. It adds a long to the 'mm_struct' which 170972e9b5feSDave Hansen will increase the kernel memory overhead of each 171072e9b5feSDave Hansen process and adds some branches to paths used during 171172e9b5feSDave Hansen exec() and munmap(). 171272e9b5feSDave Hansen 171372e9b5feSDave Hansen For details, see Documentation/x86/intel_mpx.txt 171472e9b5feSDave Hansen 171572e9b5feSDave Hansen If unsure, say N. 171672e9b5feSDave Hansen 1717*35e97790SDave Hansenconfig X86_INTEL_MEMORY_PROTECTION_KEYS 1718*35e97790SDave Hansen def_bool y 1719*35e97790SDave Hansen depends on CPU_SUP_INTEL && X86_64 1720*35e97790SDave Hansen 1721506f1d07SSam Ravnborgconfig EFI 17229ba16087SJan Beulich bool "EFI runtime service support" 17235b83683fSHuang, Ying depends on ACPI 1724f6ce5002SSergey Vlasov select UCS2_STRING 1725022ee6c5SArd Biesheuvel select EFI_RUNTIME_WRAPPERS 1726506f1d07SSam Ravnborg ---help--- 17278b2cb7a8SHuang, Ying This enables the kernel to use EFI runtime services that are 1728506f1d07SSam Ravnborg available (such as the EFI variable services). 1729506f1d07SSam Ravnborg 17308b2cb7a8SHuang, Ying This option is only useful on systems that have EFI firmware. 17318b2cb7a8SHuang, Ying In addition, you should use the latest ELILO loader available 17328b2cb7a8SHuang, Ying at <http://elilo.sourceforge.net> in order to take advantage 17338b2cb7a8SHuang, Ying of EFI runtime services. However, even with this option, the 17348b2cb7a8SHuang, Ying resultant kernel should continue to boot on existing non-EFI 17358b2cb7a8SHuang, Ying platforms. 1736506f1d07SSam Ravnborg 1737291f3632SMatt Flemingconfig EFI_STUB 1738291f3632SMatt Fleming bool "EFI stub support" 1739b16d8c23SMatt Fleming depends on EFI && !X86_USE_3DNOW 17407b2a583aSMatt Fleming select RELOCATABLE 1741291f3632SMatt Fleming ---help--- 1742291f3632SMatt Fleming This kernel feature allows a bzImage to be loaded directly 1743291f3632SMatt Fleming by EFI firmware without the use of a bootloader. 1744291f3632SMatt Fleming 17454172fe2fSRoy Franz See Documentation/efi-stub.txt for more information. 17460c759662SMatt Fleming 17477d453eeeSMatt Flemingconfig EFI_MIXED 17487d453eeeSMatt Fleming bool "EFI mixed-mode support" 17497d453eeeSMatt Fleming depends on EFI_STUB && X86_64 17507d453eeeSMatt Fleming ---help--- 17517d453eeeSMatt Fleming Enabling this feature allows a 64-bit kernel to be booted 17527d453eeeSMatt Fleming on a 32-bit firmware, provided that your CPU supports 64-bit 17537d453eeeSMatt Fleming mode. 17547d453eeeSMatt Fleming 17557d453eeeSMatt Fleming Note that it is not possible to boot a mixed-mode enabled 17567d453eeeSMatt Fleming kernel via the EFI boot stub - a bootloader that supports 17577d453eeeSMatt Fleming the EFI handover protocol must be used. 17587d453eeeSMatt Fleming 17597d453eeeSMatt Fleming If unsure, say N. 17607d453eeeSMatt Fleming 1761506f1d07SSam Ravnborgconfig SECCOMP 17623c2362e6SHarvey Harrison def_bool y 17633c2362e6SHarvey Harrison prompt "Enable seccomp to safely compute untrusted bytecode" 17648f9ca475SIngo Molnar ---help--- 1765506f1d07SSam Ravnborg This kernel feature is useful for number crunching applications 1766506f1d07SSam Ravnborg that may need to compute untrusted bytecode during their 1767506f1d07SSam Ravnborg execution. By using pipes or other transports made available to 1768506f1d07SSam Ravnborg the process as file descriptors supporting the read/write 1769506f1d07SSam Ravnborg syscalls, it's possible to isolate those applications in 1770506f1d07SSam Ravnborg their own address space using seccomp. Once seccomp is 17719c0bbee8SAlexey Dobriyan enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 1772506f1d07SSam Ravnborg and the task is only allowed to execute a few safe syscalls 1773506f1d07SSam Ravnborg defined by each seccomp mode. 1774506f1d07SSam Ravnborg 1775506f1d07SSam Ravnborg If unsure, say Y. Only embedded should say N here. 1776506f1d07SSam Ravnborg 1777506f1d07SSam Ravnborgsource kernel/Kconfig.hz 1778506f1d07SSam Ravnborg 1779506f1d07SSam Ravnborgconfig KEXEC 1780506f1d07SSam Ravnborg bool "kexec system call" 17812965faa5SDave Young select KEXEC_CORE 17828f9ca475SIngo Molnar ---help--- 1783506f1d07SSam Ravnborg kexec is a system call that implements the ability to shutdown your 1784506f1d07SSam Ravnborg current kernel, and to start another kernel. It is like a reboot 1785506f1d07SSam Ravnborg but it is independent of the system firmware. And like a reboot 1786506f1d07SSam Ravnborg you can start any kernel with it, not just Linux. 1787506f1d07SSam Ravnborg 1788506f1d07SSam Ravnborg The name comes from the similarity to the exec system call. 1789506f1d07SSam Ravnborg 1790506f1d07SSam Ravnborg It is an ongoing process to be certain the hardware in a machine 1791506f1d07SSam Ravnborg is properly shutdown, so do not be surprised if this code does not 1792bf220695SGeert Uytterhoeven initially work for you. As of this writing the exact hardware 1793bf220695SGeert Uytterhoeven interface is strongly in flux, so no good recommendation can be 1794bf220695SGeert Uytterhoeven made. 1795506f1d07SSam Ravnborg 179674ca317cSVivek Goyalconfig KEXEC_FILE 179774ca317cSVivek Goyal bool "kexec file based system call" 17982965faa5SDave Young select KEXEC_CORE 179974ca317cSVivek Goyal select BUILD_BIN2C 180074ca317cSVivek Goyal depends on X86_64 180174ca317cSVivek Goyal depends on CRYPTO=y 180274ca317cSVivek Goyal depends on CRYPTO_SHA256=y 180374ca317cSVivek Goyal ---help--- 180474ca317cSVivek Goyal This is new version of kexec system call. This system call is 180574ca317cSVivek Goyal file based and takes file descriptors as system call argument 180674ca317cSVivek Goyal for kernel and initramfs as opposed to list of segments as 180774ca317cSVivek Goyal accepted by previous system call. 180874ca317cSVivek Goyal 18098e7d8381SVivek Goyalconfig KEXEC_VERIFY_SIG 18108e7d8381SVivek Goyal bool "Verify kernel signature during kexec_file_load() syscall" 181174ca317cSVivek Goyal depends on KEXEC_FILE 18128e7d8381SVivek Goyal ---help--- 18138e7d8381SVivek Goyal This option makes kernel signature verification mandatory for 1814d8eb8940SBorislav Petkov the kexec_file_load() syscall. 18158e7d8381SVivek Goyal 1816d8eb8940SBorislav Petkov In addition to that option, you need to enable signature 1817d8eb8940SBorislav Petkov verification for the corresponding kernel image type being 1818d8eb8940SBorislav Petkov loaded in order for this to work. 18198e7d8381SVivek Goyal 18208e7d8381SVivek Goyalconfig KEXEC_BZIMAGE_VERIFY_SIG 18218e7d8381SVivek Goyal bool "Enable bzImage signature verification support" 18228e7d8381SVivek Goyal depends on KEXEC_VERIFY_SIG 18238e7d8381SVivek Goyal depends on SIGNED_PE_FILE_VERIFICATION 18248e7d8381SVivek Goyal select SYSTEM_TRUSTED_KEYRING 18258e7d8381SVivek Goyal ---help--- 18268e7d8381SVivek Goyal Enable bzImage signature verification support. 18278e7d8381SVivek Goyal 1828506f1d07SSam Ravnborgconfig CRASH_DUMP 182904b69447SPavel Machek bool "kernel crash dumps" 1830506f1d07SSam Ravnborg depends on X86_64 || (X86_32 && HIGHMEM) 18318f9ca475SIngo Molnar ---help--- 1832506f1d07SSam Ravnborg Generate crash dump after being started by kexec. 1833506f1d07SSam Ravnborg This should be normally only set in special crash dump kernels 1834506f1d07SSam Ravnborg which are loaded in the main kernel with kexec-tools into 1835506f1d07SSam Ravnborg a specially reserved region and then later executed after 1836506f1d07SSam Ravnborg a crash by kdump/kexec. The crash dump kernel must be compiled 1837506f1d07SSam Ravnborg to a memory address not used by the main kernel or BIOS using 1838506f1d07SSam Ravnborg PHYSICAL_START, or it must be built as a relocatable image 1839506f1d07SSam Ravnborg (CONFIG_RELOCATABLE=y). 1840506f1d07SSam Ravnborg For more details see Documentation/kdump/kdump.txt 1841506f1d07SSam Ravnborg 18423ab83521SHuang Yingconfig KEXEC_JUMP 18436ea30386SKees Cook bool "kexec jump" 1844fee7b0d8SHuang Ying depends on KEXEC && HIBERNATION 18458f9ca475SIngo Molnar ---help--- 184689081d17SHuang Ying Jump between original kernel and kexeced kernel and invoke 184789081d17SHuang Ying code in physical address mode via KEXEC 18483ab83521SHuang Ying 1849506f1d07SSam Ravnborgconfig PHYSICAL_START 18506a108a14SDavid Rientjes hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP) 1851ceefccc9SH. Peter Anvin default "0x1000000" 18528f9ca475SIngo Molnar ---help--- 1853506f1d07SSam Ravnborg This gives the physical address where the kernel is loaded. 1854506f1d07SSam Ravnborg 1855506f1d07SSam Ravnborg If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then 1856506f1d07SSam Ravnborg bzImage will decompress itself to above physical address and 1857506f1d07SSam Ravnborg run from there. Otherwise, bzImage will run from the address where 1858506f1d07SSam Ravnborg it has been loaded by the boot loader and will ignore above physical 1859506f1d07SSam Ravnborg address. 1860506f1d07SSam Ravnborg 1861506f1d07SSam Ravnborg In normal kdump cases one does not have to set/change this option 1862506f1d07SSam Ravnborg as now bzImage can be compiled as a completely relocatable image 1863506f1d07SSam Ravnborg (CONFIG_RELOCATABLE=y) and be used to load and run from a different 1864506f1d07SSam Ravnborg address. This option is mainly useful for the folks who don't want 1865506f1d07SSam Ravnborg to use a bzImage for capturing the crash dump and want to use a 1866506f1d07SSam Ravnborg vmlinux instead. vmlinux is not relocatable hence a kernel needs 1867506f1d07SSam Ravnborg to be specifically compiled to run from a specific memory area 1868506f1d07SSam Ravnborg (normally a reserved region) and this option comes handy. 1869506f1d07SSam Ravnborg 1870ceefccc9SH. Peter Anvin So if you are using bzImage for capturing the crash dump, 1871ceefccc9SH. Peter Anvin leave the value here unchanged to 0x1000000 and set 1872ceefccc9SH. Peter Anvin CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux 1873ceefccc9SH. Peter Anvin for capturing the crash dump change this value to start of 1874ceefccc9SH. Peter Anvin the reserved region. In other words, it can be set based on 1875ceefccc9SH. Peter Anvin the "X" value as specified in the "crashkernel=YM@XM" 1876ceefccc9SH. Peter Anvin command line boot parameter passed to the panic-ed 1877ceefccc9SH. Peter Anvin kernel. Please take a look at Documentation/kdump/kdump.txt 1878ceefccc9SH. Peter Anvin for more details about crash dumps. 1879506f1d07SSam Ravnborg 1880506f1d07SSam Ravnborg Usage of bzImage for capturing the crash dump is recommended as 1881506f1d07SSam Ravnborg one does not have to build two kernels. Same kernel can be used 1882506f1d07SSam Ravnborg as production kernel and capture kernel. Above option should have 1883506f1d07SSam Ravnborg gone away after relocatable bzImage support is introduced. But it 1884506f1d07SSam Ravnborg is present because there are users out there who continue to use 1885506f1d07SSam Ravnborg vmlinux for dump capture. This option should go away down the 1886506f1d07SSam Ravnborg line. 1887506f1d07SSam Ravnborg 1888506f1d07SSam Ravnborg Don't change this unless you know what you are doing. 1889506f1d07SSam Ravnborg 1890506f1d07SSam Ravnborgconfig RELOCATABLE 189126717808SH. Peter Anvin bool "Build a relocatable kernel" 189226717808SH. Peter Anvin default y 18938f9ca475SIngo Molnar ---help--- 1894506f1d07SSam Ravnborg This builds a kernel image that retains relocation information 1895506f1d07SSam Ravnborg so it can be loaded someplace besides the default 1MB. 1896506f1d07SSam Ravnborg The relocations tend to make the kernel binary about 10% larger, 1897506f1d07SSam Ravnborg but are discarded at runtime. 1898506f1d07SSam Ravnborg 1899506f1d07SSam Ravnborg One use is for the kexec on panic case where the recovery kernel 1900506f1d07SSam Ravnborg must live at a different physical address than the primary 1901506f1d07SSam Ravnborg kernel. 1902506f1d07SSam Ravnborg 1903506f1d07SSam Ravnborg Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address 1904506f1d07SSam Ravnborg it has been loaded at and the compile time physical address 19058ab3820fSKees Cook (CONFIG_PHYSICAL_START) is used as the minimum location. 1906506f1d07SSam Ravnborg 19078ab3820fSKees Cookconfig RANDOMIZE_BASE 19088ab3820fSKees Cook bool "Randomize the address of the kernel image" 19098ab3820fSKees Cook depends on RELOCATABLE 19108ab3820fSKees Cook default n 19118ab3820fSKees Cook ---help--- 19128ab3820fSKees Cook Randomizes the physical and virtual address at which the 19138ab3820fSKees Cook kernel image is decompressed, as a security feature that 19148ab3820fSKees Cook deters exploit attempts relying on knowledge of the location 19158ab3820fSKees Cook of kernel internals. 19168ab3820fSKees Cook 1917a653f356SKees Cook Entropy is generated using the RDRAND instruction if it is 1918a653f356SKees Cook supported. If RDTSC is supported, it is used as well. If 1919a653f356SKees Cook neither RDRAND nor RDTSC are supported, then randomness is 1920a653f356SKees Cook read from the i8254 timer. 19218ab3820fSKees Cook 19228ab3820fSKees Cook The kernel will be offset by up to RANDOMIZE_BASE_MAX_OFFSET, 1923a653f356SKees Cook and aligned according to PHYSICAL_ALIGN. Since the kernel is 1924a653f356SKees Cook built using 2GiB addressing, and PHYSICAL_ALGIN must be at a 1925a653f356SKees Cook minimum of 2MiB, only 10 bits of entropy is theoretically 1926a653f356SKees Cook possible. At best, due to page table layouts, 64-bit can use 1927a653f356SKees Cook 9 bits of entropy and 32-bit uses 8 bits. 19288ab3820fSKees Cook 1929da2b6fb9SKees Cook If unsure, say N. 1930da2b6fb9SKees Cook 19318ab3820fSKees Cookconfig RANDOMIZE_BASE_MAX_OFFSET 1932da2b6fb9SKees Cook hex "Maximum kASLR offset allowed" if EXPERT 19338ab3820fSKees Cook depends on RANDOMIZE_BASE 19346145cfe3SKees Cook range 0x0 0x20000000 if X86_32 19356145cfe3SKees Cook default "0x20000000" if X86_32 19366145cfe3SKees Cook range 0x0 0x40000000 if X86_64 19376145cfe3SKees Cook default "0x40000000" if X86_64 19388ab3820fSKees Cook ---help--- 1939da2b6fb9SKees Cook The lesser of RANDOMIZE_BASE_MAX_OFFSET and available physical 1940da2b6fb9SKees Cook memory is used to determine the maximal offset in bytes that will 1941da2b6fb9SKees Cook be applied to the kernel when kernel Address Space Layout 1942da2b6fb9SKees Cook Randomization (kASLR) is active. This must be a multiple of 1943da2b6fb9SKees Cook PHYSICAL_ALIGN. 19446145cfe3SKees Cook 1945da2b6fb9SKees Cook On 32-bit this is limited to 512MiB by page table layouts. The 1946da2b6fb9SKees Cook default is 512MiB. 19476145cfe3SKees Cook 19486145cfe3SKees Cook On 64-bit this is limited by how the kernel fixmap page table is 1949da2b6fb9SKees Cook positioned, so this cannot be larger than 1GiB currently. Without 1950da2b6fb9SKees Cook RANDOMIZE_BASE, there is a 512MiB to 1.5GiB split between kernel 1951da2b6fb9SKees Cook and modules. When RANDOMIZE_BASE_MAX_OFFSET is above 512MiB, the 1952da2b6fb9SKees Cook modules area will shrink to compensate, up to the current maximum 1953da2b6fb9SKees Cook 1GiB to 1GiB split. The default is 1GiB. 1954da2b6fb9SKees Cook 1955da2b6fb9SKees Cook If unsure, leave at the default value. 19568ab3820fSKees Cook 19578ab3820fSKees Cook# Relocation on x86 needs some additional build support 1958845adf72SH. Peter Anvinconfig X86_NEED_RELOCS 1959845adf72SH. Peter Anvin def_bool y 19608ab3820fSKees Cook depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE) 1961845adf72SH. Peter Anvin 1962506f1d07SSam Ravnborgconfig PHYSICAL_ALIGN 1963a0215061SKees Cook hex "Alignment value to which kernel should be aligned" 19648ab3820fSKees Cook default "0x200000" 1965a0215061SKees Cook range 0x2000 0x1000000 if X86_32 1966a0215061SKees Cook range 0x200000 0x1000000 if X86_64 19678f9ca475SIngo Molnar ---help--- 1968506f1d07SSam Ravnborg This value puts the alignment restrictions on physical address 1969506f1d07SSam Ravnborg where kernel is loaded and run from. Kernel is compiled for an 1970506f1d07SSam Ravnborg address which meets above alignment restriction. 1971506f1d07SSam Ravnborg 1972506f1d07SSam Ravnborg If bootloader loads the kernel at a non-aligned address and 1973506f1d07SSam Ravnborg CONFIG_RELOCATABLE is set, kernel will move itself to nearest 1974506f1d07SSam Ravnborg address aligned to above value and run from there. 1975506f1d07SSam Ravnborg 1976506f1d07SSam Ravnborg If bootloader loads the kernel at a non-aligned address and 1977506f1d07SSam Ravnborg CONFIG_RELOCATABLE is not set, kernel will ignore the run time 1978506f1d07SSam Ravnborg load address and decompress itself to the address it has been 1979506f1d07SSam Ravnborg compiled for and run from there. The address for which kernel is 1980506f1d07SSam Ravnborg compiled already meets above alignment restrictions. Hence the 1981506f1d07SSam Ravnborg end result is that kernel runs from a physical address meeting 1982506f1d07SSam Ravnborg above alignment restrictions. 1983506f1d07SSam Ravnborg 1984a0215061SKees Cook On 32-bit this value must be a multiple of 0x2000. On 64-bit 1985a0215061SKees Cook this value must be a multiple of 0x200000. 1986a0215061SKees Cook 1987506f1d07SSam Ravnborg Don't change this unless you know what you are doing. 1988506f1d07SSam Ravnborg 1989506f1d07SSam Ravnborgconfig HOTPLUG_CPU 19907c13e6a3SDimitri Sivanich bool "Support for hot-pluggable CPUs" 199140b31360SStephen Rothwell depends on SMP 1992506f1d07SSam Ravnborg ---help--- 19937c13e6a3SDimitri Sivanich Say Y here to allow turning CPUs off and on. CPUs can be 19947c13e6a3SDimitri Sivanich controlled through /sys/devices/system/cpu. 19957c13e6a3SDimitri Sivanich ( Note: power management support will enable this option 19967c13e6a3SDimitri Sivanich automatically on SMP systems. ) 19977c13e6a3SDimitri Sivanich Say N if you want to disable CPU hotplug. 1998506f1d07SSam Ravnborg 199980aa1dffSFenghua Yuconfig BOOTPARAM_HOTPLUG_CPU0 200080aa1dffSFenghua Yu bool "Set default setting of cpu0_hotpluggable" 200180aa1dffSFenghua Yu default n 20022c922cd0SKees Cook depends on HOTPLUG_CPU 200380aa1dffSFenghua Yu ---help--- 200480aa1dffSFenghua Yu Set whether default state of cpu0_hotpluggable is on or off. 200580aa1dffSFenghua Yu 200680aa1dffSFenghua Yu Say Y here to enable CPU0 hotplug by default. If this switch 200780aa1dffSFenghua Yu is turned on, there is no need to give cpu0_hotplug kernel 200880aa1dffSFenghua Yu parameter and the CPU0 hotplug feature is enabled by default. 200980aa1dffSFenghua Yu 201080aa1dffSFenghua Yu Please note: there are two known CPU0 dependencies if you want 201180aa1dffSFenghua Yu to enable the CPU0 hotplug feature either by this switch or by 201280aa1dffSFenghua Yu cpu0_hotplug kernel parameter. 201380aa1dffSFenghua Yu 201480aa1dffSFenghua Yu First, resume from hibernate or suspend always starts from CPU0. 201580aa1dffSFenghua Yu So hibernate and suspend are prevented if CPU0 is offline. 201680aa1dffSFenghua Yu 201780aa1dffSFenghua Yu Second dependency is PIC interrupts always go to CPU0. CPU0 can not 201880aa1dffSFenghua Yu offline if any interrupt can not migrate out of CPU0. There may 201980aa1dffSFenghua Yu be other CPU0 dependencies. 202080aa1dffSFenghua Yu 202180aa1dffSFenghua Yu Please make sure the dependencies are under your control before 202280aa1dffSFenghua Yu you enable this feature. 202380aa1dffSFenghua Yu 202480aa1dffSFenghua Yu Say N if you don't want to enable CPU0 hotplug feature by default. 202580aa1dffSFenghua Yu You still can enable the CPU0 hotplug feature at boot by kernel 202680aa1dffSFenghua Yu parameter cpu0_hotplug. 202780aa1dffSFenghua Yu 2028a71c8bc5SFenghua Yuconfig DEBUG_HOTPLUG_CPU0 2029a71c8bc5SFenghua Yu def_bool n 2030a71c8bc5SFenghua Yu prompt "Debug CPU0 hotplug" 20312c922cd0SKees Cook depends on HOTPLUG_CPU 2032a71c8bc5SFenghua Yu ---help--- 2033a71c8bc5SFenghua Yu Enabling this option offlines CPU0 (if CPU0 can be offlined) as 2034a71c8bc5SFenghua Yu soon as possible and boots up userspace with CPU0 offlined. User 2035a71c8bc5SFenghua Yu can online CPU0 back after boot time. 2036a71c8bc5SFenghua Yu 2037a71c8bc5SFenghua Yu To debug CPU0 hotplug, you need to enable CPU0 offline/online 2038a71c8bc5SFenghua Yu feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during 2039a71c8bc5SFenghua Yu compilation or giving cpu0_hotplug kernel parameter at boot. 2040a71c8bc5SFenghua Yu 2041a71c8bc5SFenghua Yu If unsure, say N. 2042a71c8bc5SFenghua Yu 2043506f1d07SSam Ravnborgconfig COMPAT_VDSO 2044b0b49f26SAndy Lutomirski def_bool n 2045b0b49f26SAndy Lutomirski prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)" 2046af65d648SRoland McGrath depends on X86_32 || IA32_EMULATION 20478f9ca475SIngo Molnar ---help--- 2048b0b49f26SAndy Lutomirski Certain buggy versions of glibc will crash if they are 2049b0b49f26SAndy Lutomirski presented with a 32-bit vDSO that is not mapped at the address 2050b0b49f26SAndy Lutomirski indicated in its segment table. 2051e84446deSRandy Dunlap 2052b0b49f26SAndy Lutomirski The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a 2053b0b49f26SAndy Lutomirski and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and 2054b0b49f26SAndy Lutomirski 49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is 2055b0b49f26SAndy Lutomirski the only released version with the bug, but OpenSUSE 9 2056b0b49f26SAndy Lutomirski contains a buggy "glibc 2.3.2". 2057506f1d07SSam Ravnborg 2058b0b49f26SAndy Lutomirski The symptom of the bug is that everything crashes on startup, saying: 2059b0b49f26SAndy Lutomirski dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed! 2060b0b49f26SAndy Lutomirski 2061b0b49f26SAndy Lutomirski Saying Y here changes the default value of the vdso32 boot 2062b0b49f26SAndy Lutomirski option from 1 to 0, which turns off the 32-bit vDSO entirely. 2063b0b49f26SAndy Lutomirski This works around the glibc bug but hurts performance. 2064b0b49f26SAndy Lutomirski 2065b0b49f26SAndy Lutomirski If unsure, say N: if you are compiling your own kernel, you 2066b0b49f26SAndy Lutomirski are unlikely to be using a buggy version of glibc. 2067506f1d07SSam Ravnborg 20683dc33bd3SKees Cookchoice 20693dc33bd3SKees Cook prompt "vsyscall table for legacy applications" 20703dc33bd3SKees Cook depends on X86_64 20713dc33bd3SKees Cook default LEGACY_VSYSCALL_EMULATE 20723dc33bd3SKees Cook help 20733dc33bd3SKees Cook Legacy user code that does not know how to find the vDSO expects 20743dc33bd3SKees Cook to be able to issue three syscalls by calling fixed addresses in 20753dc33bd3SKees Cook kernel space. Since this location is not randomized with ASLR, 20763dc33bd3SKees Cook it can be used to assist security vulnerability exploitation. 20773dc33bd3SKees Cook 20783dc33bd3SKees Cook This setting can be changed at boot time via the kernel command 20793dc33bd3SKees Cook line parameter vsyscall=[native|emulate|none]. 20803dc33bd3SKees Cook 20813dc33bd3SKees Cook On a system with recent enough glibc (2.14 or newer) and no 20823dc33bd3SKees Cook static binaries, you can say None without a performance penalty 20833dc33bd3SKees Cook to improve security. 20843dc33bd3SKees Cook 20853dc33bd3SKees Cook If unsure, select "Emulate". 20863dc33bd3SKees Cook 20873dc33bd3SKees Cook config LEGACY_VSYSCALL_NATIVE 20883dc33bd3SKees Cook bool "Native" 20893dc33bd3SKees Cook help 20903dc33bd3SKees Cook Actual executable code is located in the fixed vsyscall 20913dc33bd3SKees Cook address mapping, implementing time() efficiently. Since 20923dc33bd3SKees Cook this makes the mapping executable, it can be used during 20933dc33bd3SKees Cook security vulnerability exploitation (traditionally as 20943dc33bd3SKees Cook ROP gadgets). This configuration is not recommended. 20953dc33bd3SKees Cook 20963dc33bd3SKees Cook config LEGACY_VSYSCALL_EMULATE 20973dc33bd3SKees Cook bool "Emulate" 20983dc33bd3SKees Cook help 20993dc33bd3SKees Cook The kernel traps and emulates calls into the fixed 21003dc33bd3SKees Cook vsyscall address mapping. This makes the mapping 21013dc33bd3SKees Cook non-executable, but it still contains known contents, 21023dc33bd3SKees Cook which could be used in certain rare security vulnerability 21033dc33bd3SKees Cook exploits. This configuration is recommended when userspace 21043dc33bd3SKees Cook still uses the vsyscall area. 21053dc33bd3SKees Cook 21063dc33bd3SKees Cook config LEGACY_VSYSCALL_NONE 21073dc33bd3SKees Cook bool "None" 21083dc33bd3SKees Cook help 21093dc33bd3SKees Cook There will be no vsyscall mapping at all. This will 21103dc33bd3SKees Cook eliminate any risk of ASLR bypass due to the vsyscall 21113dc33bd3SKees Cook fixed address mapping. Attempts to use the vsyscalls 21123dc33bd3SKees Cook will be reported to dmesg, so that either old or 21133dc33bd3SKees Cook malicious userspace programs can be identified. 21143dc33bd3SKees Cook 21153dc33bd3SKees Cookendchoice 21163dc33bd3SKees Cook 2117516cbf37STim Birdconfig CMDLINE_BOOL 2118516cbf37STim Bird bool "Built-in kernel command line" 21198f9ca475SIngo Molnar ---help--- 2120516cbf37STim Bird Allow for specifying boot arguments to the kernel at 2121516cbf37STim Bird build time. On some systems (e.g. embedded ones), it is 2122516cbf37STim Bird necessary or convenient to provide some or all of the 2123516cbf37STim Bird kernel boot arguments with the kernel itself (that is, 2124516cbf37STim Bird to not rely on the boot loader to provide them.) 2125516cbf37STim Bird 2126516cbf37STim Bird To compile command line arguments into the kernel, 2127516cbf37STim Bird set this option to 'Y', then fill in the 212869711ca1SSébastien Hinderer boot arguments in CONFIG_CMDLINE. 2129516cbf37STim Bird 2130516cbf37STim Bird Systems with fully functional boot loaders (i.e. non-embedded) 2131516cbf37STim Bird should leave this option set to 'N'. 2132516cbf37STim Bird 2133516cbf37STim Birdconfig CMDLINE 2134516cbf37STim Bird string "Built-in kernel command string" 2135516cbf37STim Bird depends on CMDLINE_BOOL 2136516cbf37STim Bird default "" 21378f9ca475SIngo Molnar ---help--- 2138516cbf37STim Bird Enter arguments here that should be compiled into the kernel 2139516cbf37STim Bird image and used at boot time. If the boot loader provides a 2140516cbf37STim Bird command line at boot time, it is appended to this string to 2141516cbf37STim Bird form the full kernel command line, when the system boots. 2142516cbf37STim Bird 2143516cbf37STim Bird However, you can use the CONFIG_CMDLINE_OVERRIDE option to 2144516cbf37STim Bird change this behavior. 2145516cbf37STim Bird 2146516cbf37STim Bird In most cases, the command line (whether built-in or provided 2147516cbf37STim Bird by the boot loader) should specify the device for the root 2148516cbf37STim Bird file system. 2149516cbf37STim Bird 2150516cbf37STim Birdconfig CMDLINE_OVERRIDE 2151516cbf37STim Bird bool "Built-in command line overrides boot loader arguments" 2152516cbf37STim Bird depends on CMDLINE_BOOL 21538f9ca475SIngo Molnar ---help--- 2154516cbf37STim Bird Set this option to 'Y' to have the kernel ignore the boot loader 2155516cbf37STim Bird command line, and use ONLY the built-in command line. 2156516cbf37STim Bird 2157516cbf37STim Bird This is used to work around broken boot loaders. This should 2158516cbf37STim Bird be set to 'N' under normal conditions. 2159516cbf37STim Bird 2160a5b9e5a2SAndy Lutomirskiconfig MODIFY_LDT_SYSCALL 2161a5b9e5a2SAndy Lutomirski bool "Enable the LDT (local descriptor table)" if EXPERT 2162a5b9e5a2SAndy Lutomirski default y 2163a5b9e5a2SAndy Lutomirski ---help--- 2164a5b9e5a2SAndy Lutomirski Linux can allow user programs to install a per-process x86 2165a5b9e5a2SAndy Lutomirski Local Descriptor Table (LDT) using the modify_ldt(2) system 2166a5b9e5a2SAndy Lutomirski call. This is required to run 16-bit or segmented code such as 2167a5b9e5a2SAndy Lutomirski DOSEMU or some Wine programs. It is also used by some very old 2168a5b9e5a2SAndy Lutomirski threading libraries. 2169a5b9e5a2SAndy Lutomirski 2170a5b9e5a2SAndy Lutomirski Enabling this feature adds a small amount of overhead to 2171a5b9e5a2SAndy Lutomirski context switches and increases the low-level kernel attack 2172a5b9e5a2SAndy Lutomirski surface. Disabling it removes the modify_ldt(2) system call. 2173a5b9e5a2SAndy Lutomirski 2174a5b9e5a2SAndy Lutomirski Saying 'N' here may make sense for embedded or server kernels. 2175a5b9e5a2SAndy Lutomirski 2176b700e7f0SSeth Jenningssource "kernel/livepatch/Kconfig" 2177b700e7f0SSeth Jennings 2178506f1d07SSam Ravnborgendmenu 2179506f1d07SSam Ravnborg 2180506f1d07SSam Ravnborgconfig ARCH_ENABLE_MEMORY_HOTPLUG 2181506f1d07SSam Ravnborg def_bool y 2182506f1d07SSam Ravnborg depends on X86_64 || (X86_32 && HIGHMEM) 2183506f1d07SSam Ravnborg 218435551053SGary Hadeconfig ARCH_ENABLE_MEMORY_HOTREMOVE 218535551053SGary Hade def_bool y 218635551053SGary Hade depends on MEMORY_HOTPLUG 218735551053SGary Hade 2188e534c7c5SLee Schermerhornconfig USE_PERCPU_NUMA_NODE_ID 2189645a7919STejun Heo def_bool y 2190e534c7c5SLee Schermerhorn depends on NUMA 2191e534c7c5SLee Schermerhorn 21929491846fSKirill A. Shutemovconfig ARCH_ENABLE_SPLIT_PMD_PTLOCK 21939491846fSKirill A. Shutemov def_bool y 21949491846fSKirill A. Shutemov depends on X86_64 || X86_PAE 21959491846fSKirill A. Shutemov 2196c177c81eSNaoya Horiguchiconfig ARCH_ENABLE_HUGEPAGE_MIGRATION 2197c177c81eSNaoya Horiguchi def_bool y 2198c177c81eSNaoya Horiguchi depends on X86_64 && HUGETLB_PAGE && MIGRATION 2199c177c81eSNaoya Horiguchi 2200da85f865SBjorn Helgaasmenu "Power management and ACPI options" 2201e279b6c1SSam Ravnborg 2202e279b6c1SSam Ravnborgconfig ARCH_HIBERNATION_HEADER 22033c2362e6SHarvey Harrison def_bool y 2204e279b6c1SSam Ravnborg depends on X86_64 && HIBERNATION 2205e279b6c1SSam Ravnborg 2206e279b6c1SSam Ravnborgsource "kernel/power/Kconfig" 2207e279b6c1SSam Ravnborg 2208e279b6c1SSam Ravnborgsource "drivers/acpi/Kconfig" 2209e279b6c1SSam Ravnborg 2210efafc8b2SFeng Tangsource "drivers/sfi/Kconfig" 2211efafc8b2SFeng Tang 2212a6b68076SAndi Kleenconfig X86_APM_BOOT 22136fc108a0SJan Beulich def_bool y 2214282e5aabSPaul Bolle depends on APM 2215a6b68076SAndi Kleen 2216e279b6c1SSam Ravnborgmenuconfig APM 2217e279b6c1SSam Ravnborg tristate "APM (Advanced Power Management) BIOS support" 2218efefa6f6SIngo Molnar depends on X86_32 && PM_SLEEP 2219e279b6c1SSam Ravnborg ---help--- 2220e279b6c1SSam Ravnborg APM is a BIOS specification for saving power using several different 2221e279b6c1SSam Ravnborg techniques. This is mostly useful for battery powered laptops with 2222e279b6c1SSam Ravnborg APM compliant BIOSes. If you say Y here, the system time will be 2223e279b6c1SSam Ravnborg reset after a RESUME operation, the /proc/apm device will provide 2224e279b6c1SSam Ravnborg battery status information, and user-space programs will receive 2225e279b6c1SSam Ravnborg notification of APM "events" (e.g. battery status change). 2226e279b6c1SSam Ravnborg 2227e279b6c1SSam Ravnborg If you select "Y" here, you can disable actual use of the APM 2228e279b6c1SSam Ravnborg BIOS by passing the "apm=off" option to the kernel at boot time. 2229e279b6c1SSam Ravnborg 2230e279b6c1SSam Ravnborg Note that the APM support is almost completely disabled for 2231e279b6c1SSam Ravnborg machines with more than one CPU. 2232e279b6c1SSam Ravnborg 2233e279b6c1SSam Ravnborg In order to use APM, you will need supporting software. For location 22342dc98fd3SMichael Witten and more information, read <file:Documentation/power/apm-acpi.txt> 22352dc98fd3SMichael Witten and the Battery Powered Linux mini-HOWTO, available from 2236e279b6c1SSam Ravnborg <http://www.tldp.org/docs.html#howto>. 2237e279b6c1SSam Ravnborg 2238e279b6c1SSam Ravnborg This driver does not spin down disk drives (see the hdparm(8) 2239e279b6c1SSam Ravnborg manpage ("man 8 hdparm") for that), and it doesn't turn off 2240e279b6c1SSam Ravnborg VESA-compliant "green" monitors. 2241e279b6c1SSam Ravnborg 2242e279b6c1SSam Ravnborg This driver does not support the TI 4000M TravelMate and the ACER 2243e279b6c1SSam Ravnborg 486/DX4/75 because they don't have compliant BIOSes. Many "green" 2244e279b6c1SSam Ravnborg desktop machines also don't have compliant BIOSes, and this driver 2245e279b6c1SSam Ravnborg may cause those machines to panic during the boot phase. 2246e279b6c1SSam Ravnborg 2247e279b6c1SSam Ravnborg Generally, if you don't have a battery in your machine, there isn't 2248e279b6c1SSam Ravnborg much point in using this driver and you should say N. If you get 2249e279b6c1SSam Ravnborg random kernel OOPSes or reboots that don't seem to be related to 2250e279b6c1SSam Ravnborg anything, try disabling/enabling this option (or disabling/enabling 2251e279b6c1SSam Ravnborg APM in your BIOS). 2252e279b6c1SSam Ravnborg 2253e279b6c1SSam Ravnborg Some other things you should try when experiencing seemingly random, 2254e279b6c1SSam Ravnborg "weird" problems: 2255e279b6c1SSam Ravnborg 2256e279b6c1SSam Ravnborg 1) make sure that you have enough swap space and that it is 2257e279b6c1SSam Ravnborg enabled. 2258e279b6c1SSam Ravnborg 2) pass the "no-hlt" option to the kernel 2259e279b6c1SSam Ravnborg 3) switch on floating point emulation in the kernel and pass 2260e279b6c1SSam Ravnborg the "no387" option to the kernel 2261e279b6c1SSam Ravnborg 4) pass the "floppy=nodma" option to the kernel 2262e279b6c1SSam Ravnborg 5) pass the "mem=4M" option to the kernel (thereby disabling 2263e279b6c1SSam Ravnborg all but the first 4 MB of RAM) 2264e279b6c1SSam Ravnborg 6) make sure that the CPU is not over clocked. 2265e279b6c1SSam Ravnborg 7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> 2266e279b6c1SSam Ravnborg 8) disable the cache from your BIOS settings 2267e279b6c1SSam Ravnborg 9) install a fan for the video card or exchange video RAM 2268e279b6c1SSam Ravnborg 10) install a better fan for the CPU 2269e279b6c1SSam Ravnborg 11) exchange RAM chips 2270e279b6c1SSam Ravnborg 12) exchange the motherboard. 2271e279b6c1SSam Ravnborg 2272e279b6c1SSam Ravnborg To compile this driver as a module, choose M here: the 2273e279b6c1SSam Ravnborg module will be called apm. 2274e279b6c1SSam Ravnborg 2275e279b6c1SSam Ravnborgif APM 2276e279b6c1SSam Ravnborg 2277e279b6c1SSam Ravnborgconfig APM_IGNORE_USER_SUSPEND 2278e279b6c1SSam Ravnborg bool "Ignore USER SUSPEND" 22798f9ca475SIngo Molnar ---help--- 2280e279b6c1SSam Ravnborg This option will ignore USER SUSPEND requests. On machines with a 2281e279b6c1SSam Ravnborg compliant APM BIOS, you want to say N. However, on the NEC Versa M 2282e279b6c1SSam Ravnborg series notebooks, it is necessary to say Y because of a BIOS bug. 2283e279b6c1SSam Ravnborg 2284e279b6c1SSam Ravnborgconfig APM_DO_ENABLE 2285e279b6c1SSam Ravnborg bool "Enable PM at boot time" 2286e279b6c1SSam Ravnborg ---help--- 2287e279b6c1SSam Ravnborg Enable APM features at boot time. From page 36 of the APM BIOS 2288e279b6c1SSam Ravnborg specification: "When disabled, the APM BIOS does not automatically 2289e279b6c1SSam Ravnborg power manage devices, enter the Standby State, enter the Suspend 2290e279b6c1SSam Ravnborg State, or take power saving steps in response to CPU Idle calls." 2291e279b6c1SSam Ravnborg This driver will make CPU Idle calls when Linux is idle (unless this 2292e279b6c1SSam Ravnborg feature is turned off -- see "Do CPU IDLE calls", below). This 2293e279b6c1SSam Ravnborg should always save battery power, but more complicated APM features 2294e279b6c1SSam Ravnborg will be dependent on your BIOS implementation. You may need to turn 2295e279b6c1SSam Ravnborg this option off if your computer hangs at boot time when using APM 2296e279b6c1SSam Ravnborg support, or if it beeps continuously instead of suspending. Turn 2297e279b6c1SSam Ravnborg this off if you have a NEC UltraLite Versa 33/C or a Toshiba 2298e279b6c1SSam Ravnborg T400CDT. This is off by default since most machines do fine without 2299e279b6c1SSam Ravnborg this feature. 2300e279b6c1SSam Ravnborg 2301e279b6c1SSam Ravnborgconfig APM_CPU_IDLE 2302dd8af076SLen Brown depends on CPU_IDLE 2303e279b6c1SSam Ravnborg bool "Make CPU Idle calls when idle" 23048f9ca475SIngo Molnar ---help--- 2305e279b6c1SSam Ravnborg Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. 2306e279b6c1SSam Ravnborg On some machines, this can activate improved power savings, such as 2307e279b6c1SSam Ravnborg a slowed CPU clock rate, when the machine is idle. These idle calls 2308e279b6c1SSam Ravnborg are made after the idle loop has run for some length of time (e.g., 2309e279b6c1SSam Ravnborg 333 mS). On some machines, this will cause a hang at boot time or 2310e279b6c1SSam Ravnborg whenever the CPU becomes idle. (On machines with more than one CPU, 2311e279b6c1SSam Ravnborg this option does nothing.) 2312e279b6c1SSam Ravnborg 2313e279b6c1SSam Ravnborgconfig APM_DISPLAY_BLANK 2314e279b6c1SSam Ravnborg bool "Enable console blanking using APM" 23158f9ca475SIngo Molnar ---help--- 2316e279b6c1SSam Ravnborg Enable console blanking using the APM. Some laptops can use this to 2317e279b6c1SSam Ravnborg turn off the LCD backlight when the screen blanker of the Linux 2318e279b6c1SSam Ravnborg virtual console blanks the screen. Note that this is only used by 2319e279b6c1SSam Ravnborg the virtual console screen blanker, and won't turn off the backlight 2320e279b6c1SSam Ravnborg when using the X Window system. This also doesn't have anything to 2321e279b6c1SSam Ravnborg do with your VESA-compliant power-saving monitor. Further, this 2322e279b6c1SSam Ravnborg option doesn't work for all laptops -- it might not turn off your 2323e279b6c1SSam Ravnborg backlight at all, or it might print a lot of errors to the console, 2324e279b6c1SSam Ravnborg especially if you are using gpm. 2325e279b6c1SSam Ravnborg 2326e279b6c1SSam Ravnborgconfig APM_ALLOW_INTS 2327e279b6c1SSam Ravnborg bool "Allow interrupts during APM BIOS calls" 23288f9ca475SIngo Molnar ---help--- 2329e279b6c1SSam Ravnborg Normally we disable external interrupts while we are making calls to 2330e279b6c1SSam Ravnborg the APM BIOS as a measure to lessen the effects of a badly behaving 2331e279b6c1SSam Ravnborg BIOS implementation. The BIOS should reenable interrupts if it 2332e279b6c1SSam Ravnborg needs to. Unfortunately, some BIOSes do not -- especially those in 2333e279b6c1SSam Ravnborg many of the newer IBM Thinkpads. If you experience hangs when you 2334e279b6c1SSam Ravnborg suspend, try setting this to Y. Otherwise, say N. 2335e279b6c1SSam Ravnborg 2336e279b6c1SSam Ravnborgendif # APM 2337e279b6c1SSam Ravnborg 2338bb0a56ecSDave Jonessource "drivers/cpufreq/Kconfig" 2339e279b6c1SSam Ravnborg 2340e279b6c1SSam Ravnborgsource "drivers/cpuidle/Kconfig" 2341e279b6c1SSam Ravnborg 234227471fdbSAndy Henroidsource "drivers/idle/Kconfig" 234327471fdbSAndy Henroid 2344e279b6c1SSam Ravnborgendmenu 2345e279b6c1SSam Ravnborg 2346e279b6c1SSam Ravnborg 2347e279b6c1SSam Ravnborgmenu "Bus options (PCI etc.)" 2348e279b6c1SSam Ravnborg 2349e279b6c1SSam Ravnborgconfig PCI 23501ac97018SIngo Molnar bool "PCI support" 23511c858087SAdrian Bunk default y 23528f9ca475SIngo Molnar ---help--- 2353e279b6c1SSam Ravnborg Find out whether you have a PCI motherboard. PCI is the name of a 2354e279b6c1SSam Ravnborg bus system, i.e. the way the CPU talks to the other stuff inside 2355e279b6c1SSam Ravnborg your box. Other bus systems are ISA, EISA, MicroChannel (MCA) or 2356e279b6c1SSam Ravnborg VESA. If you have PCI, say Y, otherwise N. 2357e279b6c1SSam Ravnborg 2358e279b6c1SSam Ravnborgchoice 2359e279b6c1SSam Ravnborg prompt "PCI access mode" 2360efefa6f6SIngo Molnar depends on X86_32 && PCI 2361e279b6c1SSam Ravnborg default PCI_GOANY 2362e279b6c1SSam Ravnborg ---help--- 2363e279b6c1SSam Ravnborg On PCI systems, the BIOS can be used to detect the PCI devices and 2364e279b6c1SSam Ravnborg determine their configuration. However, some old PCI motherboards 2365e279b6c1SSam Ravnborg have BIOS bugs and may crash if this is done. Also, some embedded 2366e279b6c1SSam Ravnborg PCI-based systems don't have any BIOS at all. Linux can also try to 2367e279b6c1SSam Ravnborg detect the PCI hardware directly without using the BIOS. 2368e279b6c1SSam Ravnborg 2369e279b6c1SSam Ravnborg With this option, you can specify how Linux should detect the 2370e279b6c1SSam Ravnborg PCI devices. If you choose "BIOS", the BIOS will be used, 2371e279b6c1SSam Ravnborg if you choose "Direct", the BIOS won't be used, and if you 2372e279b6c1SSam Ravnborg choose "MMConfig", then PCI Express MMCONFIG will be used. 2373e279b6c1SSam Ravnborg If you choose "Any", the kernel will try MMCONFIG, then the 2374e279b6c1SSam Ravnborg direct access method and falls back to the BIOS if that doesn't 2375e279b6c1SSam Ravnborg work. If unsure, go with the default, which is "Any". 2376e279b6c1SSam Ravnborg 2377e279b6c1SSam Ravnborgconfig PCI_GOBIOS 2378e279b6c1SSam Ravnborg bool "BIOS" 2379e279b6c1SSam Ravnborg 2380e279b6c1SSam Ravnborgconfig PCI_GOMMCONFIG 2381e279b6c1SSam Ravnborg bool "MMConfig" 2382e279b6c1SSam Ravnborg 2383e279b6c1SSam Ravnborgconfig PCI_GODIRECT 2384e279b6c1SSam Ravnborg bool "Direct" 2385e279b6c1SSam Ravnborg 23863ef0e1f8SAndres Salomonconfig PCI_GOOLPC 238776fb6570SDaniel Drake bool "OLPC XO-1" 23883ef0e1f8SAndres Salomon depends on OLPC 23893ef0e1f8SAndres Salomon 23902bdd1b03SAndres Salomonconfig PCI_GOANY 23912bdd1b03SAndres Salomon bool "Any" 23922bdd1b03SAndres Salomon 2393e279b6c1SSam Ravnborgendchoice 2394e279b6c1SSam Ravnborg 2395e279b6c1SSam Ravnborgconfig PCI_BIOS 23963c2362e6SHarvey Harrison def_bool y 2397efefa6f6SIngo Molnar depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY) 2398e279b6c1SSam Ravnborg 2399e279b6c1SSam Ravnborg# x86-64 doesn't support PCI BIOS access from long mode so always go direct. 2400e279b6c1SSam Ravnborgconfig PCI_DIRECT 24013c2362e6SHarvey Harrison def_bool y 24020aba496fSShaohua Li depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG)) 2403e279b6c1SSam Ravnborg 2404e279b6c1SSam Ravnborgconfig PCI_MMCONFIG 24053c2362e6SHarvey Harrison def_bool y 24065f0db7a2SFeng Tang depends on X86_32 && PCI && (ACPI || SFI) && (PCI_GOMMCONFIG || PCI_GOANY) 2407e279b6c1SSam Ravnborg 24083ef0e1f8SAndres Salomonconfig PCI_OLPC 24092bdd1b03SAndres Salomon def_bool y 24102bdd1b03SAndres Salomon depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY) 24113ef0e1f8SAndres Salomon 2412b5401a96SAlex Nixonconfig PCI_XEN 2413b5401a96SAlex Nixon def_bool y 2414b5401a96SAlex Nixon depends on PCI && XEN 2415b5401a96SAlex Nixon select SWIOTLB_XEN 2416b5401a96SAlex Nixon 2417e279b6c1SSam Ravnborgconfig PCI_DOMAINS 24183c2362e6SHarvey Harrison def_bool y 2419e279b6c1SSam Ravnborg depends on PCI 2420e279b6c1SSam Ravnborg 2421e279b6c1SSam Ravnborgconfig PCI_MMCONFIG 2422e279b6c1SSam Ravnborg bool "Support mmconfig PCI config space access" 2423e279b6c1SSam Ravnborg depends on X86_64 && PCI && ACPI 2424e279b6c1SSam Ravnborg 24253f6ea84aSIra W. Snyderconfig PCI_CNB20LE_QUIRK 24266a108a14SDavid Rientjes bool "Read CNB20LE Host Bridge Windows" if EXPERT 24276ea30386SKees Cook depends on PCI 24283f6ea84aSIra W. Snyder help 24293f6ea84aSIra W. Snyder Read the PCI windows out of the CNB20LE host bridge. This allows 24303f6ea84aSIra W. Snyder PCI hotplug to work on systems with the CNB20LE chipset which do 24313f6ea84aSIra W. Snyder not have ACPI. 24323f6ea84aSIra W. Snyder 243364a5fed6SBjorn Helgaas There's no public spec for this chipset, and this functionality 243464a5fed6SBjorn Helgaas is known to be incomplete. 243564a5fed6SBjorn Helgaas 243664a5fed6SBjorn Helgaas You should say N unless you know you need this. 243764a5fed6SBjorn Helgaas 2438e279b6c1SSam Ravnborgsource "drivers/pci/pcie/Kconfig" 2439e279b6c1SSam Ravnborg 2440e279b6c1SSam Ravnborgsource "drivers/pci/Kconfig" 2441e279b6c1SSam Ravnborg 24421c00f016SDavid Rientjes# x86_64 have no ISA slots, but can have ISA-style DMA. 2443e279b6c1SSam Ravnborgconfig ISA_DMA_API 24441c00f016SDavid Rientjes bool "ISA-style DMA support" if (X86_64 && EXPERT) 24451c00f016SDavid Rientjes default y 24461c00f016SDavid Rientjes help 24471c00f016SDavid Rientjes Enables ISA-style DMA support for devices requiring such controllers. 24481c00f016SDavid Rientjes If unsure, say Y. 2449e279b6c1SSam Ravnborg 2450e279b6c1SSam Ravnborgif X86_32 2451e279b6c1SSam Ravnborg 2452e279b6c1SSam Ravnborgconfig ISA 2453e279b6c1SSam Ravnborg bool "ISA support" 24548f9ca475SIngo Molnar ---help--- 2455e279b6c1SSam Ravnborg Find out whether you have ISA slots on your motherboard. ISA is the 2456e279b6c1SSam Ravnborg name of a bus system, i.e. the way the CPU talks to the other stuff 2457e279b6c1SSam Ravnborg inside your box. Other bus systems are PCI, EISA, MicroChannel 2458e279b6c1SSam Ravnborg (MCA) or VESA. ISA is an older system, now being displaced by PCI; 2459e279b6c1SSam Ravnborg newer boards don't support it. If you have ISA, say Y, otherwise N. 2460e279b6c1SSam Ravnborg 2461e279b6c1SSam Ravnborgconfig EISA 2462e279b6c1SSam Ravnborg bool "EISA support" 2463e279b6c1SSam Ravnborg depends on ISA 2464e279b6c1SSam Ravnborg ---help--- 2465e279b6c1SSam Ravnborg The Extended Industry Standard Architecture (EISA) bus was 2466e279b6c1SSam Ravnborg developed as an open alternative to the IBM MicroChannel bus. 2467e279b6c1SSam Ravnborg 2468e279b6c1SSam Ravnborg The EISA bus provided some of the features of the IBM MicroChannel 2469e279b6c1SSam Ravnborg bus while maintaining backward compatibility with cards made for 2470e279b6c1SSam Ravnborg the older ISA bus. The EISA bus saw limited use between 1988 and 2471e279b6c1SSam Ravnborg 1995 when it was made obsolete by the PCI bus. 2472e279b6c1SSam Ravnborg 2473e279b6c1SSam Ravnborg Say Y here if you are building a kernel for an EISA-based machine. 2474e279b6c1SSam Ravnborg 2475e279b6c1SSam Ravnborg Otherwise, say N. 2476e279b6c1SSam Ravnborg 2477e279b6c1SSam Ravnborgsource "drivers/eisa/Kconfig" 2478e279b6c1SSam Ravnborg 2479e279b6c1SSam Ravnborgconfig SCx200 2480e279b6c1SSam Ravnborg tristate "NatSemi SCx200 support" 24818f9ca475SIngo Molnar ---help--- 2482e279b6c1SSam Ravnborg This provides basic support for National Semiconductor's 2483e279b6c1SSam Ravnborg (now AMD's) Geode processors. The driver probes for the 2484e279b6c1SSam Ravnborg PCI-IDs of several on-chip devices, so its a good dependency 2485e279b6c1SSam Ravnborg for other scx200_* drivers. 2486e279b6c1SSam Ravnborg 2487e279b6c1SSam Ravnborg If compiled as a module, the driver is named scx200. 2488e279b6c1SSam Ravnborg 2489e279b6c1SSam Ravnborgconfig SCx200HR_TIMER 2490e279b6c1SSam Ravnborg tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" 2491592913ecSJohn Stultz depends on SCx200 2492e279b6c1SSam Ravnborg default y 24938f9ca475SIngo Molnar ---help--- 2494e279b6c1SSam Ravnborg This driver provides a clocksource built upon the on-chip 2495e279b6c1SSam Ravnborg 27MHz high-resolution timer. Its also a workaround for 2496e279b6c1SSam Ravnborg NSC Geode SC-1100's buggy TSC, which loses time when the 2497e279b6c1SSam Ravnborg processor goes idle (as is done by the scheduler). The 2498e279b6c1SSam Ravnborg other workaround is idle=poll boot option. 2499e279b6c1SSam Ravnborg 25003ef0e1f8SAndres Salomonconfig OLPC 25013ef0e1f8SAndres Salomon bool "One Laptop Per Child support" 250254008979SThomas Gleixner depends on !X86_PAE 25033c554946SAndres Salomon select GPIOLIB 2504dc3119e7SThomas Gleixner select OF 250545bb1674SDaniel Drake select OF_PROMTREE 2506b4e51854SGrant Likely select IRQ_DOMAIN 25078f9ca475SIngo Molnar ---help--- 25083ef0e1f8SAndres Salomon Add support for detecting the unique features of the OLPC 25093ef0e1f8SAndres Salomon XO hardware. 25103ef0e1f8SAndres Salomon 2511a3128588SDaniel Drakeconfig OLPC_XO1_PM 2512a3128588SDaniel Drake bool "OLPC XO-1 Power Management" 251397c4cb71SDaniel Drake depends on OLPC && MFD_CS5535 && PM_SLEEP 2514a3128588SDaniel Drake select MFD_CORE 2515bf1ebf00SDaniel Drake ---help--- 251697c4cb71SDaniel Drake Add support for poweroff and suspend of the OLPC XO-1 laptop. 2517bf1ebf00SDaniel Drake 2518cfee9597SDaniel Drakeconfig OLPC_XO1_RTC 2519cfee9597SDaniel Drake bool "OLPC XO-1 Real Time Clock" 2520cfee9597SDaniel Drake depends on OLPC_XO1_PM && RTC_DRV_CMOS 2521cfee9597SDaniel Drake ---help--- 2522cfee9597SDaniel Drake Add support for the XO-1 real time clock, which can be used as a 2523cfee9597SDaniel Drake programmable wakeup source. 2524cfee9597SDaniel Drake 25257feda8e9SDaniel Drakeconfig OLPC_XO1_SCI 25267feda8e9SDaniel Drake bool "OLPC XO-1 SCI extras" 2527d8d01a63SDaniel Drake depends on OLPC && OLPC_XO1_PM 2528ed8e47feSRandy Dunlap depends on INPUT=y 2529d8d01a63SDaniel Drake select POWER_SUPPLY 25307feda8e9SDaniel Drake select GPIO_CS5535 25317feda8e9SDaniel Drake select MFD_CORE 25327feda8e9SDaniel Drake ---help--- 25337feda8e9SDaniel Drake Add support for SCI-based features of the OLPC XO-1 laptop: 25347bc74b3dSDaniel Drake - EC-driven system wakeups 25357feda8e9SDaniel Drake - Power button 25367bc74b3dSDaniel Drake - Ebook switch 25372cf2baeaSDaniel Drake - Lid switch 2538e1040ac6SDaniel Drake - AC adapter status updates 2539e1040ac6SDaniel Drake - Battery status updates 25407feda8e9SDaniel Drake 2541a0f30f59SDaniel Drakeconfig OLPC_XO15_SCI 2542a0f30f59SDaniel Drake bool "OLPC XO-1.5 SCI extras" 2543d8d01a63SDaniel Drake depends on OLPC && ACPI 2544d8d01a63SDaniel Drake select POWER_SUPPLY 2545a0f30f59SDaniel Drake ---help--- 2546a0f30f59SDaniel Drake Add support for SCI-based features of the OLPC XO-1.5 laptop: 2547a0f30f59SDaniel Drake - EC-driven system wakeups 2548a0f30f59SDaniel Drake - AC adapter status updates 2549a0f30f59SDaniel Drake - Battery status updates 2550e279b6c1SSam Ravnborg 2551d4f3e350SEd Wildgooseconfig ALIX 2552d4f3e350SEd Wildgoose bool "PCEngines ALIX System Support (LED setup)" 2553d4f3e350SEd Wildgoose select GPIOLIB 2554d4f3e350SEd Wildgoose ---help--- 2555d4f3e350SEd Wildgoose This option enables system support for the PCEngines ALIX. 2556d4f3e350SEd Wildgoose At present this just sets up LEDs for GPIO control on 2557d4f3e350SEd Wildgoose ALIX2/3/6 boards. However, other system specific setup should 2558d4f3e350SEd Wildgoose get added here. 2559d4f3e350SEd Wildgoose 2560d4f3e350SEd Wildgoose Note: You must still enable the drivers for GPIO and LED support 2561d4f3e350SEd Wildgoose (GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs 2562d4f3e350SEd Wildgoose 2563d4f3e350SEd Wildgoose Note: You have to set alix.force=1 for boards with Award BIOS. 2564d4f3e350SEd Wildgoose 2565da4e3302SPhilip Prindevilleconfig NET5501 2566da4e3302SPhilip Prindeville bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)" 2567da4e3302SPhilip Prindeville select GPIOLIB 2568da4e3302SPhilip Prindeville ---help--- 2569da4e3302SPhilip Prindeville This option enables system support for the Soekris Engineering net5501. 2570da4e3302SPhilip Prindeville 25713197059aSPhilip A. Prindevilleconfig GEOS 25723197059aSPhilip A. Prindeville bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)" 25733197059aSPhilip A. Prindeville select GPIOLIB 25743197059aSPhilip A. Prindeville depends on DMI 25753197059aSPhilip A. Prindeville ---help--- 25763197059aSPhilip A. Prindeville This option enables system support for the Traverse Technologies GEOS. 25773197059aSPhilip A. Prindeville 25787d029125SVivien Didelotconfig TS5500 25797d029125SVivien Didelot bool "Technologic Systems TS-5500 platform support" 25807d029125SVivien Didelot depends on MELAN 25817d029125SVivien Didelot select CHECK_SIGNATURE 25827d029125SVivien Didelot select NEW_LEDS 25837d029125SVivien Didelot select LEDS_CLASS 25847d029125SVivien Didelot ---help--- 25857d029125SVivien Didelot This option enables system support for the Technologic Systems TS-5500. 25867d029125SVivien Didelot 2587e279b6c1SSam Ravnborgendif # X86_32 2588e279b6c1SSam Ravnborg 258923ac4ae8SAndreas Herrmannconfig AMD_NB 2590e279b6c1SSam Ravnborg def_bool y 25910e152cd7SBorislav Petkov depends on CPU_SUP_AMD && PCI 2592e279b6c1SSam Ravnborg 2593e279b6c1SSam Ravnborgsource "drivers/pcmcia/Kconfig" 2594e279b6c1SSam Ravnborg 2595e279b6c1SSam Ravnborgsource "drivers/pci/hotplug/Kconfig" 2596e279b6c1SSam Ravnborg 2597388b78adSAlexandre Bounineconfig RAPIDIO 2598fdf90abcSAlexandre Bounine tristate "RapidIO support" 2599388b78adSAlexandre Bounine depends on PCI 2600388b78adSAlexandre Bounine default n 2601388b78adSAlexandre Bounine help 2602fdf90abcSAlexandre Bounine If enabled this option will include drivers and the core 2603388b78adSAlexandre Bounine infrastructure code to support RapidIO interconnect devices. 2604388b78adSAlexandre Bounine 2605388b78adSAlexandre Bouninesource "drivers/rapidio/Kconfig" 2606388b78adSAlexandre Bounine 2607e3263ab3SDavid Herrmannconfig X86_SYSFB 2608e3263ab3SDavid Herrmann bool "Mark VGA/VBE/EFI FB as generic system framebuffer" 2609e3263ab3SDavid Herrmann help 2610e3263ab3SDavid Herrmann Firmwares often provide initial graphics framebuffers so the BIOS, 2611e3263ab3SDavid Herrmann bootloader or kernel can show basic video-output during boot for 2612e3263ab3SDavid Herrmann user-guidance and debugging. Historically, x86 used the VESA BIOS 2613e3263ab3SDavid Herrmann Extensions and EFI-framebuffers for this, which are mostly limited 2614e3263ab3SDavid Herrmann to x86. 2615e3263ab3SDavid Herrmann This option, if enabled, marks VGA/VBE/EFI framebuffers as generic 2616e3263ab3SDavid Herrmann framebuffers so the new generic system-framebuffer drivers can be 2617e3263ab3SDavid Herrmann used on x86. If the framebuffer is not compatible with the generic 2618e3263ab3SDavid Herrmann modes, it is adverticed as fallback platform framebuffer so legacy 2619e3263ab3SDavid Herrmann drivers like efifb, vesafb and uvesafb can pick it up. 2620e3263ab3SDavid Herrmann If this option is not selected, all system framebuffers are always 2621e3263ab3SDavid Herrmann marked as fallback platform framebuffers as usual. 2622e3263ab3SDavid Herrmann 2623e3263ab3SDavid Herrmann Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will 2624e3263ab3SDavid Herrmann not be able to pick up generic system framebuffers if this option 2625e3263ab3SDavid Herrmann is selected. You are highly encouraged to enable simplefb as 2626e3263ab3SDavid Herrmann replacement if you select this option. simplefb can correctly deal 2627e3263ab3SDavid Herrmann with generic system framebuffers. But you should still keep vesafb 2628e3263ab3SDavid Herrmann and others enabled as fallback if a system framebuffer is 2629e3263ab3SDavid Herrmann incompatible with simplefb. 2630e3263ab3SDavid Herrmann 2631e3263ab3SDavid Herrmann If unsure, say Y. 2632e3263ab3SDavid Herrmann 2633e279b6c1SSam Ravnborgendmenu 2634e279b6c1SSam Ravnborg 2635e279b6c1SSam Ravnborg 2636e279b6c1SSam Ravnborgmenu "Executable file formats / Emulations" 2637e279b6c1SSam Ravnborg 2638e279b6c1SSam Ravnborgsource "fs/Kconfig.binfmt" 2639e279b6c1SSam Ravnborg 2640e279b6c1SSam Ravnborgconfig IA32_EMULATION 2641e279b6c1SSam Ravnborg bool "IA32 Emulation" 2642e279b6c1SSam Ravnborg depends on X86_64 2643d1603990SRandy Dunlap select BINFMT_ELF 2644a97f52e6SRoland McGrath select COMPAT_BINFMT_ELF 26453bead553SBrian Gerst select ARCH_WANT_OLD_COMPAT_IPC 26468f9ca475SIngo Molnar ---help--- 26475fd92e65SH. J. Lu Include code to run legacy 32-bit programs under a 26485fd92e65SH. J. Lu 64-bit kernel. You should likely turn this on, unless you're 26495fd92e65SH. J. Lu 100% sure that you don't have any 32-bit programs left. 2650e279b6c1SSam Ravnborg 2651e279b6c1SSam Ravnborgconfig IA32_AOUT 2652e279b6c1SSam Ravnborg tristate "IA32 a.out support" 26536b213e1bSDavid Woodhouse depends on IA32_EMULATION 26548f9ca475SIngo Molnar ---help--- 2655e279b6c1SSam Ravnborg Support old a.out binaries in the 32bit emulation. 2656e279b6c1SSam Ravnborg 26570bf62763SH. Peter Anvinconfig X86_X32 26586ea30386SKees Cook bool "x32 ABI for 64-bit mode" 26599b54050bSBrian Gerst depends on X86_64 26605fd92e65SH. J. Lu ---help--- 26615fd92e65SH. J. Lu Include code to run binaries for the x32 native 32-bit ABI 26625fd92e65SH. J. Lu for 64-bit processors. An x32 process gets access to the 26635fd92e65SH. J. Lu full 64-bit register file and wide data path while leaving 26645fd92e65SH. J. Lu pointers at 32 bits for smaller memory footprint. 26655fd92e65SH. J. Lu 26665fd92e65SH. J. Lu You will need a recent binutils (2.22 or later) with 26675fd92e65SH. J. Lu elf32_x86_64 support enabled to compile a kernel with this 26685fd92e65SH. J. Lu option set. 26695fd92e65SH. J. Lu 2670e279b6c1SSam Ravnborgconfig COMPAT 26713c2362e6SHarvey Harrison def_bool y 26720bf62763SH. Peter Anvin depends on IA32_EMULATION || X86_X32 2673e279b6c1SSam Ravnborg 26743120e25eSJan Beulichif COMPAT 2675e279b6c1SSam Ravnborgconfig COMPAT_FOR_U64_ALIGNMENT 26763120e25eSJan Beulich def_bool y 2677e279b6c1SSam Ravnborg 2678e279b6c1SSam Ravnborgconfig SYSVIPC_COMPAT 26793c2362e6SHarvey Harrison def_bool y 26803120e25eSJan Beulich depends on SYSVIPC 2681e279b6c1SSam Ravnborg 2682ee009e4aSDavid Howellsconfig KEYS_COMPAT 26833120e25eSJan Beulich def_bool y 26843120e25eSJan Beulich depends on KEYS 26853120e25eSJan Beulichendif 2686ee009e4aSDavid Howells 2687e279b6c1SSam Ravnborgendmenu 2688e279b6c1SSam Ravnborg 2689e279b6c1SSam Ravnborg 2690e5beae16SKeith Packardconfig HAVE_ATOMIC_IOMAP 2691e5beae16SKeith Packard def_bool y 2692e5beae16SKeith Packard depends on X86_32 2693e5beae16SKeith Packard 26944692d77fSAlessandro Rubiniconfig X86_DEV_DMA_OPS 26954692d77fSAlessandro Rubini bool 269683125a3aSAlessandro Rubini depends on X86_64 || STA2X11 26974692d77fSAlessandro Rubini 2698f7219a53SAlessandro Rubiniconfig X86_DMA_REMAP 2699f7219a53SAlessandro Rubini bool 270083125a3aSAlessandro Rubini depends on STA2X11 2701f7219a53SAlessandro Rubini 270293e5eaddSLi, Aubreyconfig PMC_ATOM 270393e5eaddSLi, Aubrey def_bool y 270493e5eaddSLi, Aubrey depends on PCI 270593e5eaddSLi, Aubrey 2706185a383aSKeith Buschconfig VMD 2707185a383aSKeith Busch depends on PCI_MSI 2708185a383aSKeith Busch tristate "Volume Management Device Driver" 2709185a383aSKeith Busch default N 2710185a383aSKeith Busch ---help--- 2711185a383aSKeith Busch Adds support for the Intel Volume Management Device (VMD). VMD is a 2712185a383aSKeith Busch secondary PCI host bridge that allows PCI Express root ports, 2713185a383aSKeith Busch and devices attached to them, to be removed from the default 2714185a383aSKeith Busch PCI domain and placed within the VMD domain. This provides 2715185a383aSKeith Busch more bus resources than are otherwise possible with a 2716185a383aSKeith Busch single domain. If you know your system provides one of these and 2717185a383aSKeith Busch has devices attached to it, say Y; if you are not sure, say N. 2718185a383aSKeith Busch 2719e279b6c1SSam Ravnborgsource "net/Kconfig" 2720e279b6c1SSam Ravnborg 2721e279b6c1SSam Ravnborgsource "drivers/Kconfig" 2722e279b6c1SSam Ravnborg 2723e279b6c1SSam Ravnborgsource "drivers/firmware/Kconfig" 2724e279b6c1SSam Ravnborg 2725e279b6c1SSam Ravnborgsource "fs/Kconfig" 2726e279b6c1SSam Ravnborg 2727e279b6c1SSam Ravnborgsource "arch/x86/Kconfig.debug" 2728e279b6c1SSam Ravnborg 2729e279b6c1SSam Ravnborgsource "security/Kconfig" 2730e279b6c1SSam Ravnborg 2731e279b6c1SSam Ravnborgsource "crypto/Kconfig" 2732e279b6c1SSam Ravnborg 2733edf88417SAvi Kivitysource "arch/x86/kvm/Kconfig" 2734edf88417SAvi Kivity 2735e279b6c1SSam Ravnborgsource "lib/Kconfig" 2736