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2912 lines
94 KiB
2912 lines
94 KiB
# SPDX-License-Identifier: GPL-2.0 |
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# Select 32 or 64 bit |
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config 64BIT |
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bool "64-bit kernel" if "$(ARCH)" = "x86" |
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default "$(ARCH)" != "i386" |
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help |
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Say yes to build a 64-bit kernel - formerly known as x86_64 |
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Say no to build a 32-bit kernel - formerly known as i386 |
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|
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config X86_32 |
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def_bool y |
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depends on !64BIT |
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# Options that are inherently 32-bit kernel only: |
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select ARCH_WANT_IPC_PARSE_VERSION |
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select CLKSRC_I8253 |
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select CLONE_BACKWARDS |
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select GENERIC_VDSO_32 |
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select HAVE_DEBUG_STACKOVERFLOW |
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select KMAP_LOCAL |
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select MODULES_USE_ELF_REL |
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select OLD_SIGACTION |
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select ARCH_SPLIT_ARG64 |
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config X86_64 |
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def_bool y |
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depends on 64BIT |
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# Options that are inherently 64-bit kernel only: |
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select ARCH_HAS_GIGANTIC_PAGE |
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select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 |
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select ARCH_USE_CMPXCHG_LOCKREF |
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select HAVE_ARCH_SOFT_DIRTY |
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select MODULES_USE_ELF_RELA |
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select NEED_DMA_MAP_STATE |
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select SWIOTLB |
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select ARCH_HAS_ELFCORE_COMPAT |
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|
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config FORCE_DYNAMIC_FTRACE |
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def_bool y |
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depends on X86_32 |
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depends on FUNCTION_TRACER |
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select DYNAMIC_FTRACE |
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help |
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We keep the static function tracing (!DYNAMIC_FTRACE) around |
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in order to test the non static function tracing in the |
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generic code, as other architectures still use it. But we |
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only need to keep it around for x86_64. No need to keep it |
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for x86_32. For x86_32, force DYNAMIC_FTRACE. |
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# |
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# Arch settings |
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# |
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# ( Note that options that are marked 'if X86_64' could in principle be |
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# ported to 32-bit as well. ) |
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# |
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config X86 |
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def_bool y |
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# |
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# Note: keep this list sorted alphabetically |
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# |
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select ACPI_LEGACY_TABLES_LOOKUP if ACPI |
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select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI |
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select ARCH_32BIT_OFF_T if X86_32 |
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select ARCH_CLOCKSOURCE_INIT |
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select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI |
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select ARCH_HAS_DEBUG_VIRTUAL |
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select ARCH_HAS_DEBUG_VM_PGTABLE if !X86_PAE |
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select ARCH_HAS_DEVMEM_IS_ALLOWED |
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select ARCH_HAS_EARLY_DEBUG if KGDB |
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select ARCH_HAS_ELF_RANDOMIZE |
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select ARCH_HAS_FAST_MULTIPLIER |
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select ARCH_HAS_FILTER_PGPROT |
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select ARCH_HAS_FORTIFY_SOURCE |
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select ARCH_HAS_GCOV_PROFILE_ALL |
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select ARCH_HAS_KCOV if X86_64 && STACK_VALIDATION |
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select ARCH_HAS_MEM_ENCRYPT |
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select ARCH_HAS_MEMBARRIER_SYNC_CORE |
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select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE |
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select ARCH_HAS_PMEM_API if X86_64 |
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select ARCH_HAS_PTE_DEVMAP if X86_64 |
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select ARCH_HAS_PTE_SPECIAL |
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select ARCH_HAS_UACCESS_FLUSHCACHE if X86_64 |
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select ARCH_HAS_COPY_MC if X86_64 |
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select ARCH_HAS_SET_MEMORY |
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select ARCH_HAS_SET_DIRECT_MAP |
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select ARCH_HAS_STRICT_KERNEL_RWX |
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select ARCH_HAS_STRICT_MODULE_RWX |
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select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE |
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select ARCH_HAS_SYSCALL_WRAPPER |
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select ARCH_HAS_UBSAN_SANITIZE_ALL |
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select ARCH_HAS_DEBUG_WX |
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select ARCH_HAVE_NMI_SAFE_CMPXCHG |
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select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI |
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select ARCH_MIGHT_HAVE_PC_PARPORT |
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select ARCH_MIGHT_HAVE_PC_SERIO |
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select ARCH_STACKWALK |
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select ARCH_SUPPORTS_ACPI |
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select ARCH_SUPPORTS_ATOMIC_RMW |
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select ARCH_SUPPORTS_DEBUG_PAGEALLOC |
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select ARCH_SUPPORTS_NUMA_BALANCING if X86_64 |
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select ARCH_SUPPORTS_KMAP_LOCAL_FORCE_MAP if NR_CPUS <= 4096 |
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select ARCH_SUPPORTS_LTO_CLANG if X86_64 |
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select ARCH_SUPPORTS_LTO_CLANG_THIN if X86_64 |
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select ARCH_USE_BUILTIN_BSWAP |
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select ARCH_USE_QUEUED_RWLOCKS |
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select ARCH_USE_QUEUED_SPINLOCKS |
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select ARCH_USE_SYM_ANNOTATIONS |
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select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH |
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select ARCH_WANT_DEFAULT_BPF_JIT if X86_64 |
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select ARCH_WANTS_DYNAMIC_TASK_STRUCT |
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select ARCH_WANT_HUGE_PMD_SHARE |
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select ARCH_WANT_LD_ORPHAN_WARN |
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select ARCH_WANTS_THP_SWAP if X86_64 |
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select BUILDTIME_TABLE_SORT |
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select CLKEVT_I8253 |
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select CLOCKSOURCE_VALIDATE_LAST_CYCLE |
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select CLOCKSOURCE_WATCHDOG |
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select DCACHE_WORD_ACCESS |
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select EDAC_ATOMIC_SCRUB |
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select EDAC_SUPPORT |
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select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC) |
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select GENERIC_CLOCKEVENTS_MIN_ADJUST |
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select GENERIC_CMOS_UPDATE |
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select GENERIC_CPU_AUTOPROBE |
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select GENERIC_CPU_VULNERABILITIES |
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select GENERIC_EARLY_IOREMAP |
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select GENERIC_ENTRY |
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select GENERIC_FIND_FIRST_BIT |
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select GENERIC_IOMAP |
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select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP |
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select GENERIC_IRQ_MATRIX_ALLOCATOR if X86_LOCAL_APIC |
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select GENERIC_IRQ_MIGRATION if SMP |
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select GENERIC_IRQ_PROBE |
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select GENERIC_IRQ_RESERVATION_MODE |
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select GENERIC_IRQ_SHOW |
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select GENERIC_PENDING_IRQ if SMP |
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select GENERIC_PTDUMP |
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select GENERIC_SMP_IDLE_THREAD |
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select GENERIC_STRNCPY_FROM_USER |
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select GENERIC_STRNLEN_USER |
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select GENERIC_TIME_VSYSCALL |
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select GENERIC_GETTIMEOFDAY |
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select GENERIC_VDSO_TIME_NS |
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select GUP_GET_PTE_LOW_HIGH if X86_PAE |
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select HARDIRQS_SW_RESEND |
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select HARDLOCKUP_CHECK_TIMESTAMP if X86_64 |
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select HAVE_ACPI_APEI if ACPI |
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select HAVE_ACPI_APEI_NMI if ACPI |
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select HAVE_ALIGNED_STRUCT_PAGE if SLUB |
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select HAVE_ARCH_AUDITSYSCALL |
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select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE |
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select HAVE_ARCH_JUMP_LABEL |
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select HAVE_ARCH_JUMP_LABEL_RELATIVE |
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select HAVE_ARCH_KASAN if X86_64 |
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select HAVE_ARCH_KASAN_VMALLOC if X86_64 |
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select HAVE_ARCH_KFENCE |
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select HAVE_ARCH_KGDB |
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select HAVE_ARCH_MMAP_RND_BITS if MMU |
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select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT |
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select HAVE_ARCH_COMPAT_MMAP_BASES if MMU && COMPAT |
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select HAVE_ARCH_PREL32_RELOCATIONS |
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select HAVE_ARCH_SECCOMP_FILTER |
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select HAVE_ARCH_THREAD_STRUCT_WHITELIST |
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select HAVE_ARCH_STACKLEAK |
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select HAVE_ARCH_TRACEHOOK |
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select HAVE_ARCH_TRANSPARENT_HUGEPAGE |
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select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64 |
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select HAVE_ARCH_USERFAULTFD_WP if X86_64 && USERFAULTFD |
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select HAVE_ARCH_VMAP_STACK if X86_64 |
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select HAVE_ARCH_WITHIN_STACK_FRAMES |
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select HAVE_ASM_MODVERSIONS |
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select HAVE_CMPXCHG_DOUBLE |
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select HAVE_CMPXCHG_LOCAL |
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select HAVE_CONTEXT_TRACKING if X86_64 |
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select HAVE_CONTEXT_TRACKING_OFFSTACK if HAVE_CONTEXT_TRACKING |
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select HAVE_C_RECORDMCOUNT |
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select HAVE_OBJTOOL_MCOUNT if STACK_VALIDATION |
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select HAVE_DEBUG_KMEMLEAK |
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select HAVE_DMA_CONTIGUOUS |
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select HAVE_DYNAMIC_FTRACE |
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select HAVE_DYNAMIC_FTRACE_WITH_REGS |
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select HAVE_DYNAMIC_FTRACE_WITH_ARGS if X86_64 |
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select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS |
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select HAVE_EBPF_JIT |
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select HAVE_EFFICIENT_UNALIGNED_ACCESS |
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select HAVE_EISA |
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select HAVE_EXIT_THREAD |
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select HAVE_FAST_GUP |
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select HAVE_FENTRY if X86_64 || DYNAMIC_FTRACE |
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select HAVE_FTRACE_MCOUNT_RECORD |
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select HAVE_FUNCTION_GRAPH_TRACER |
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select HAVE_FUNCTION_TRACER |
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select HAVE_GCC_PLUGINS |
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select HAVE_HW_BREAKPOINT |
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select HAVE_IDE |
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select HAVE_IOREMAP_PROT |
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select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64 |
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select HAVE_IRQ_TIME_ACCOUNTING |
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select HAVE_KERNEL_BZIP2 |
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select HAVE_KERNEL_GZIP |
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select HAVE_KERNEL_LZ4 |
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select HAVE_KERNEL_LZMA |
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select HAVE_KERNEL_LZO |
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select HAVE_KERNEL_XZ |
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select HAVE_KERNEL_ZSTD |
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select HAVE_KPROBES |
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select HAVE_KPROBES_ON_FTRACE |
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select HAVE_FUNCTION_ERROR_INJECTION |
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select HAVE_KRETPROBES |
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select HAVE_KVM |
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select HAVE_LIVEPATCH if X86_64 |
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select HAVE_MIXED_BREAKPOINTS_REGS |
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select HAVE_MOD_ARCH_SPECIFIC |
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select HAVE_MOVE_PMD |
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select HAVE_MOVE_PUD |
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select HAVE_NMI |
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select HAVE_OPTPROBES |
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select HAVE_PCSPKR_PLATFORM |
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select HAVE_PERF_EVENTS |
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select HAVE_PERF_EVENTS_NMI |
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select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && HAVE_PERF_EVENTS_NMI |
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select HAVE_PCI |
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select HAVE_PERF_REGS |
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select HAVE_PERF_USER_STACK_DUMP |
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select MMU_GATHER_RCU_TABLE_FREE if PARAVIRT |
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select HAVE_POSIX_CPU_TIMERS_TASK_WORK |
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select HAVE_REGS_AND_STACK_ACCESS_API |
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select HAVE_RELIABLE_STACKTRACE if X86_64 && (UNWINDER_FRAME_POINTER || UNWINDER_ORC) && STACK_VALIDATION |
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select HAVE_FUNCTION_ARG_ACCESS_API |
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select HAVE_SOFTIRQ_ON_OWN_STACK |
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select HAVE_STACKPROTECTOR if CC_HAS_SANE_STACKPROTECTOR |
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select HAVE_STACK_VALIDATION if X86_64 |
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select HAVE_STATIC_CALL |
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select HAVE_STATIC_CALL_INLINE if HAVE_STACK_VALIDATION |
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select HAVE_PREEMPT_DYNAMIC |
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select HAVE_RSEQ |
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select HAVE_SYSCALL_TRACEPOINTS |
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select HAVE_UNSTABLE_SCHED_CLOCK |
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select HAVE_USER_RETURN_NOTIFIER |
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select HAVE_GENERIC_VDSO |
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select HOTPLUG_SMT if SMP |
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select IRQ_FORCED_THREADING |
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select NEED_SG_DMA_LENGTH |
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select PCI_DOMAINS if PCI |
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select PCI_LOCKLESS_CONFIG if PCI |
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select PERF_EVENTS |
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select RTC_LIB |
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select RTC_MC146818_LIB |
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select SPARSE_IRQ |
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select SRCU |
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select STACK_VALIDATION if HAVE_STACK_VALIDATION && (HAVE_STATIC_CALL_INLINE || RETPOLINE) |
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select SYSCTL_EXCEPTION_TRACE |
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select THREAD_INFO_IN_TASK |
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select USER_STACKTRACE_SUPPORT |
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select VIRT_TO_BUS |
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select HAVE_ARCH_KCSAN if X86_64 |
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select X86_FEATURE_NAMES if PROC_FS |
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select PROC_PID_ARCH_STATUS if PROC_FS |
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imply IMA_SECURE_AND_OR_TRUSTED_BOOT if EFI |
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|
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config INSTRUCTION_DECODER |
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def_bool y |
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depends on KPROBES || PERF_EVENTS || UPROBES |
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config OUTPUT_FORMAT |
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string |
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default "elf32-i386" if X86_32 |
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default "elf64-x86-64" if X86_64 |
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config LOCKDEP_SUPPORT |
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def_bool y |
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config STACKTRACE_SUPPORT |
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def_bool y |
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config MMU |
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def_bool y |
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config ARCH_MMAP_RND_BITS_MIN |
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default 28 if 64BIT |
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default 8 |
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config ARCH_MMAP_RND_BITS_MAX |
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default 32 if 64BIT |
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default 16 |
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config ARCH_MMAP_RND_COMPAT_BITS_MIN |
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default 8 |
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config ARCH_MMAP_RND_COMPAT_BITS_MAX |
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default 16 |
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config SBUS |
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bool |
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config GENERIC_ISA_DMA |
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def_bool y |
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depends on ISA_DMA_API |
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config GENERIC_BUG |
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def_bool y |
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depends on BUG |
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select GENERIC_BUG_RELATIVE_POINTERS if X86_64 |
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|
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config GENERIC_BUG_RELATIVE_POINTERS |
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bool |
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config ARCH_MAY_HAVE_PC_FDC |
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def_bool y |
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depends on ISA_DMA_API |
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|
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config GENERIC_CALIBRATE_DELAY |
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def_bool y |
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config ARCH_HAS_CPU_RELAX |
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def_bool y |
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config ARCH_HAS_CACHE_LINE_SIZE |
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def_bool y |
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config ARCH_HAS_FILTER_PGPROT |
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def_bool y |
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config HAVE_SETUP_PER_CPU_AREA |
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def_bool y |
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config NEED_PER_CPU_EMBED_FIRST_CHUNK |
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def_bool y |
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config NEED_PER_CPU_PAGE_FIRST_CHUNK |
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def_bool y |
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config ARCH_HIBERNATION_POSSIBLE |
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def_bool y |
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config ARCH_SUSPEND_POSSIBLE |
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def_bool y |
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config ARCH_WANT_GENERAL_HUGETLB |
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def_bool y |
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config ZONE_DMA32 |
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def_bool y if X86_64 |
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config AUDIT_ARCH |
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def_bool y if X86_64 |
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|
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config KASAN_SHADOW_OFFSET |
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hex |
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depends on KASAN |
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default 0xdffffc0000000000 |
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|
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config HAVE_INTEL_TXT |
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def_bool y |
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depends on INTEL_IOMMU && ACPI |
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config X86_32_SMP |
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def_bool y |
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depends on X86_32 && SMP |
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|
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config X86_64_SMP |
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def_bool y |
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depends on X86_64 && SMP |
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config X86_32_LAZY_GS |
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def_bool y |
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depends on X86_32 && !STACKPROTECTOR |
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config ARCH_SUPPORTS_UPROBES |
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def_bool y |
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config FIX_EARLYCON_MEM |
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def_bool y |
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config DYNAMIC_PHYSICAL_MASK |
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bool |
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|
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config PGTABLE_LEVELS |
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int |
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default 5 if X86_5LEVEL |
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default 4 if X86_64 |
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default 3 if X86_PAE |
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default 2 |
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|
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config CC_HAS_SANE_STACKPROTECTOR |
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bool |
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default $(success,$(srctree)/scripts/gcc-x86_64-has-stack-protector.sh $(CC)) if 64BIT |
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default $(success,$(srctree)/scripts/gcc-x86_32-has-stack-protector.sh $(CC)) |
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help |
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We have to make sure stack protector is unconditionally disabled if |
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the compiler produces broken code. |
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|
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menu "Processor type and features" |
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|
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config ZONE_DMA |
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bool "DMA memory allocation support" if EXPERT |
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default y |
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help |
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DMA memory allocation support allows devices with less than 32-bit |
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addressing to allocate within the first 16MB of address space. |
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Disable if no such devices will be used. |
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|
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If unsure, say Y. |
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|
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config SMP |
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bool "Symmetric multi-processing support" |
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help |
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This enables support for systems with more than one CPU. If you have |
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a system with only one CPU, say N. If you have a system with more |
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than one CPU, say Y. |
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|
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If you say N here, the kernel will run on uni- and multiprocessor |
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machines, but will use only one CPU of a multiprocessor machine. If |
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you say Y here, the kernel will run on many, but not all, |
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uniprocessor machines. On a uniprocessor machine, the kernel |
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will run faster if you say N here. |
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|
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Note that if you say Y here and choose architecture "586" or |
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"Pentium" under "Processor family", the kernel will not work on 486 |
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architectures. Similarly, multiprocessor kernels for the "PPro" |
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architecture may not work on all Pentium based boards. |
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|
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People using multiprocessor machines who say Y here should also say |
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Y to "Enhanced Real Time Clock Support", below. The "Advanced Power |
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Management" code will be disabled if you say Y here. |
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|
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See also <file:Documentation/x86/i386/IO-APIC.rst>, |
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<file:Documentation/admin-guide/lockup-watchdogs.rst> and the SMP-HOWTO available at |
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<http://www.tldp.org/docs.html#howto>. |
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|
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If you don't know what to do here, say N. |
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|
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config X86_FEATURE_NAMES |
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bool "Processor feature human-readable names" if EMBEDDED |
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default y |
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help |
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This option compiles in a table of x86 feature bits and corresponding |
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names. This is required to support /proc/cpuinfo and a few kernel |
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messages. You can disable this to save space, at the expense of |
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making those few kernel messages show numeric feature bits instead. |
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|
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If in doubt, say Y. |
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|
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config X86_X2APIC |
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bool "Support x2apic" |
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depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST) |
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help |
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This enables x2apic support on CPUs that have this feature. |
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|
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This allows 32-bit apic IDs (so it can support very large systems), |
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and accesses the local apic via MSRs not via mmio. |
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|
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If you don't know what to do here, say N. |
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|
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config X86_MPPARSE |
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bool "Enable MPS table" if ACPI |
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default y |
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depends on X86_LOCAL_APIC |
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help |
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For old smp systems that do not have proper acpi support. Newer systems |
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(esp with 64bit cpus) with acpi support, MADT and DSDT will override it |
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|
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config GOLDFISH |
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def_bool y |
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depends on X86_GOLDFISH |
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|
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config RETPOLINE |
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bool "Avoid speculative indirect branches in kernel" |
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default y |
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help |
|
Compile kernel with the retpoline compiler options to guard against |
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kernel-to-user data leaks by avoiding speculative indirect |
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branches. Requires a compiler with -mindirect-branch=thunk-extern |
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support for full protection. The kernel may run slower. |
|
|
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config X86_CPU_RESCTRL |
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bool "x86 CPU resource control support" |
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depends on X86 && (CPU_SUP_INTEL || CPU_SUP_AMD) |
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select KERNFS |
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select PROC_CPU_RESCTRL if PROC_FS |
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help |
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Enable x86 CPU resource control support. |
|
|
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Provide support for the allocation and monitoring of system resources |
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usage by the CPU. |
|
|
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Intel calls this Intel Resource Director Technology |
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(Intel(R) RDT). More information about RDT can be found in the |
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Intel x86 Architecture Software Developer Manual. |
|
|
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AMD calls this AMD Platform Quality of Service (AMD QoS). |
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More information about AMD QoS can be found in the AMD64 Technology |
|
Platform Quality of Service Extensions manual. |
|
|
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Say N if unsure. |
|
|
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if X86_32 |
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config X86_BIGSMP |
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bool "Support for big SMP systems with more than 8 CPUs" |
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depends on SMP |
|
help |
|
This option is needed for the systems that have more than 8 CPUs. |
|
|
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config X86_EXTENDED_PLATFORM |
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bool "Support for extended (non-PC) x86 platforms" |
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default y |
|
help |
|
If you disable this option then the kernel will only support |
|
standard PC platforms. (which covers the vast majority of |
|
systems out there.) |
|
|
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If you enable this option then you'll be able to select support |
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for the following (non-PC) 32 bit x86 platforms: |
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Goldfish (Android emulator) |
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AMD Elan |
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RDC R-321x SoC |
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SGI 320/540 (Visual Workstation) |
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STA2X11-based (e.g. Northville) |
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Moorestown MID devices |
|
|
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If you have one of these systems, or if you want to build a |
|
generic distribution kernel, say Y here - otherwise say N. |
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endif |
|
|
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if X86_64 |
|
config X86_EXTENDED_PLATFORM |
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bool "Support for extended (non-PC) x86 platforms" |
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default y |
|
help |
|
If you disable this option then the kernel will only support |
|
standard PC platforms. (which covers the vast majority of |
|
systems out there.) |
|
|
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If you enable this option then you'll be able to select support |
|
for the following (non-PC) 64 bit x86 platforms: |
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Numascale NumaChip |
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ScaleMP vSMP |
|
SGI Ultraviolet |
|
|
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If you have one of these systems, or if you want to build a |
|
generic distribution kernel, say Y here - otherwise say N. |
|
endif |
|
# This is an alphabetically sorted list of 64 bit extended platforms |
|
# Please maintain the alphabetic order if and when there are additions |
|
config X86_NUMACHIP |
|
bool "Numascale NumaChip" |
|
depends on X86_64 |
|
depends on X86_EXTENDED_PLATFORM |
|
depends on NUMA |
|
depends on SMP |
|
depends on X86_X2APIC |
|
depends on PCI_MMCONFIG |
|
help |
|
Adds support for Numascale NumaChip large-SMP systems. Needed to |
|
enable more than ~168 cores. |
|
If you don't have one of these, you should say N here. |
|
|
|
config X86_VSMP |
|
bool "ScaleMP vSMP" |
|
select HYPERVISOR_GUEST |
|
select PARAVIRT |
|
depends on X86_64 && PCI |
|
depends on X86_EXTENDED_PLATFORM |
|
depends on SMP |
|
help |
|
Support for ScaleMP vSMP systems. Say 'Y' here if this kernel is |
|
supposed to run on these EM64T-based machines. Only choose this option |
|
if you have one of these machines. |
|
|
|
config X86_UV |
|
bool "SGI Ultraviolet" |
|
depends on X86_64 |
|
depends on X86_EXTENDED_PLATFORM |
|
depends on NUMA |
|
depends on EFI |
|
depends on KEXEC_CORE |
|
depends on X86_X2APIC |
|
depends on PCI |
|
help |
|
This option is needed in order to support SGI Ultraviolet systems. |
|
If you don't have one of these, you should say N here. |
|
|
|
# Following is an alphabetically sorted list of 32 bit extended platforms |
|
# Please maintain the alphabetic order if and when there are additions |
|
|
|
config X86_GOLDFISH |
|
bool "Goldfish (Virtual Platform)" |
|
depends on X86_EXTENDED_PLATFORM |
|
help |
|
Enable support for the Goldfish virtual platform used primarily |
|
for Android development. Unless you are building for the Android |
|
Goldfish emulator say N here. |
|
|
|
config X86_INTEL_CE |
|
bool "CE4100 TV platform" |
|
depends on PCI |
|
depends on PCI_GODIRECT |
|
depends on X86_IO_APIC |
|
depends on X86_32 |
|
depends on X86_EXTENDED_PLATFORM |
|
select X86_REBOOTFIXUPS |
|
select OF |
|
select OF_EARLY_FLATTREE |
|
help |
|
Select for the Intel CE media processor (CE4100) SOC. |
|
This option compiles in support for the CE4100 SOC for settop |
|
boxes and media devices. |
|
|
|
config X86_INTEL_MID |
|
bool "Intel MID platform support" |
|
depends on X86_EXTENDED_PLATFORM |
|
depends on X86_PLATFORM_DEVICES |
|
depends on PCI |
|
depends on X86_64 || (PCI_GOANY && X86_32) |
|
depends on X86_IO_APIC |
|
select I2C |
|
select DW_APB_TIMER |
|
select APB_TIMER |
|
select INTEL_SCU_PCI |
|
select MFD_INTEL_MSIC |
|
help |
|
Select to build a kernel capable of supporting Intel MID (Mobile |
|
Internet Device) platform systems which do not have the PCI legacy |
|
interfaces. If you are building for a PC class system say N here. |
|
|
|
Intel MID platforms are based on an Intel processor and chipset which |
|
consume less power than most of the x86 derivatives. |
|
|
|
config X86_INTEL_QUARK |
|
bool "Intel Quark platform support" |
|
depends on X86_32 |
|
depends on X86_EXTENDED_PLATFORM |
|
depends on X86_PLATFORM_DEVICES |
|
depends on X86_TSC |
|
depends on PCI |
|
depends on PCI_GOANY |
|
depends on X86_IO_APIC |
|
select IOSF_MBI |
|
select INTEL_IMR |
|
select COMMON_CLK |
|
help |
|
Select to include support for Quark X1000 SoC. |
|
Say Y here if you have a Quark based system such as the Arduino |
|
compatible Intel Galileo. |
|
|
|
config X86_INTEL_LPSS |
|
bool "Intel Low Power Subsystem Support" |
|
depends on X86 && ACPI && PCI |
|
select COMMON_CLK |
|
select PINCTRL |
|
select IOSF_MBI |
|
help |
|
Select to build support for Intel Low Power Subsystem such as |
|
found on Intel Lynxpoint PCH. Selecting this option enables |
|
things like clock tree (common clock framework) and pincontrol |
|
which are needed by the LPSS peripheral drivers. |
|
|
|
config X86_AMD_PLATFORM_DEVICE |
|
bool "AMD ACPI2Platform devices support" |
|
depends on ACPI |
|
select COMMON_CLK |
|
select PINCTRL |
|
help |
|
Select to interpret AMD specific ACPI device to platform device |
|
such as I2C, UART, GPIO found on AMD Carrizo and later chipsets. |
|
I2C and UART depend on COMMON_CLK to set clock. GPIO driver is |
|
implemented under PINCTRL subsystem. |
|
|
|
config IOSF_MBI |
|
tristate "Intel SoC IOSF Sideband support for SoC platforms" |
|
depends on PCI |
|
help |
|
This option enables sideband register access support for Intel SoC |
|
platforms. On these platforms the IOSF sideband is used in lieu of |
|
MSR's for some register accesses, mostly but not limited to thermal |
|
and power. Drivers may query the availability of this device to |
|
determine if they need the sideband in order to work on these |
|
platforms. The sideband is available on the following SoC products. |
|
This list is not meant to be exclusive. |
|
- BayTrail |
|
- Braswell |
|
- Quark |
|
|
|
You should say Y if you are running a kernel on one of these SoC's. |
|
|
|
config IOSF_MBI_DEBUG |
|
bool "Enable IOSF sideband access through debugfs" |
|
depends on IOSF_MBI && DEBUG_FS |
|
help |
|
Select this option to expose the IOSF sideband access registers (MCR, |
|
MDR, MCRX) through debugfs to write and read register information from |
|
different units on the SoC. This is most useful for obtaining device |
|
state information for debug and analysis. As this is a general access |
|
mechanism, users of this option would have specific knowledge of the |
|
device they want to access. |
|
|
|
If you don't require the option or are in doubt, say N. |
|
|
|
config X86_RDC321X |
|
bool "RDC R-321x SoC" |
|
depends on X86_32 |
|
depends on X86_EXTENDED_PLATFORM |
|
select M486 |
|
select X86_REBOOTFIXUPS |
|
help |
|
This option is needed for RDC R-321x system-on-chip, also known |
|
as R-8610-(G). |
|
If you don't have one of these chips, you should say N here. |
|
|
|
config X86_32_NON_STANDARD |
|
bool "Support non-standard 32-bit SMP architectures" |
|
depends on X86_32 && SMP |
|
depends on X86_EXTENDED_PLATFORM |
|
help |
|
This option compiles in the bigsmp and STA2X11 default |
|
subarchitectures. It is intended for a generic binary |
|
kernel. If you select them all, kernel will probe it one by |
|
one and will fallback to default. |
|
|
|
# Alphabetically sorted list of Non standard 32 bit platforms |
|
|
|
config X86_SUPPORTS_MEMORY_FAILURE |
|
def_bool y |
|
# MCE code calls memory_failure(): |
|
depends on X86_MCE |
|
# On 32-bit this adds too big of NODES_SHIFT and we run out of page flags: |
|
# On 32-bit SPARSEMEM adds too big of SECTIONS_WIDTH: |
|
depends on X86_64 || !SPARSEMEM |
|
select ARCH_SUPPORTS_MEMORY_FAILURE |
|
|
|
config STA2X11 |
|
bool "STA2X11 Companion Chip Support" |
|
depends on X86_32_NON_STANDARD && PCI |
|
select SWIOTLB |
|
select MFD_STA2X11 |
|
select GPIOLIB |
|
help |
|
This adds support for boards based on the STA2X11 IO-Hub, |
|
a.k.a. "ConneXt". The chip is used in place of the standard |
|
PC chipset, so all "standard" peripherals are missing. If this |
|
option is selected the kernel will still be able to boot on |
|
standard PC machines. |
|
|
|
config X86_32_IRIS |
|
tristate "Eurobraille/Iris poweroff module" |
|
depends on X86_32 |
|
help |
|
The Iris machines from EuroBraille do not have APM or ACPI support |
|
to shut themselves down properly. A special I/O sequence is |
|
needed to do so, which is what this module does at |
|
kernel shutdown. |
|
|
|
This is only for Iris machines from EuroBraille. |
|
|
|
If unused, say N. |
|
|
|
config SCHED_OMIT_FRAME_POINTER |
|
def_bool y |
|
prompt "Single-depth WCHAN output" |
|
depends on X86 |
|
help |
|
Calculate simpler /proc/<PID>/wchan values. If this option |
|
is disabled then wchan values will recurse back to the |
|
caller function. This provides more accurate wchan values, |
|
at the expense of slightly more scheduling overhead. |
|
|
|
If in doubt, say "Y". |
|
|
|
menuconfig HYPERVISOR_GUEST |
|
bool "Linux guest support" |
|
help |
|
Say Y here to enable options for running Linux under various hyper- |
|
visors. This option enables basic hypervisor detection and platform |
|
setup. |
|
|
|
If you say N, all options in this submenu will be skipped and |
|
disabled, and Linux guest support won't be built in. |
|
|
|
if HYPERVISOR_GUEST |
|
|
|
config PARAVIRT |
|
bool "Enable paravirtualization code" |
|
help |
|
This changes the kernel so it can modify itself when it is run |
|
under a hypervisor, potentially improving performance significantly |
|
over full virtualization. However, when run without a hypervisor |
|
the kernel is theoretically slower and slightly larger. |
|
|
|
config PARAVIRT_XXL |
|
bool |
|
|
|
config PARAVIRT_DEBUG |
|
bool "paravirt-ops debugging" |
|
depends on PARAVIRT && DEBUG_KERNEL |
|
help |
|
Enable to debug paravirt_ops internals. Specifically, BUG if |
|
a paravirt_op is missing when it is called. |
|
|
|
config PARAVIRT_SPINLOCKS |
|
bool "Paravirtualization layer for spinlocks" |
|
depends on PARAVIRT && SMP |
|
help |
|
Paravirtualized spinlocks allow a pvops backend to replace the |
|
spinlock implementation with something virtualization-friendly |
|
(for example, block the virtual CPU rather than spinning). |
|
|
|
It has a minimal impact on native kernels and gives a nice performance |
|
benefit on paravirtualized KVM / Xen kernels. |
|
|
|
If you are unsure how to answer this question, answer Y. |
|
|
|
config X86_HV_CALLBACK_VECTOR |
|
def_bool n |
|
|
|
source "arch/x86/xen/Kconfig" |
|
|
|
config KVM_GUEST |
|
bool "KVM Guest support (including kvmclock)" |
|
depends on PARAVIRT |
|
select PARAVIRT_CLOCK |
|
select ARCH_CPUIDLE_HALTPOLL |
|
select X86_HV_CALLBACK_VECTOR |
|
default y |
|
help |
|
This option enables various optimizations for running under the KVM |
|
hypervisor. It includes a paravirtualized clock, so that instead |
|
of relying on a PIT (or probably other) emulation by the |
|
underlying device model, the host provides the guest with |
|
timing infrastructure such as time of day, and system time |
|
|
|
config ARCH_CPUIDLE_HALTPOLL |
|
def_bool n |
|
prompt "Disable host haltpoll when loading haltpoll driver" |
|
help |
|
If virtualized under KVM, disable host haltpoll. |
|
|
|
config PVH |
|
bool "Support for running PVH guests" |
|
help |
|
This option enables the PVH entry point for guest virtual machines |
|
as specified in the x86/HVM direct boot ABI. |
|
|
|
config PARAVIRT_TIME_ACCOUNTING |
|
bool "Paravirtual steal time accounting" |
|
depends on PARAVIRT |
|
help |
|
Select this option to enable fine granularity task steal time |
|
accounting. Time spent executing other tasks in parallel with |
|
the current vCPU is discounted from the vCPU power. To account for |
|
that, there can be a small performance impact. |
|
|
|
If in doubt, say N here. |
|
|
|
config PARAVIRT_CLOCK |
|
bool |
|
|
|
config JAILHOUSE_GUEST |
|
bool "Jailhouse non-root cell support" |
|
depends on X86_64 && PCI |
|
select X86_PM_TIMER |
|
help |
|
This option allows to run Linux as guest in a Jailhouse non-root |
|
cell. You can leave this option disabled if you only want to start |
|
Jailhouse and run Linux afterwards in the root cell. |
|
|
|
config ACRN_GUEST |
|
bool "ACRN Guest support" |
|
depends on X86_64 |
|
select X86_HV_CALLBACK_VECTOR |
|
help |
|
This option allows to run Linux as guest in the ACRN hypervisor. ACRN is |
|
a flexible, lightweight reference open-source hypervisor, built with |
|
real-time and safety-criticality in mind. It is built for embedded |
|
IOT with small footprint and real-time features. More details can be |
|
found in https://projectacrn.org/. |
|
|
|
endif #HYPERVISOR_GUEST |
|
|
|
source "arch/x86/Kconfig.cpu" |
|
|
|
config HPET_TIMER |
|
def_bool X86_64 |
|
prompt "HPET Timer Support" if X86_32 |
|
help |
|
Use the IA-PC HPET (High Precision Event Timer) to manage |
|
time in preference to the PIT and RTC, if a HPET is |
|
present. |
|
HPET is the next generation timer replacing legacy 8254s. |
|
The HPET provides a stable time base on SMP |
|
systems, unlike the TSC, but it is more expensive to access, |
|
as it is off-chip. The interface used is documented |
|
in the HPET spec, revision 1. |
|
|
|
You can safely choose Y here. However, HPET will only be |
|
activated if the platform and the BIOS support this feature. |
|
Otherwise the 8254 will be used for timing services. |
|
|
|
Choose N to continue using the legacy 8254 timer. |
|
|
|
config HPET_EMULATE_RTC |
|
def_bool y |
|
depends on HPET_TIMER && (RTC_DRV_CMOS=m || RTC_DRV_CMOS=y) |
|
|
|
# Mark as expert because too many people got it wrong. |
|
# The code disables itself when not needed. |
|
config DMI |
|
default y |
|
select DMI_SCAN_MACHINE_NON_EFI_FALLBACK |
|
bool "Enable DMI scanning" if EXPERT |
|
help |
|
Enabled scanning of DMI to identify machine quirks. Say Y |
|
here unless you have verified that your setup is not |
|
affected by entries in the DMI blacklist. Required by PNP |
|
BIOS code. |
|
|
|
config GART_IOMMU |
|
bool "Old AMD GART IOMMU support" |
|
select DMA_OPS |
|
select IOMMU_HELPER |
|
select SWIOTLB |
|
depends on X86_64 && PCI && AMD_NB |
|
help |
|
Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron |
|
GART based hardware IOMMUs. |
|
|
|
The GART supports full DMA access for devices with 32-bit access |
|
limitations, on systems with more than 3 GB. This is usually needed |
|
for USB, sound, many IDE/SATA chipsets and some other devices. |
|
|
|
Newer systems typically have a modern AMD IOMMU, supported via |
|
the CONFIG_AMD_IOMMU=y config option. |
|
|
|
In normal configurations this driver is only active when needed: |
|
there's more than 3 GB of memory and the system contains a |
|
32-bit limited device. |
|
|
|
If unsure, say Y. |
|
|
|
config MAXSMP |
|
bool "Enable Maximum number of SMP Processors and NUMA Nodes" |
|
depends on X86_64 && SMP && DEBUG_KERNEL |
|
select CPUMASK_OFFSTACK |
|
help |
|
Enable maximum number of CPUS and NUMA Nodes for this architecture. |
|
If unsure, say N. |
|
|
|
# |
|
# The maximum number of CPUs supported: |
|
# |
|
# The main config value is NR_CPUS, which defaults to NR_CPUS_DEFAULT, |
|
# and which can be configured interactively in the |
|
# [NR_CPUS_RANGE_BEGIN ... NR_CPUS_RANGE_END] range. |
|
# |
|
# The ranges are different on 32-bit and 64-bit kernels, depending on |
|
# hardware capabilities and scalability features of the kernel. |
|
# |
|
# ( If MAXSMP is enabled we just use the highest possible value and disable |
|
# interactive configuration. ) |
|
# |
|
|
|
config NR_CPUS_RANGE_BEGIN |
|
int |
|
default NR_CPUS_RANGE_END if MAXSMP |
|
default 1 if !SMP |
|
default 2 |
|
|
|
config NR_CPUS_RANGE_END |
|
int |
|
depends on X86_32 |
|
default 64 if SMP && X86_BIGSMP |
|
default 8 if SMP && !X86_BIGSMP |
|
default 1 if !SMP |
|
|
|
config NR_CPUS_RANGE_END |
|
int |
|
depends on X86_64 |
|
default 8192 if SMP && CPUMASK_OFFSTACK |
|
default 512 if SMP && !CPUMASK_OFFSTACK |
|
default 1 if !SMP |
|
|
|
config NR_CPUS_DEFAULT |
|
int |
|
depends on X86_32 |
|
default 32 if X86_BIGSMP |
|
default 8 if SMP |
|
default 1 if !SMP |
|
|
|
config NR_CPUS_DEFAULT |
|
int |
|
depends on X86_64 |
|
default 8192 if MAXSMP |
|
default 64 if SMP |
|
default 1 if !SMP |
|
|
|
config NR_CPUS |
|
int "Maximum number of CPUs" if SMP && !MAXSMP |
|
range NR_CPUS_RANGE_BEGIN NR_CPUS_RANGE_END |
|
default NR_CPUS_DEFAULT |
|
help |
|
This allows you to specify the maximum number of CPUs which this |
|
kernel will support. If CPUMASK_OFFSTACK is enabled, the maximum |
|
supported value is 8192, otherwise the maximum value is 512. The |
|
minimum value which makes sense is 2. |
|
|
|
This is purely to save memory: each supported CPU adds about 8KB |
|
to the kernel image. |
|
|
|
config SCHED_SMT |
|
def_bool y if SMP |
|
|
|
config SCHED_MC |
|
def_bool y |
|
prompt "Multi-core scheduler support" |
|
depends on SMP |
|
help |
|
Multi-core scheduler support improves the CPU scheduler's decision |
|
making when dealing with multi-core CPU chips at a cost of slightly |
|
increased overhead in some places. If unsure say N here. |
|
|
|
config SCHED_MC_PRIO |
|
bool "CPU core priorities scheduler support" |
|
depends on SCHED_MC && CPU_SUP_INTEL |
|
select X86_INTEL_PSTATE |
|
select CPU_FREQ |
|
default y |
|
help |
|
Intel Turbo Boost Max Technology 3.0 enabled CPUs have a |
|
core ordering determined at manufacturing time, which allows |
|
certain cores to reach higher turbo frequencies (when running |
|
single threaded workloads) than others. |
|
|
|
Enabling this kernel feature teaches the scheduler about |
|
the TBM3 (aka ITMT) priority order of the CPU cores and adjusts the |
|
scheduler's CPU selection logic accordingly, so that higher |
|
overall system performance can be achieved. |
|
|
|
This feature will have no effect on CPUs without this feature. |
|
|
|
If unsure say Y here. |
|
|
|
config UP_LATE_INIT |
|
def_bool y |
|
depends on !SMP && X86_LOCAL_APIC |
|
|
|
config X86_UP_APIC |
|
bool "Local APIC support on uniprocessors" if !PCI_MSI |
|
default PCI_MSI |
|
depends on X86_32 && !SMP && !X86_32_NON_STANDARD |
|
help |
|
A local APIC (Advanced Programmable Interrupt Controller) is an |
|
integrated interrupt controller in the CPU. If you have a single-CPU |
|
system which has a processor with a local APIC, you can say Y here to |
|
enable and use it. If you say Y here even though your machine doesn't |
|
have a local APIC, then the kernel will still run with no slowdown at |
|
all. The local APIC supports CPU-generated self-interrupts (timer, |
|
performance counters), and the NMI watchdog which detects hard |
|
lockups. |
|
|
|
config X86_UP_IOAPIC |
|
bool "IO-APIC support on uniprocessors" |
|
depends on X86_UP_APIC |
|
help |
|
An IO-APIC (I/O Advanced Programmable Interrupt Controller) is an |
|
SMP-capable replacement for PC-style interrupt controllers. Most |
|
SMP systems and many recent uniprocessor systems have one. |
|
|
|
If you have a single-CPU system with an IO-APIC, you can say Y here |
|
to use it. If you say Y here even though your machine doesn't have |
|
an IO-APIC, then the kernel will still run with no slowdown at all. |
|
|
|
config X86_LOCAL_APIC |
|
def_bool y |
|
depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI |
|
select IRQ_DOMAIN_HIERARCHY |
|
select PCI_MSI_IRQ_DOMAIN if PCI_MSI |
|
|
|
config X86_IO_APIC |
|
def_bool y |
|
depends on X86_LOCAL_APIC || X86_UP_IOAPIC |
|
|
|
config X86_REROUTE_FOR_BROKEN_BOOT_IRQS |
|
bool "Reroute for broken boot IRQs" |
|
depends on X86_IO_APIC |
|
help |
|
This option enables a workaround that fixes a source of |
|
spurious interrupts. This is recommended when threaded |
|
interrupt handling is used on systems where the generation of |
|
superfluous "boot interrupts" cannot be disabled. |
|
|
|
Some chipsets generate a legacy INTx "boot IRQ" when the IRQ |
|
entry in the chipset's IO-APIC is masked (as, e.g. the RT |
|
kernel does during interrupt handling). On chipsets where this |
|
boot IRQ generation cannot be disabled, this workaround keeps |
|
the original IRQ line masked so that only the equivalent "boot |
|
IRQ" is delivered to the CPUs. The workaround also tells the |
|
kernel to set up the IRQ handler on the boot IRQ line. In this |
|
way only one interrupt is delivered to the kernel. Otherwise |
|
the spurious second interrupt may cause the kernel to bring |
|
down (vital) interrupt lines. |
|
|
|
Only affects "broken" chipsets. Interrupt sharing may be |
|
increased on these systems. |
|
|
|
config X86_MCE |
|
bool "Machine Check / overheating reporting" |
|
select GENERIC_ALLOCATOR |
|
default y |
|
help |
|
Machine Check support allows the processor to notify the |
|
kernel if it detects a problem (e.g. overheating, data corruption). |
|
The action the kernel takes depends on the severity of the problem, |
|
ranging from warning messages to halting the machine. |
|
|
|
config X86_MCELOG_LEGACY |
|
bool "Support for deprecated /dev/mcelog character device" |
|
depends on X86_MCE |
|
help |
|
Enable support for /dev/mcelog which is needed by the old mcelog |
|
userspace logging daemon. Consider switching to the new generation |
|
rasdaemon solution. |
|
|
|
config X86_MCE_INTEL |
|
def_bool y |
|
prompt "Intel MCE features" |
|
depends on X86_MCE && X86_LOCAL_APIC |
|
help |
|
Additional support for intel specific MCE features such as |
|
the thermal monitor. |
|
|
|
config X86_MCE_AMD |
|
def_bool y |
|
prompt "AMD MCE features" |
|
depends on X86_MCE && X86_LOCAL_APIC && AMD_NB |
|
help |
|
Additional support for AMD specific MCE features such as |
|
the DRAM Error Threshold. |
|
|
|
config X86_ANCIENT_MCE |
|
bool "Support for old Pentium 5 / WinChip machine checks" |
|
depends on X86_32 && X86_MCE |
|
help |
|
Include support for machine check handling on old Pentium 5 or WinChip |
|
systems. These typically need to be enabled explicitly on the command |
|
line. |
|
|
|
config X86_MCE_THRESHOLD |
|
depends on X86_MCE_AMD || X86_MCE_INTEL |
|
def_bool y |
|
|
|
config X86_MCE_INJECT |
|
depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS |
|
tristate "Machine check injector support" |
|
help |
|
Provide support for injecting machine checks for testing purposes. |
|
If you don't know what a machine check is and you don't do kernel |
|
QA it is safe to say n. |
|
|
|
source "arch/x86/events/Kconfig" |
|
|
|
config X86_LEGACY_VM86 |
|
bool "Legacy VM86 support" |
|
depends on X86_32 |
|
help |
|
This option allows user programs to put the CPU into V8086 |
|
mode, which is an 80286-era approximation of 16-bit real mode. |
|
|
|
Some very old versions of X and/or vbetool require this option |
|
for user mode setting. Similarly, DOSEMU will use it if |
|
available to accelerate real mode DOS programs. However, any |
|
recent version of DOSEMU, X, or vbetool should be fully |
|
functional even without kernel VM86 support, as they will all |
|
fall back to software emulation. Nevertheless, if you are using |
|
a 16-bit DOS program where 16-bit performance matters, vm86 |
|
mode might be faster than emulation and you might want to |
|
enable this option. |
|
|
|
Note that any app that works on a 64-bit kernel is unlikely to |
|
need this option, as 64-bit kernels don't, and can't, support |
|
V8086 mode. This option is also unrelated to 16-bit protected |
|
mode and is not needed to run most 16-bit programs under Wine. |
|
|
|
Enabling this option increases the complexity of the kernel |
|
and slows down exception handling a tiny bit. |
|
|
|
If unsure, say N here. |
|
|
|
config VM86 |
|
bool |
|
default X86_LEGACY_VM86 |
|
|
|
config X86_16BIT |
|
bool "Enable support for 16-bit segments" if EXPERT |
|
default y |
|
depends on MODIFY_LDT_SYSCALL |
|
help |
|
This option is required by programs like Wine to run 16-bit |
|
protected mode legacy code on x86 processors. Disabling |
|
this option saves about 300 bytes on i386, or around 6K text |
|
plus 16K runtime memory on x86-64, |
|
|
|
config X86_ESPFIX32 |
|
def_bool y |
|
depends on X86_16BIT && X86_32 |
|
|
|
config X86_ESPFIX64 |
|
def_bool y |
|
depends on X86_16BIT && X86_64 |
|
|
|
config X86_VSYSCALL_EMULATION |
|
bool "Enable vsyscall emulation" if EXPERT |
|
default y |
|
depends on X86_64 |
|
help |
|
This enables emulation of the legacy vsyscall page. Disabling |
|
it is roughly equivalent to booting with vsyscall=none, except |
|
that it will also disable the helpful warning if a program |
|
tries to use a vsyscall. With this option set to N, offending |
|
programs will just segfault, citing addresses of the form |
|
0xffffffffff600?00. |
|
|
|
This option is required by many programs built before 2013, and |
|
care should be used even with newer programs if set to N. |
|
|
|
Disabling this option saves about 7K of kernel size and |
|
possibly 4K of additional runtime pagetable memory. |
|
|
|
config X86_IOPL_IOPERM |
|
bool "IOPERM and IOPL Emulation" |
|
default y |
|
help |
|
This enables the ioperm() and iopl() syscalls which are necessary |
|
for legacy applications. |
|
|
|
Legacy IOPL support is an overbroad mechanism which allows user |
|
space aside of accessing all 65536 I/O ports also to disable |
|
interrupts. To gain this access the caller needs CAP_SYS_RAWIO |
|
capabilities and permission from potentially active security |
|
modules. |
|
|
|
The emulation restricts the functionality of the syscall to |
|
only allowing the full range I/O port access, but prevents the |
|
ability to disable interrupts from user space which would be |
|
granted if the hardware IOPL mechanism would be used. |
|
|
|
config TOSHIBA |
|
tristate "Toshiba Laptop support" |
|
depends on X86_32 |
|
help |
|
This adds a driver to safely access the System Management Mode of |
|
the CPU on Toshiba portables with a genuine Toshiba BIOS. It does |
|
not work on models with a Phoenix BIOS. The System Management Mode |
|
is used to set the BIOS and power saving options on Toshiba portables. |
|
|
|
For information on utilities to make use of this driver see the |
|
Toshiba Linux utilities web site at: |
|
<http://www.buzzard.org.uk/toshiba/>. |
|
|
|
Say Y if you intend to run this kernel on a Toshiba portable. |
|
Say N otherwise. |
|
|
|
config I8K |
|
tristate "Dell i8k legacy laptop support" |
|
select HWMON |
|
select SENSORS_DELL_SMM |
|
help |
|
This option enables legacy /proc/i8k userspace interface in hwmon |
|
dell-smm-hwmon driver. Character file /proc/i8k reports bios version, |
|
temperature and allows controlling fan speeds of Dell laptops via |
|
System Management Mode. For old Dell laptops (like Dell Inspiron 8000) |
|
it reports also power and hotkey status. For fan speed control is |
|
needed userspace package i8kutils. |
|
|
|
Say Y if you intend to run this kernel on old Dell laptops or want to |
|
use userspace package i8kutils. |
|
Say N otherwise. |
|
|
|
config X86_REBOOTFIXUPS |
|
bool "Enable X86 board specific fixups for reboot" |
|
depends on X86_32 |
|
help |
|
This enables chipset and/or board specific fixups to be done |
|
in order to get reboot to work correctly. This is only needed on |
|
some combinations of hardware and BIOS. The symptom, for which |
|
this config is intended, is when reboot ends with a stalled/hung |
|
system. |
|
|
|
Currently, the only fixup is for the Geode machines using |
|
CS5530A and CS5536 chipsets and the RDC R-321x SoC. |
|
|
|
Say Y if you want to enable the fixup. Currently, it's safe to |
|
enable this option even if you don't need it. |
|
Say N otherwise. |
|
|
|
config MICROCODE |
|
bool "CPU microcode loading support" |
|
default y |
|
depends on CPU_SUP_AMD || CPU_SUP_INTEL |
|
help |
|
If you say Y here, you will be able to update the microcode on |
|
Intel and AMD processors. The Intel support is for the IA32 family, |
|
e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The |
|
AMD support is for families 0x10 and later. You will obviously need |
|
the actual microcode binary data itself which is not shipped with |
|
the Linux kernel. |
|
|
|
The preferred method to load microcode from a detached initrd is described |
|
in Documentation/x86/microcode.rst. For that you need to enable |
|
CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the |
|
initrd for microcode blobs. |
|
|
|
In addition, you can build the microcode into the kernel. For that you |
|
need to add the vendor-supplied microcode to the CONFIG_EXTRA_FIRMWARE |
|
config option. |
|
|
|
config MICROCODE_INTEL |
|
bool "Intel microcode loading support" |
|
depends on MICROCODE |
|
default MICROCODE |
|
help |
|
This options enables microcode patch loading support for Intel |
|
processors. |
|
|
|
For the current Intel microcode data package go to |
|
<https://downloadcenter.intel.com> and search for |
|
'Linux Processor Microcode Data File'. |
|
|
|
config MICROCODE_AMD |
|
bool "AMD microcode loading support" |
|
depends on MICROCODE |
|
help |
|
If you select this option, microcode patch loading support for AMD |
|
processors will be enabled. |
|
|
|
config MICROCODE_OLD_INTERFACE |
|
bool "Ancient loading interface (DEPRECATED)" |
|
default n |
|
depends on MICROCODE |
|
help |
|
DO NOT USE THIS! This is the ancient /dev/cpu/microcode interface |
|
which was used by userspace tools like iucode_tool and microcode.ctl. |
|
It is inadequate because it runs too late to be able to properly |
|
load microcode on a machine and it needs special tools. Instead, you |
|
should've switched to the early loading method with the initrd or |
|
builtin microcode by now: Documentation/x86/microcode.rst |
|
|
|
config X86_MSR |
|
tristate "/dev/cpu/*/msr - Model-specific register support" |
|
help |
|
This device gives privileged processes access to the x86 |
|
Model-Specific Registers (MSRs). It is a character device with |
|
major 202 and minors 0 to 31 for /dev/cpu/0/msr to /dev/cpu/31/msr. |
|
MSR accesses are directed to a specific CPU on multi-processor |
|
systems. |
|
|
|
config X86_CPUID |
|
tristate "/dev/cpu/*/cpuid - CPU information support" |
|
help |
|
This device gives processes access to the x86 CPUID instruction to |
|
be executed on a specific processor. It is a character device |
|
with major 203 and minors 0 to 31 for /dev/cpu/0/cpuid to |
|
/dev/cpu/31/cpuid. |
|
|
|
choice |
|
prompt "High Memory Support" |
|
default HIGHMEM4G |
|
depends on X86_32 |
|
|
|
config NOHIGHMEM |
|
bool "off" |
|
help |
|
Linux can use up to 64 Gigabytes of physical memory on x86 systems. |
|
However, the address space of 32-bit x86 processors is only 4 |
|
Gigabytes large. That means that, if you have a large amount of |
|
physical memory, not all of it can be "permanently mapped" by the |
|
kernel. The physical memory that's not permanently mapped is called |
|
"high memory". |
|
|
|
If you are compiling a kernel which will never run on a machine with |
|
more than 1 Gigabyte total physical RAM, answer "off" here (default |
|
choice and suitable for most users). This will result in a "3GB/1GB" |
|
split: 3GB are mapped so that each process sees a 3GB virtual memory |
|
space and the remaining part of the 4GB virtual memory space is used |
|
by the kernel to permanently map as much physical memory as |
|
possible. |
|
|
|
If the machine has between 1 and 4 Gigabytes physical RAM, then |
|
answer "4GB" here. |
|
|
|
If more than 4 Gigabytes is used then answer "64GB" here. This |
|
selection turns Intel PAE (Physical Address Extension) mode on. |
|
PAE implements 3-level paging on IA32 processors. PAE is fully |
|
supported by Linux, PAE mode is implemented on all recent Intel |
|
processors (Pentium Pro and better). NOTE: If you say "64GB" here, |
|
then the kernel will not boot on CPUs that don't support PAE! |
|
|
|
The actual amount of total physical memory will either be |
|
auto detected or can be forced by using a kernel command line option |
|
such as "mem=256M". (Try "man bootparam" or see the documentation of |
|
your boot loader (lilo or loadlin) about how to pass options to the |
|
kernel at boot time.) |
|
|
|
If unsure, say "off". |
|
|
|
config HIGHMEM4G |
|
bool "4GB" |
|
help |
|
Select this if you have a 32-bit processor and between 1 and 4 |
|
gigabytes of physical RAM. |
|
|
|
config HIGHMEM64G |
|
bool "64GB" |
|
depends on !M486SX && !M486 && !M586 && !M586TSC && !M586MMX && !MGEODE_LX && !MGEODEGX1 && !MCYRIXIII && !MELAN && !MWINCHIPC6 && !WINCHIP3D && !MK6 |
|
select X86_PAE |
|
help |
|
Select this if you have a 32-bit processor and more than 4 |
|
gigabytes of physical RAM. |
|
|
|
endchoice |
|
|
|
choice |
|
prompt "Memory split" if EXPERT |
|
default VMSPLIT_3G |
|
depends on X86_32 |
|
help |
|
Select the desired split between kernel and user memory. |
|
|
|
If the address range available to the kernel is less than the |
|
physical memory installed, the remaining memory will be available |
|
as "high memory". Accessing high memory is a little more costly |
|
than low memory, as it needs to be mapped into the kernel first. |
|
Note that increasing the kernel address space limits the range |
|
available to user programs, making the address space there |
|
tighter. Selecting anything other than the default 3G/1G split |
|
will also likely make your kernel incompatible with binary-only |
|
kernel modules. |
|
|
|
If you are not absolutely sure what you are doing, leave this |
|
option alone! |
|
|
|
config VMSPLIT_3G |
|
bool "3G/1G user/kernel split" |
|
config VMSPLIT_3G_OPT |
|
depends on !X86_PAE |
|
bool "3G/1G user/kernel split (for full 1G low memory)" |
|
config VMSPLIT_2G |
|
bool "2G/2G user/kernel split" |
|
config VMSPLIT_2G_OPT |
|
depends on !X86_PAE |
|
bool "2G/2G user/kernel split (for full 2G low memory)" |
|
config VMSPLIT_1G |
|
bool "1G/3G user/kernel split" |
|
endchoice |
|
|
|
config PAGE_OFFSET |
|
hex |
|
default 0xB0000000 if VMSPLIT_3G_OPT |
|
default 0x80000000 if VMSPLIT_2G |
|
default 0x78000000 if VMSPLIT_2G_OPT |
|
default 0x40000000 if VMSPLIT_1G |
|
default 0xC0000000 |
|
depends on X86_32 |
|
|
|
config HIGHMEM |
|
def_bool y |
|
depends on X86_32 && (HIGHMEM64G || HIGHMEM4G) |
|
|
|
config X86_PAE |
|
bool "PAE (Physical Address Extension) Support" |
|
depends on X86_32 && !HIGHMEM4G |
|
select PHYS_ADDR_T_64BIT |
|
select SWIOTLB |
|
help |
|
PAE is required for NX support, and furthermore enables |
|
larger swapspace support for non-overcommit purposes. It |
|
has the cost of more pagetable lookup overhead, and also |
|
consumes more pagetable space per process. |
|
|
|
config X86_5LEVEL |
|
bool "Enable 5-level page tables support" |
|
default y |
|
select DYNAMIC_MEMORY_LAYOUT |
|
select SPARSEMEM_VMEMMAP |
|
depends on X86_64 |
|
help |
|
5-level paging enables access to larger address space: |
|
upto 128 PiB of virtual address space and 4 PiB of |
|
physical address space. |
|
|
|
It will be supported by future Intel CPUs. |
|
|
|
A kernel with the option enabled can be booted on machines that |
|
support 4- or 5-level paging. |
|
|
|
See Documentation/x86/x86_64/5level-paging.rst for more |
|
information. |
|
|
|
Say N if unsure. |
|
|
|
config X86_DIRECT_GBPAGES |
|
def_bool y |
|
depends on X86_64 |
|
help |
|
Certain kernel features effectively disable kernel |
|
linear 1 GB mappings (even if the CPU otherwise |
|
supports them), so don't confuse the user by printing |
|
that we have them enabled. |
|
|
|
config X86_CPA_STATISTICS |
|
bool "Enable statistic for Change Page Attribute" |
|
depends on DEBUG_FS |
|
help |
|
Expose statistics about the Change Page Attribute mechanism, which |
|
helps to determine the effectiveness of preserving large and huge |
|
page mappings when mapping protections are changed. |
|
|
|
config AMD_MEM_ENCRYPT |
|
bool "AMD Secure Memory Encryption (SME) support" |
|
depends on X86_64 && CPU_SUP_AMD |
|
select DMA_COHERENT_POOL |
|
select DYNAMIC_PHYSICAL_MASK |
|
select ARCH_USE_MEMREMAP_PROT |
|
select ARCH_HAS_FORCE_DMA_UNENCRYPTED |
|
select INSTRUCTION_DECODER |
|
help |
|
Say yes to enable support for the encryption of system memory. |
|
This requires an AMD processor that supports Secure Memory |
|
Encryption (SME). |
|
|
|
config AMD_MEM_ENCRYPT_ACTIVE_BY_DEFAULT |
|
bool "Activate AMD Secure Memory Encryption (SME) by default" |
|
default y |
|
depends on AMD_MEM_ENCRYPT |
|
help |
|
Say yes to have system memory encrypted by default if running on |
|
an AMD processor that supports Secure Memory Encryption (SME). |
|
|
|
If set to Y, then the encryption of system memory can be |
|
deactivated with the mem_encrypt=off command line option. |
|
|
|
If set to N, then the encryption of system memory can be |
|
activated with the mem_encrypt=on command line option. |
|
|
|
# Common NUMA Features |
|
config NUMA |
|
bool "NUMA Memory Allocation and Scheduler Support" |
|
depends on SMP |
|
depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP) |
|
default y if X86_BIGSMP |
|
help |
|
Enable NUMA (Non-Uniform Memory Access) support. |
|
|
|
The kernel will try to allocate memory used by a CPU on the |
|
local memory controller of the CPU and add some more |
|
NUMA awareness to the kernel. |
|
|
|
For 64-bit this is recommended if the system is Intel Core i7 |
|
(or later), AMD Opteron, or EM64T NUMA. |
|
|
|
For 32-bit this is only needed if you boot a 32-bit |
|
kernel on a 64-bit NUMA platform. |
|
|
|
Otherwise, you should say N. |
|
|
|
config AMD_NUMA |
|
def_bool y |
|
prompt "Old style AMD Opteron NUMA detection" |
|
depends on X86_64 && NUMA && PCI |
|
help |
|
Enable AMD NUMA node topology detection. You should say Y here if |
|
you have a multi processor AMD system. This uses an old method to |
|
read the NUMA configuration directly from the builtin Northbridge |
|
of Opteron. It is recommended to use X86_64_ACPI_NUMA instead, |
|
which also takes priority if both are compiled in. |
|
|
|
config X86_64_ACPI_NUMA |
|
def_bool y |
|
prompt "ACPI NUMA detection" |
|
depends on X86_64 && NUMA && ACPI && PCI |
|
select ACPI_NUMA |
|
help |
|
Enable ACPI SRAT based node topology detection. |
|
|
|
config NUMA_EMU |
|
bool "NUMA emulation" |
|
depends on NUMA |
|
help |
|
Enable NUMA emulation. A flat machine will be split |
|
into virtual nodes when booted with "numa=fake=N", where N is the |
|
number of nodes. This is only useful for debugging. |
|
|
|
config NODES_SHIFT |
|
int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP |
|
range 1 10 |
|
default "10" if MAXSMP |
|
default "6" if X86_64 |
|
default "3" |
|
depends on NEED_MULTIPLE_NODES |
|
help |
|
Specify the maximum number of NUMA Nodes available on the target |
|
system. Increases memory reserved to accommodate various tables. |
|
|
|
config ARCH_FLATMEM_ENABLE |
|
def_bool y |
|
depends on X86_32 && !NUMA |
|
|
|
config ARCH_SPARSEMEM_ENABLE |
|
def_bool y |
|
depends on X86_64 || NUMA || X86_32 || X86_32_NON_STANDARD |
|
select SPARSEMEM_STATIC if X86_32 |
|
select SPARSEMEM_VMEMMAP_ENABLE if X86_64 |
|
|
|
config ARCH_SPARSEMEM_DEFAULT |
|
def_bool X86_64 || (NUMA && X86_32) |
|
|
|
config ARCH_SELECT_MEMORY_MODEL |
|
def_bool y |
|
depends on ARCH_SPARSEMEM_ENABLE |
|
|
|
config ARCH_MEMORY_PROBE |
|
bool "Enable sysfs memory/probe interface" |
|
depends on X86_64 && MEMORY_HOTPLUG |
|
help |
|
This option enables a sysfs memory/probe interface for testing. |
|
See Documentation/admin-guide/mm/memory-hotplug.rst for more information. |
|
If you are unsure how to answer this question, answer N. |
|
|
|
config ARCH_PROC_KCORE_TEXT |
|
def_bool y |
|
depends on X86_64 && PROC_KCORE |
|
|
|
config ILLEGAL_POINTER_VALUE |
|
hex |
|
default 0 if X86_32 |
|
default 0xdead000000000000 if X86_64 |
|
|
|
config X86_PMEM_LEGACY_DEVICE |
|
bool |
|
|
|
config X86_PMEM_LEGACY |
|
tristate "Support non-standard NVDIMMs and ADR protected memory" |
|
depends on PHYS_ADDR_T_64BIT |
|
depends on BLK_DEV |
|
select X86_PMEM_LEGACY_DEVICE |
|
select NUMA_KEEP_MEMINFO if NUMA |
|
select LIBNVDIMM |
|
help |
|
Treat memory marked using the non-standard e820 type of 12 as used |
|
by the Intel Sandy Bridge-EP reference BIOS as protected memory. |
|
The kernel will offer these regions to the 'pmem' driver so |
|
they can be used for persistent storage. |
|
|
|
Say Y if unsure. |
|
|
|
config HIGHPTE |
|
bool "Allocate 3rd-level pagetables from highmem" |
|
depends on HIGHMEM |
|
help |
|
The VM uses one page table entry for each page of physical memory. |
|
For systems with a lot of RAM, this can be wasteful of precious |
|
low memory. Setting this option will put user-space page table |
|
entries in high memory. |
|
|
|
config X86_CHECK_BIOS_CORRUPTION |
|
bool "Check for low memory corruption" |
|
help |
|
Periodically check for memory corruption in low memory, which |
|
is suspected to be caused by BIOS. Even when enabled in the |
|
configuration, it is disabled at runtime. Enable it by |
|
setting "memory_corruption_check=1" on the kernel command |
|
line. By default it scans the low 64k of memory every 60 |
|
seconds; see the memory_corruption_check_size and |
|
memory_corruption_check_period parameters in |
|
Documentation/admin-guide/kernel-parameters.rst to adjust this. |
|
|
|
When enabled with the default parameters, this option has |
|
almost no overhead, as it reserves a relatively small amount |
|
of memory and scans it infrequently. It both detects corruption |
|
and prevents it from affecting the running system. |
|
|
|
It is, however, intended as a diagnostic tool; if repeatable |
|
BIOS-originated corruption always affects the same memory, |
|
you can use memmap= to prevent the kernel from using that |
|
memory. |
|
|
|
config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK |
|
bool "Set the default setting of memory_corruption_check" |
|
depends on X86_CHECK_BIOS_CORRUPTION |
|
default y |
|
help |
|
Set whether the default state of memory_corruption_check is |
|
on or off. |
|
|
|
config X86_RESERVE_LOW |
|
int "Amount of low memory, in kilobytes, to reserve for the BIOS" |
|
default 64 |
|
range 4 640 |
|
help |
|
Specify the amount of low memory to reserve for the BIOS. |
|
|
|
The first page contains BIOS data structures that the kernel |
|
must not use, so that page must always be reserved. |
|
|
|
By default we reserve the first 64K of physical RAM, as a |
|
number of BIOSes are known to corrupt that memory range |
|
during events such as suspend/resume or monitor cable |
|
insertion, so it must not be used by the kernel. |
|
|
|
You can set this to 4 if you are absolutely sure that you |
|
trust the BIOS to get all its memory reservations and usages |
|
right. If you know your BIOS have problems beyond the |
|
default 64K area, you can set this to 640 to avoid using the |
|
entire low memory range. |
|
|
|
If you have doubts about the BIOS (e.g. suspend/resume does |
|
not work or there's kernel crashes after certain hardware |
|
hotplug events) then you might want to enable |
|
X86_CHECK_BIOS_CORRUPTION=y to allow the kernel to check |
|
typical corruption patterns. |
|
|
|
Leave this to the default value of 64 if you are unsure. |
|
|
|
config MATH_EMULATION |
|
bool |
|
depends on MODIFY_LDT_SYSCALL |
|
prompt "Math emulation" if X86_32 && (M486SX || MELAN) |
|
help |
|
Linux can emulate a math coprocessor (used for floating point |
|
operations) if you don't have one. 486DX and Pentium processors have |
|
a math coprocessor built in, 486SX and 386 do not, unless you added |
|
a 487DX or 387, respectively. (The messages during boot time can |
|
give you some hints here ["man dmesg"].) Everyone needs either a |
|
coprocessor or this emulation. |
|
|
|
If you don't have a math coprocessor, you need to say Y here; if you |
|
say Y here even though you have a coprocessor, the coprocessor will |
|
be used nevertheless. (This behavior can be changed with the kernel |
|
command line option "no387", which comes handy if your coprocessor |
|
is broken. Try "man bootparam" or see the documentation of your boot |
|
loader (lilo or loadlin) about how to pass options to the kernel at |
|
boot time.) This means that it is a good idea to say Y here if you |
|
intend to use this kernel on different machines. |
|
|
|
More information about the internals of the Linux math coprocessor |
|
emulation can be found in <file:arch/x86/math-emu/README>. |
|
|
|
If you are not sure, say Y; apart from resulting in a 66 KB bigger |
|
kernel, it won't hurt. |
|
|
|
config MTRR |
|
def_bool y |
|
prompt "MTRR (Memory Type Range Register) support" if EXPERT |
|
help |
|
On Intel P6 family processors (Pentium Pro, Pentium II and later) |
|
the Memory Type Range Registers (MTRRs) may be used to control |
|
processor access to memory ranges. This is most useful if you have |
|
a video (VGA) card on a PCI or AGP bus. Enabling write-combining |
|
allows bus write transfers to be combined into a larger transfer |
|
before bursting over the PCI/AGP bus. This can increase performance |
|
of image write operations 2.5 times or more. Saying Y here creates a |
|
/proc/mtrr file which may be used to manipulate your processor's |
|
MTRRs. Typically the X server should use this. |
|
|
|
This code has a reasonably generic interface so that similar |
|
control registers on other processors can be easily supported |
|
as well: |
|
|
|
The Cyrix 6x86, 6x86MX and M II processors have Address Range |
|
Registers (ARRs) which provide a similar functionality to MTRRs. For |
|
these, the ARRs are used to emulate the MTRRs. |
|
The AMD K6-2 (stepping 8 and above) and K6-3 processors have two |
|
MTRRs. The Centaur C6 (WinChip) has 8 MCRs, allowing |
|
write-combining. All of these processors are supported by this code |
|
and it makes sense to say Y here if you have one of them. |
|
|
|
Saying Y here also fixes a problem with buggy SMP BIOSes which only |
|
set the MTRRs for the boot CPU and not for the secondary CPUs. This |
|
can lead to all sorts of problems, so it's good to say Y here. |
|
|
|
You can safely say Y even if your machine doesn't have MTRRs, you'll |
|
just add about 9 KB to your kernel. |
|
|
|
See <file:Documentation/x86/mtrr.rst> for more information. |
|
|
|
config MTRR_SANITIZER |
|
def_bool y |
|
prompt "MTRR cleanup support" |
|
depends on MTRR |
|
help |
|
Convert MTRR layout from continuous to discrete, so X drivers can |
|
add writeback entries. |
|
|
|
Can be disabled with disable_mtrr_cleanup on the kernel command line. |
|
The largest mtrr entry size for a continuous block can be set with |
|
mtrr_chunk_size. |
|
|
|
If unsure, say Y. |
|
|
|
config MTRR_SANITIZER_ENABLE_DEFAULT |
|
int "MTRR cleanup enable value (0-1)" |
|
range 0 1 |
|
default "0" |
|
depends on MTRR_SANITIZER |
|
help |
|
Enable mtrr cleanup default value |
|
|
|
config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT |
|
int "MTRR cleanup spare reg num (0-7)" |
|
range 0 7 |
|
default "1" |
|
depends on MTRR_SANITIZER |
|
help |
|
mtrr cleanup spare entries default, it can be changed via |
|
mtrr_spare_reg_nr=N on the kernel command line. |
|
|
|
config X86_PAT |
|
def_bool y |
|
prompt "x86 PAT support" if EXPERT |
|
depends on MTRR |
|
help |
|
Use PAT attributes to setup page level cache control. |
|
|
|
PATs are the modern equivalents of MTRRs and are much more |
|
flexible than MTRRs. |
|
|
|
Say N here if you see bootup problems (boot crash, boot hang, |
|
spontaneous reboots) or a non-working video driver. |
|
|
|
If unsure, say Y. |
|
|
|
config ARCH_USES_PG_UNCACHED |
|
def_bool y |
|
depends on X86_PAT |
|
|
|
config ARCH_RANDOM |
|
def_bool y |
|
prompt "x86 architectural random number generator" if EXPERT |
|
help |
|
Enable the x86 architectural RDRAND instruction |
|
(Intel Bull Mountain technology) to generate random numbers. |
|
If supported, this is a high bandwidth, cryptographically |
|
secure hardware random number generator. |
|
|
|
config X86_SMAP |
|
def_bool y |
|
prompt "Supervisor Mode Access Prevention" if EXPERT |
|
help |
|
Supervisor Mode Access Prevention (SMAP) is a security |
|
feature in newer Intel processors. There is a small |
|
performance cost if this enabled and turned on; there is |
|
also a small increase in the kernel size if this is enabled. |
|
|
|
If unsure, say Y. |
|
|
|
config X86_UMIP |
|
def_bool y |
|
prompt "User Mode Instruction Prevention" if EXPERT |
|
help |
|
User Mode Instruction Prevention (UMIP) is a security feature in |
|
some x86 processors. If enabled, a general protection fault is |
|
issued if the SGDT, SLDT, SIDT, SMSW or STR instructions are |
|
executed in user mode. These instructions unnecessarily expose |
|
information about the hardware state. |
|
|
|
The vast majority of applications do not use these instructions. |
|
For the very few that do, software emulation is provided in |
|
specific cases in protected and virtual-8086 modes. Emulated |
|
results are dummy. |
|
|
|
config X86_INTEL_MEMORY_PROTECTION_KEYS |
|
prompt "Memory Protection Keys" |
|
def_bool y |
|
# Note: only available in 64-bit mode |
|
depends on X86_64 && (CPU_SUP_INTEL || CPU_SUP_AMD) |
|
select ARCH_USES_HIGH_VMA_FLAGS |
|
select ARCH_HAS_PKEYS |
|
help |
|
Memory Protection Keys provides a mechanism for enforcing |
|
page-based protections, but without requiring modification of the |
|
page tables when an application changes protection domains. |
|
|
|
For details, see Documentation/core-api/protection-keys.rst |
|
|
|
If unsure, say y. |
|
|
|
choice |
|
prompt "TSX enable mode" |
|
depends on CPU_SUP_INTEL |
|
default X86_INTEL_TSX_MODE_OFF |
|
help |
|
Intel's TSX (Transactional Synchronization Extensions) feature |
|
allows to optimize locking protocols through lock elision which |
|
can lead to a noticeable performance boost. |
|
|
|
On the other hand it has been shown that TSX can be exploited |
|
to form side channel attacks (e.g. TAA) and chances are there |
|
will be more of those attacks discovered in the future. |
|
|
|
Therefore TSX is not enabled by default (aka tsx=off). An admin |
|
might override this decision by tsx=on the command line parameter. |
|
Even with TSX enabled, the kernel will attempt to enable the best |
|
possible TAA mitigation setting depending on the microcode available |
|
for the particular machine. |
|
|
|
This option allows to set the default tsx mode between tsx=on, =off |
|
and =auto. See Documentation/admin-guide/kernel-parameters.txt for more |
|
details. |
|
|
|
Say off if not sure, auto if TSX is in use but it should be used on safe |
|
platforms or on if TSX is in use and the security aspect of tsx is not |
|
relevant. |
|
|
|
config X86_INTEL_TSX_MODE_OFF |
|
bool "off" |
|
help |
|
TSX is disabled if possible - equals to tsx=off command line parameter. |
|
|
|
config X86_INTEL_TSX_MODE_ON |
|
bool "on" |
|
help |
|
TSX is always enabled on TSX capable HW - equals the tsx=on command |
|
line parameter. |
|
|
|
config X86_INTEL_TSX_MODE_AUTO |
|
bool "auto" |
|
help |
|
TSX is enabled on TSX capable HW that is believed to be safe against |
|
side channel attacks- equals the tsx=auto command line parameter. |
|
endchoice |
|
|
|
config X86_SGX |
|
bool "Software Guard eXtensions (SGX)" |
|
depends on X86_64 && CPU_SUP_INTEL |
|
depends on CRYPTO=y |
|
depends on CRYPTO_SHA256=y |
|
select SRCU |
|
select MMU_NOTIFIER |
|
help |
|
Intel(R) Software Guard eXtensions (SGX) is a set of CPU instructions |
|
that can be used by applications to set aside private regions of code |
|
and data, referred to as enclaves. An enclave's private memory can |
|
only be accessed by code running within the enclave. Accesses from |
|
outside the enclave, including other enclaves, are disallowed by |
|
hardware. |
|
|
|
If unsure, say N. |
|
|
|
config EFI |
|
bool "EFI runtime service support" |
|
depends on ACPI |
|
select UCS2_STRING |
|
select EFI_RUNTIME_WRAPPERS |
|
help |
|
This enables the kernel to use EFI runtime services that are |
|
available (such as the EFI variable services). |
|
|
|
This option is only useful on systems that have EFI firmware. |
|
In addition, you should use the latest ELILO loader available |
|
at <http://elilo.sourceforge.net> in order to take advantage |
|
of EFI runtime services. However, even with this option, the |
|
resultant kernel should continue to boot on existing non-EFI |
|
platforms. |
|
|
|
config EFI_STUB |
|
bool "EFI stub support" |
|
depends on EFI && !X86_USE_3DNOW |
|
depends on $(cc-option,-mabi=ms) || X86_32 |
|
select RELOCATABLE |
|
help |
|
This kernel feature allows a bzImage to be loaded directly |
|
by EFI firmware without the use of a bootloader. |
|
|
|
See Documentation/admin-guide/efi-stub.rst for more information. |
|
|
|
config EFI_MIXED |
|
bool "EFI mixed-mode support" |
|
depends on EFI_STUB && X86_64 |
|
help |
|
Enabling this feature allows a 64-bit kernel to be booted |
|
on a 32-bit firmware, provided that your CPU supports 64-bit |
|
mode. |
|
|
|
Note that it is not possible to boot a mixed-mode enabled |
|
kernel via the EFI boot stub - a bootloader that supports |
|
the EFI handover protocol must be used. |
|
|
|
If unsure, say N. |
|
|
|
source "kernel/Kconfig.hz" |
|
|
|
config KEXEC |
|
bool "kexec system call" |
|
select KEXEC_CORE |
|
help |
|
kexec is a system call that implements the ability to shutdown your |
|
current kernel, and to start another kernel. It is like a reboot |
|
but it is independent of the system firmware. And like a reboot |
|
you can start any kernel with it, not just Linux. |
|
|
|
The name comes from the similarity to the exec system call. |
|
|
|
It is an ongoing process to be certain the hardware in a machine |
|
is properly shutdown, so do not be surprised if this code does not |
|
initially work for you. As of this writing the exact hardware |
|
interface is strongly in flux, so no good recommendation can be |
|
made. |
|
|
|
config KEXEC_FILE |
|
bool "kexec file based system call" |
|
select KEXEC_CORE |
|
select BUILD_BIN2C |
|
depends on X86_64 |
|
depends on CRYPTO=y |
|
depends on CRYPTO_SHA256=y |
|
help |
|
This is new version of kexec system call. This system call is |
|
file based and takes file descriptors as system call argument |
|
for kernel and initramfs as opposed to list of segments as |
|
accepted by previous system call. |
|
|
|
config ARCH_HAS_KEXEC_PURGATORY |
|
def_bool KEXEC_FILE |
|
|
|
config KEXEC_SIG |
|
bool "Verify kernel signature during kexec_file_load() syscall" |
|
depends on KEXEC_FILE |
|
help |
|
|
|
This option makes the kexec_file_load() syscall check for a valid |
|
signature of the kernel image. The image can still be loaded without |
|
a valid signature unless you also enable KEXEC_SIG_FORCE, though if |
|
there's a signature that we can check, then it must be valid. |
|
|
|
In addition to this option, you need to enable signature |
|
verification for the corresponding kernel image type being |
|
loaded in order for this to work. |
|
|
|
config KEXEC_SIG_FORCE |
|
bool "Require a valid signature in kexec_file_load() syscall" |
|
depends on KEXEC_SIG |
|
help |
|
This option makes kernel signature verification mandatory for |
|
the kexec_file_load() syscall. |
|
|
|
config KEXEC_BZIMAGE_VERIFY_SIG |
|
bool "Enable bzImage signature verification support" |
|
depends on KEXEC_SIG |
|
depends on SIGNED_PE_FILE_VERIFICATION |
|
select SYSTEM_TRUSTED_KEYRING |
|
help |
|
Enable bzImage signature verification support. |
|
|
|
config CRASH_DUMP |
|
bool "kernel crash dumps" |
|
depends on X86_64 || (X86_32 && HIGHMEM) |
|
help |
|
Generate crash dump after being started by kexec. |
|
This should be normally only set in special crash dump kernels |
|
which are loaded in the main kernel with kexec-tools into |
|
a specially reserved region and then later executed after |
|
a crash by kdump/kexec. The crash dump kernel must be compiled |
|
to a memory address not used by the main kernel or BIOS using |
|
PHYSICAL_START, or it must be built as a relocatable image |
|
(CONFIG_RELOCATABLE=y). |
|
For more details see Documentation/admin-guide/kdump/kdump.rst |
|
|
|
config KEXEC_JUMP |
|
bool "kexec jump" |
|
depends on KEXEC && HIBERNATION |
|
help |
|
Jump between original kernel and kexeced kernel and invoke |
|
code in physical address mode via KEXEC |
|
|
|
config PHYSICAL_START |
|
hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP) |
|
default "0x1000000" |
|
help |
|
This gives the physical address where the kernel is loaded. |
|
|
|
If kernel is a not relocatable (CONFIG_RELOCATABLE=n) then |
|
bzImage will decompress itself to above physical address and |
|
run from there. Otherwise, bzImage will run from the address where |
|
it has been loaded by the boot loader and will ignore above physical |
|
address. |
|
|
|
In normal kdump cases one does not have to set/change this option |
|
as now bzImage can be compiled as a completely relocatable image |
|
(CONFIG_RELOCATABLE=y) and be used to load and run from a different |
|
address. This option is mainly useful for the folks who don't want |
|
to use a bzImage for capturing the crash dump and want to use a |
|
vmlinux instead. vmlinux is not relocatable hence a kernel needs |
|
to be specifically compiled to run from a specific memory area |
|
(normally a reserved region) and this option comes handy. |
|
|
|
So if you are using bzImage for capturing the crash dump, |
|
leave the value here unchanged to 0x1000000 and set |
|
CONFIG_RELOCATABLE=y. Otherwise if you plan to use vmlinux |
|
for capturing the crash dump change this value to start of |
|
the reserved region. In other words, it can be set based on |
|
the "X" value as specified in the "crashkernel=YM@XM" |
|
command line boot parameter passed to the panic-ed |
|
kernel. Please take a look at Documentation/admin-guide/kdump/kdump.rst |
|
for more details about crash dumps. |
|
|
|
Usage of bzImage for capturing the crash dump is recommended as |
|
one does not have to build two kernels. Same kernel can be used |
|
as production kernel and capture kernel. Above option should have |
|
gone away after relocatable bzImage support is introduced. But it |
|
is present because there are users out there who continue to use |
|
vmlinux for dump capture. This option should go away down the |
|
line. |
|
|
|
Don't change this unless you know what you are doing. |
|
|
|
config RELOCATABLE |
|
bool "Build a relocatable kernel" |
|
default y |
|
help |
|
This builds a kernel image that retains relocation information |
|
so it can be loaded someplace besides the default 1MB. |
|
The relocations tend to make the kernel binary about 10% larger, |
|
but are discarded at runtime. |
|
|
|
One use is for the kexec on panic case where the recovery kernel |
|
must live at a different physical address than the primary |
|
kernel. |
|
|
|
Note: If CONFIG_RELOCATABLE=y, then the kernel runs from the address |
|
it has been loaded at and the compile time physical address |
|
(CONFIG_PHYSICAL_START) is used as the minimum location. |
|
|
|
config RANDOMIZE_BASE |
|
bool "Randomize the address of the kernel image (KASLR)" |
|
depends on RELOCATABLE |
|
default y |
|
help |
|
In support of Kernel Address Space Layout Randomization (KASLR), |
|
this randomizes the physical address at which the kernel image |
|
is decompressed and the virtual address where the kernel |
|
image is mapped, as a security feature that deters exploit |
|
attempts relying on knowledge of the location of kernel |
|
code internals. |
|
|
|
On 64-bit, the kernel physical and virtual addresses are |
|
randomized separately. The physical address will be anywhere |
|
between 16MB and the top of physical memory (up to 64TB). The |
|
virtual address will be randomized from 16MB up to 1GB (9 bits |
|
of entropy). Note that this also reduces the memory space |
|
available to kernel modules from 1.5GB to 1GB. |
|
|
|
On 32-bit, the kernel physical and virtual addresses are |
|
randomized together. They will be randomized from 16MB up to |
|
512MB (8 bits of entropy). |
|
|
|
Entropy is generated using the RDRAND instruction if it is |
|
supported. If RDTSC is supported, its value is mixed into |
|
the entropy pool as well. If neither RDRAND nor RDTSC are |
|
supported, then entropy is read from the i8254 timer. The |
|
usable entropy is limited by the kernel being built using |
|
2GB addressing, and that PHYSICAL_ALIGN must be at a |
|
minimum of 2MB. As a result, only 10 bits of entropy are |
|
theoretically possible, but the implementations are further |
|
limited due to memory layouts. |
|
|
|
If unsure, say Y. |
|
|
|
# Relocation on x86 needs some additional build support |
|
config X86_NEED_RELOCS |
|
def_bool y |
|
depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE) |
|
|
|
config PHYSICAL_ALIGN |
|
hex "Alignment value to which kernel should be aligned" |
|
default "0x200000" |
|
range 0x2000 0x1000000 if X86_32 |
|
range 0x200000 0x1000000 if X86_64 |
|
help |
|
This value puts the alignment restrictions on physical address |
|
where kernel is loaded and run from. Kernel is compiled for an |
|
address which meets above alignment restriction. |
|
|
|
If bootloader loads the kernel at a non-aligned address and |
|
CONFIG_RELOCATABLE is set, kernel will move itself to nearest |
|
address aligned to above value and run from there. |
|
|
|
If bootloader loads the kernel at a non-aligned address and |
|
CONFIG_RELOCATABLE is not set, kernel will ignore the run time |
|
load address and decompress itself to the address it has been |
|
compiled for and run from there. The address for which kernel is |
|
compiled already meets above alignment restrictions. Hence the |
|
end result is that kernel runs from a physical address meeting |
|
above alignment restrictions. |
|
|
|
On 32-bit this value must be a multiple of 0x2000. On 64-bit |
|
this value must be a multiple of 0x200000. |
|
|
|
Don't change this unless you know what you are doing. |
|
|
|
config DYNAMIC_MEMORY_LAYOUT |
|
bool |
|
help |
|
This option makes base addresses of vmalloc and vmemmap as well as |
|
__PAGE_OFFSET movable during boot. |
|
|
|
config RANDOMIZE_MEMORY |
|
bool "Randomize the kernel memory sections" |
|
depends on X86_64 |
|
depends on RANDOMIZE_BASE |
|
select DYNAMIC_MEMORY_LAYOUT |
|
default RANDOMIZE_BASE |
|
help |
|
Randomizes the base virtual address of kernel memory sections |
|
(physical memory mapping, vmalloc & vmemmap). This security feature |
|
makes exploits relying on predictable memory locations less reliable. |
|
|
|
The order of allocations remains unchanged. Entropy is generated in |
|
the same way as RANDOMIZE_BASE. Current implementation in the optimal |
|
configuration have in average 30,000 different possible virtual |
|
addresses for each memory section. |
|
|
|
If unsure, say Y. |
|
|
|
config RANDOMIZE_MEMORY_PHYSICAL_PADDING |
|
hex "Physical memory mapping padding" if EXPERT |
|
depends on RANDOMIZE_MEMORY |
|
default "0xa" if MEMORY_HOTPLUG |
|
default "0x0" |
|
range 0x1 0x40 if MEMORY_HOTPLUG |
|
range 0x0 0x40 |
|
help |
|
Define the padding in terabytes added to the existing physical |
|
memory size during kernel memory randomization. It is useful |
|
for memory hotplug support but reduces the entropy available for |
|
address randomization. |
|
|
|
If unsure, leave at the default value. |
|
|
|
config HOTPLUG_CPU |
|
def_bool y |
|
depends on SMP |
|
|
|
config BOOTPARAM_HOTPLUG_CPU0 |
|
bool "Set default setting of cpu0_hotpluggable" |
|
depends on HOTPLUG_CPU |
|
help |
|
Set whether default state of cpu0_hotpluggable is on or off. |
|
|
|
Say Y here to enable CPU0 hotplug by default. If this switch |
|
is turned on, there is no need to give cpu0_hotplug kernel |
|
parameter and the CPU0 hotplug feature is enabled by default. |
|
|
|
Please note: there are two known CPU0 dependencies if you want |
|
to enable the CPU0 hotplug feature either by this switch or by |
|
cpu0_hotplug kernel parameter. |
|
|
|
First, resume from hibernate or suspend always starts from CPU0. |
|
So hibernate and suspend are prevented if CPU0 is offline. |
|
|
|
Second dependency is PIC interrupts always go to CPU0. CPU0 can not |
|
offline if any interrupt can not migrate out of CPU0. There may |
|
be other CPU0 dependencies. |
|
|
|
Please make sure the dependencies are under your control before |
|
you enable this feature. |
|
|
|
Say N if you don't want to enable CPU0 hotplug feature by default. |
|
You still can enable the CPU0 hotplug feature at boot by kernel |
|
parameter cpu0_hotplug. |
|
|
|
config DEBUG_HOTPLUG_CPU0 |
|
def_bool n |
|
prompt "Debug CPU0 hotplug" |
|
depends on HOTPLUG_CPU |
|
help |
|
Enabling this option offlines CPU0 (if CPU0 can be offlined) as |
|
soon as possible and boots up userspace with CPU0 offlined. User |
|
can online CPU0 back after boot time. |
|
|
|
To debug CPU0 hotplug, you need to enable CPU0 offline/online |
|
feature by either turning on CONFIG_BOOTPARAM_HOTPLUG_CPU0 during |
|
compilation or giving cpu0_hotplug kernel parameter at boot. |
|
|
|
If unsure, say N. |
|
|
|
config COMPAT_VDSO |
|
def_bool n |
|
prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)" |
|
depends on COMPAT_32 |
|
help |
|
Certain buggy versions of glibc will crash if they are |
|
presented with a 32-bit vDSO that is not mapped at the address |
|
indicated in its segment table. |
|
|
|
The bug was introduced by f866314b89d56845f55e6f365e18b31ec978ec3a |
|
and fixed by 3b3ddb4f7db98ec9e912ccdf54d35df4aa30e04a and |
|
49ad572a70b8aeb91e57483a11dd1b77e31c4468. Glibc 2.3.3 is |
|
the only released version with the bug, but OpenSUSE 9 |
|
contains a buggy "glibc 2.3.2". |
|
|
|
The symptom of the bug is that everything crashes on startup, saying: |
|
dl_main: Assertion `(void *) ph->p_vaddr == _rtld_local._dl_sysinfo_dso' failed! |
|
|
|
Saying Y here changes the default value of the vdso32 boot |
|
option from 1 to 0, which turns off the 32-bit vDSO entirely. |
|
This works around the glibc bug but hurts performance. |
|
|
|
If unsure, say N: if you are compiling your own kernel, you |
|
are unlikely to be using a buggy version of glibc. |
|
|
|
choice |
|
prompt "vsyscall table for legacy applications" |
|
depends on X86_64 |
|
default LEGACY_VSYSCALL_XONLY |
|
help |
|
Legacy user code that does not know how to find the vDSO expects |
|
to be able to issue three syscalls by calling fixed addresses in |
|
kernel space. Since this location is not randomized with ASLR, |
|
it can be used to assist security vulnerability exploitation. |
|
|
|
This setting can be changed at boot time via the kernel command |
|
line parameter vsyscall=[emulate|xonly|none]. |
|
|
|
On a system with recent enough glibc (2.14 or newer) and no |
|
static binaries, you can say None without a performance penalty |
|
to improve security. |
|
|
|
If unsure, select "Emulate execution only". |
|
|
|
config LEGACY_VSYSCALL_EMULATE |
|
bool "Full emulation" |
|
help |
|
The kernel traps and emulates calls into the fixed vsyscall |
|
address mapping. This makes the mapping non-executable, but |
|
it still contains readable known contents, which could be |
|
used in certain rare security vulnerability exploits. This |
|
configuration is recommended when using legacy userspace |
|
that still uses vsyscalls along with legacy binary |
|
instrumentation tools that require code to be readable. |
|
|
|
An example of this type of legacy userspace is running |
|
Pin on an old binary that still uses vsyscalls. |
|
|
|
config LEGACY_VSYSCALL_XONLY |
|
bool "Emulate execution only" |
|
help |
|
The kernel traps and emulates calls into the fixed vsyscall |
|
address mapping and does not allow reads. This |
|
configuration is recommended when userspace might use the |
|
legacy vsyscall area but support for legacy binary |
|
instrumentation of legacy code is not needed. It mitigates |
|
certain uses of the vsyscall area as an ASLR-bypassing |
|
buffer. |
|
|
|
config LEGACY_VSYSCALL_NONE |
|
bool "None" |
|
help |
|
There will be no vsyscall mapping at all. This will |
|
eliminate any risk of ASLR bypass due to the vsyscall |
|
fixed address mapping. Attempts to use the vsyscalls |
|
will be reported to dmesg, so that either old or |
|
malicious userspace programs can be identified. |
|
|
|
endchoice |
|
|
|
config CMDLINE_BOOL |
|
bool "Built-in kernel command line" |
|
help |
|
Allow for specifying boot arguments to the kernel at |
|
build time. On some systems (e.g. embedded ones), it is |
|
necessary or convenient to provide some or all of the |
|
kernel boot arguments with the kernel itself (that is, |
|
to not rely on the boot loader to provide them.) |
|
|
|
To compile command line arguments into the kernel, |
|
set this option to 'Y', then fill in the |
|
boot arguments in CONFIG_CMDLINE. |
|
|
|
Systems with fully functional boot loaders (i.e. non-embedded) |
|
should leave this option set to 'N'. |
|
|
|
config CMDLINE |
|
string "Built-in kernel command string" |
|
depends on CMDLINE_BOOL |
|
default "" |
|
help |
|
Enter arguments here that should be compiled into the kernel |
|
image and used at boot time. If the boot loader provides a |
|
command line at boot time, it is appended to this string to |
|
form the full kernel command line, when the system boots. |
|
|
|
However, you can use the CONFIG_CMDLINE_OVERRIDE option to |
|
change this behavior. |
|
|
|
In most cases, the command line (whether built-in or provided |
|
by the boot loader) should specify the device for the root |
|
file system. |
|
|
|
config CMDLINE_OVERRIDE |
|
bool "Built-in command line overrides boot loader arguments" |
|
depends on CMDLINE_BOOL && CMDLINE != "" |
|
help |
|
Set this option to 'Y' to have the kernel ignore the boot loader |
|
command line, and use ONLY the built-in command line. |
|
|
|
This is used to work around broken boot loaders. This should |
|
be set to 'N' under normal conditions. |
|
|
|
config MODIFY_LDT_SYSCALL |
|
bool "Enable the LDT (local descriptor table)" if EXPERT |
|
default y |
|
help |
|
Linux can allow user programs to install a per-process x86 |
|
Local Descriptor Table (LDT) using the modify_ldt(2) system |
|
call. This is required to run 16-bit or segmented code such as |
|
DOSEMU or some Wine programs. It is also used by some very old |
|
threading libraries. |
|
|
|
Enabling this feature adds a small amount of overhead to |
|
context switches and increases the low-level kernel attack |
|
surface. Disabling it removes the modify_ldt(2) system call. |
|
|
|
Saying 'N' here may make sense for embedded or server kernels. |
|
|
|
source "kernel/livepatch/Kconfig" |
|
|
|
endmenu |
|
|
|
config ARCH_HAS_ADD_PAGES |
|
def_bool y |
|
depends on X86_64 && ARCH_ENABLE_MEMORY_HOTPLUG |
|
|
|
config ARCH_ENABLE_MEMORY_HOTPLUG |
|
def_bool y |
|
depends on X86_64 || (X86_32 && HIGHMEM) |
|
|
|
config ARCH_ENABLE_MEMORY_HOTREMOVE |
|
def_bool y |
|
depends on MEMORY_HOTPLUG |
|
|
|
config USE_PERCPU_NUMA_NODE_ID |
|
def_bool y |
|
depends on NUMA |
|
|
|
config ARCH_ENABLE_SPLIT_PMD_PTLOCK |
|
def_bool y |
|
depends on X86_64 || X86_PAE |
|
|
|
config ARCH_ENABLE_HUGEPAGE_MIGRATION |
|
def_bool y |
|
depends on X86_64 && HUGETLB_PAGE && MIGRATION |
|
|
|
config ARCH_ENABLE_THP_MIGRATION |
|
def_bool y |
|
depends on X86_64 && TRANSPARENT_HUGEPAGE |
|
|
|
menu "Power management and ACPI options" |
|
|
|
config ARCH_HIBERNATION_HEADER |
|
def_bool y |
|
depends on HIBERNATION |
|
|
|
source "kernel/power/Kconfig" |
|
|
|
source "drivers/acpi/Kconfig" |
|
|
|
config X86_APM_BOOT |
|
def_bool y |
|
depends on APM |
|
|
|
menuconfig APM |
|
tristate "APM (Advanced Power Management) BIOS support" |
|
depends on X86_32 && PM_SLEEP |
|
help |
|
APM is a BIOS specification for saving power using several different |
|
techniques. This is mostly useful for battery powered laptops with |
|
APM compliant BIOSes. If you say Y here, the system time will be |
|
reset after a RESUME operation, the /proc/apm device will provide |
|
battery status information, and user-space programs will receive |
|
notification of APM "events" (e.g. battery status change). |
|
|
|
If you select "Y" here, you can disable actual use of the APM |
|
BIOS by passing the "apm=off" option to the kernel at boot time. |
|
|
|
Note that the APM support is almost completely disabled for |
|
machines with more than one CPU. |
|
|
|
In order to use APM, you will need supporting software. For location |
|
and more information, read <file:Documentation/power/apm-acpi.rst> |
|
and the Battery Powered Linux mini-HOWTO, available from |
|
<http://www.tldp.org/docs.html#howto>. |
|
|
|
This driver does not spin down disk drives (see the hdparm(8) |
|
manpage ("man 8 hdparm") for that), and it doesn't turn off |
|
VESA-compliant "green" monitors. |
|
|
|
This driver does not support the TI 4000M TravelMate and the ACER |
|
486/DX4/75 because they don't have compliant BIOSes. Many "green" |
|
desktop machines also don't have compliant BIOSes, and this driver |
|
may cause those machines to panic during the boot phase. |
|
|
|
Generally, if you don't have a battery in your machine, there isn't |
|
much point in using this driver and you should say N. If you get |
|
random kernel OOPSes or reboots that don't seem to be related to |
|
anything, try disabling/enabling this option (or disabling/enabling |
|
APM in your BIOS). |
|
|
|
Some other things you should try when experiencing seemingly random, |
|
"weird" problems: |
|
|
|
1) make sure that you have enough swap space and that it is |
|
enabled. |
|
2) pass the "no-hlt" option to the kernel |
|
3) switch on floating point emulation in the kernel and pass |
|
the "no387" option to the kernel |
|
4) pass the "floppy=nodma" option to the kernel |
|
5) pass the "mem=4M" option to the kernel (thereby disabling |
|
all but the first 4 MB of RAM) |
|
6) make sure that the CPU is not over clocked. |
|
7) read the sig11 FAQ at <http://www.bitwizard.nl/sig11/> |
|
8) disable the cache from your BIOS settings |
|
9) install a fan for the video card or exchange video RAM |
|
10) install a better fan for the CPU |
|
11) exchange RAM chips |
|
12) exchange the motherboard. |
|
|
|
To compile this driver as a module, choose M here: the |
|
module will be called apm. |
|
|
|
if APM |
|
|
|
config APM_IGNORE_USER_SUSPEND |
|
bool "Ignore USER SUSPEND" |
|
help |
|
This option will ignore USER SUSPEND requests. On machines with a |
|
compliant APM BIOS, you want to say N. However, on the NEC Versa M |
|
series notebooks, it is necessary to say Y because of a BIOS bug. |
|
|
|
config APM_DO_ENABLE |
|
bool "Enable PM at boot time" |
|
help |
|
Enable APM features at boot time. From page 36 of the APM BIOS |
|
specification: "When disabled, the APM BIOS does not automatically |
|
power manage devices, enter the Standby State, enter the Suspend |
|
State, or take power saving steps in response to CPU Idle calls." |
|
This driver will make CPU Idle calls when Linux is idle (unless this |
|
feature is turned off -- see "Do CPU IDLE calls", below). This |
|
should always save battery power, but more complicated APM features |
|
will be dependent on your BIOS implementation. You may need to turn |
|
this option off if your computer hangs at boot time when using APM |
|
support, or if it beeps continuously instead of suspending. Turn |
|
this off if you have a NEC UltraLite Versa 33/C or a Toshiba |
|
T400CDT. This is off by default since most machines do fine without |
|
this feature. |
|
|
|
config APM_CPU_IDLE |
|
depends on CPU_IDLE |
|
bool "Make CPU Idle calls when idle" |
|
help |
|
Enable calls to APM CPU Idle/CPU Busy inside the kernel's idle loop. |
|
On some machines, this can activate improved power savings, such as |
|
a slowed CPU clock rate, when the machine is idle. These idle calls |
|
are made after the idle loop has run for some length of time (e.g., |
|
333 mS). On some machines, this will cause a hang at boot time or |
|
whenever the CPU becomes idle. (On machines with more than one CPU, |
|
this option does nothing.) |
|
|
|
config APM_DISPLAY_BLANK |
|
bool "Enable console blanking using APM" |
|
help |
|
Enable console blanking using the APM. Some laptops can use this to |
|
turn off the LCD backlight when the screen blanker of the Linux |
|
virtual console blanks the screen. Note that this is only used by |
|
the virtual console screen blanker, and won't turn off the backlight |
|
when using the X Window system. This also doesn't have anything to |
|
do with your VESA-compliant power-saving monitor. Further, this |
|
option doesn't work for all laptops -- it might not turn off your |
|
backlight at all, or it might print a lot of errors to the console, |
|
especially if you are using gpm. |
|
|
|
config APM_ALLOW_INTS |
|
bool "Allow interrupts during APM BIOS calls" |
|
help |
|
Normally we disable external interrupts while we are making calls to |
|
the APM BIOS as a measure to lessen the effects of a badly behaving |
|
BIOS implementation. The BIOS should reenable interrupts if it |
|
needs to. Unfortunately, some BIOSes do not -- especially those in |
|
many of the newer IBM Thinkpads. If you experience hangs when you |
|
suspend, try setting this to Y. Otherwise, say N. |
|
|
|
endif # APM |
|
|
|
source "drivers/cpufreq/Kconfig" |
|
|
|
source "drivers/cpuidle/Kconfig" |
|
|
|
source "drivers/idle/Kconfig" |
|
|
|
endmenu |
|
|
|
|
|
menu "Bus options (PCI etc.)" |
|
|
|
choice |
|
prompt "PCI access mode" |
|
depends on X86_32 && PCI |
|
default PCI_GOANY |
|
help |
|
On PCI systems, the BIOS can be used to detect the PCI devices and |
|
determine their configuration. However, some old PCI motherboards |
|
have BIOS bugs and may crash if this is done. Also, some embedded |
|
PCI-based systems don't have any BIOS at all. Linux can also try to |
|
detect the PCI hardware directly without using the BIOS. |
|
|
|
With this option, you can specify how Linux should detect the |
|
PCI devices. If you choose "BIOS", the BIOS will be used, |
|
if you choose "Direct", the BIOS won't be used, and if you |
|
choose "MMConfig", then PCI Express MMCONFIG will be used. |
|
If you choose "Any", the kernel will try MMCONFIG, then the |
|
direct access method and falls back to the BIOS if that doesn't |
|
work. If unsure, go with the default, which is "Any". |
|
|
|
config PCI_GOBIOS |
|
bool "BIOS" |
|
|
|
config PCI_GOMMCONFIG |
|
bool "MMConfig" |
|
|
|
config PCI_GODIRECT |
|
bool "Direct" |
|
|
|
config PCI_GOOLPC |
|
bool "OLPC XO-1" |
|
depends on OLPC |
|
|
|
config PCI_GOANY |
|
bool "Any" |
|
|
|
endchoice |
|
|
|
config PCI_BIOS |
|
def_bool y |
|
depends on X86_32 && PCI && (PCI_GOBIOS || PCI_GOANY) |
|
|
|
# x86-64 doesn't support PCI BIOS access from long mode so always go direct. |
|
config PCI_DIRECT |
|
def_bool y |
|
depends on PCI && (X86_64 || (PCI_GODIRECT || PCI_GOANY || PCI_GOOLPC || PCI_GOMMCONFIG)) |
|
|
|
config PCI_MMCONFIG |
|
bool "Support mmconfig PCI config space access" if X86_64 |
|
default y |
|
depends on PCI && (ACPI || JAILHOUSE_GUEST) |
|
depends on X86_64 || (PCI_GOANY || PCI_GOMMCONFIG) |
|
|
|
config PCI_OLPC |
|
def_bool y |
|
depends on PCI && OLPC && (PCI_GOOLPC || PCI_GOANY) |
|
|
|
config PCI_XEN |
|
def_bool y |
|
depends on PCI && XEN |
|
select SWIOTLB_XEN |
|
|
|
config MMCONF_FAM10H |
|
def_bool y |
|
depends on X86_64 && PCI_MMCONFIG && ACPI |
|
|
|
config PCI_CNB20LE_QUIRK |
|
bool "Read CNB20LE Host Bridge Windows" if EXPERT |
|
depends on PCI |
|
help |
|
Read the PCI windows out of the CNB20LE host bridge. This allows |
|
PCI hotplug to work on systems with the CNB20LE chipset which do |
|
not have ACPI. |
|
|
|
There's no public spec for this chipset, and this functionality |
|
is known to be incomplete. |
|
|
|
You should say N unless you know you need this. |
|
|
|
config ISA_BUS |
|
bool "ISA bus support on modern systems" if EXPERT |
|
help |
|
Expose ISA bus device drivers and options available for selection and |
|
configuration. Enable this option if your target machine has an ISA |
|
bus. ISA is an older system, displaced by PCI and newer bus |
|
architectures -- if your target machine is modern, it probably does |
|
not have an ISA bus. |
|
|
|
If unsure, say N. |
|
|
|
# x86_64 have no ISA slots, but can have ISA-style DMA. |
|
config ISA_DMA_API |
|
bool "ISA-style DMA support" if (X86_64 && EXPERT) |
|
default y |
|
help |
|
Enables ISA-style DMA support for devices requiring such controllers. |
|
If unsure, say Y. |
|
|
|
if X86_32 |
|
|
|
config ISA |
|
bool "ISA support" |
|
help |
|
Find out whether you have ISA slots on your motherboard. ISA is the |
|
name of a bus system, i.e. the way the CPU talks to the other stuff |
|
inside your box. Other bus systems are PCI, EISA, MicroChannel |
|
(MCA) or VESA. ISA is an older system, now being displaced by PCI; |
|
newer boards don't support it. If you have ISA, say Y, otherwise N. |
|
|
|
config SCx200 |
|
tristate "NatSemi SCx200 support" |
|
help |
|
This provides basic support for National Semiconductor's |
|
(now AMD's) Geode processors. The driver probes for the |
|
PCI-IDs of several on-chip devices, so its a good dependency |
|
for other scx200_* drivers. |
|
|
|
If compiled as a module, the driver is named scx200. |
|
|
|
config SCx200HR_TIMER |
|
tristate "NatSemi SCx200 27MHz High-Resolution Timer Support" |
|
depends on SCx200 |
|
default y |
|
help |
|
This driver provides a clocksource built upon the on-chip |
|
27MHz high-resolution timer. Its also a workaround for |
|
NSC Geode SC-1100's buggy TSC, which loses time when the |
|
processor goes idle (as is done by the scheduler). The |
|
other workaround is idle=poll boot option. |
|
|
|
config OLPC |
|
bool "One Laptop Per Child support" |
|
depends on !X86_PAE |
|
select GPIOLIB |
|
select OF |
|
select OF_PROMTREE |
|
select IRQ_DOMAIN |
|
select OLPC_EC |
|
help |
|
Add support for detecting the unique features of the OLPC |
|
XO hardware. |
|
|
|
config OLPC_XO1_PM |
|
bool "OLPC XO-1 Power Management" |
|
depends on OLPC && MFD_CS5535=y && PM_SLEEP |
|
help |
|
Add support for poweroff and suspend of the OLPC XO-1 laptop. |
|
|
|
config OLPC_XO1_RTC |
|
bool "OLPC XO-1 Real Time Clock" |
|
depends on OLPC_XO1_PM && RTC_DRV_CMOS |
|
help |
|
Add support for the XO-1 real time clock, which can be used as a |
|
programmable wakeup source. |
|
|
|
config OLPC_XO1_SCI |
|
bool "OLPC XO-1 SCI extras" |
|
depends on OLPC && OLPC_XO1_PM && GPIO_CS5535=y |
|
depends on INPUT=y |
|
select POWER_SUPPLY |
|
help |
|
Add support for SCI-based features of the OLPC XO-1 laptop: |
|
- EC-driven system wakeups |
|
- Power button |
|
- Ebook switch |
|
- Lid switch |
|
- AC adapter status updates |
|
- Battery status updates |
|
|
|
config OLPC_XO15_SCI |
|
bool "OLPC XO-1.5 SCI extras" |
|
depends on OLPC && ACPI |
|
select POWER_SUPPLY |
|
help |
|
Add support for SCI-based features of the OLPC XO-1.5 laptop: |
|
- EC-driven system wakeups |
|
- AC adapter status updates |
|
- Battery status updates |
|
|
|
config ALIX |
|
bool "PCEngines ALIX System Support (LED setup)" |
|
select GPIOLIB |
|
help |
|
This option enables system support for the PCEngines ALIX. |
|
At present this just sets up LEDs for GPIO control on |
|
ALIX2/3/6 boards. However, other system specific setup should |
|
get added here. |
|
|
|
Note: You must still enable the drivers for GPIO and LED support |
|
(GPIO_CS5535 & LEDS_GPIO) to actually use the LEDs |
|
|
|
Note: You have to set alix.force=1 for boards with Award BIOS. |
|
|
|
config NET5501 |
|
bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)" |
|
select GPIOLIB |
|
help |
|
This option enables system support for the Soekris Engineering net5501. |
|
|
|
config GEOS |
|
bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)" |
|
select GPIOLIB |
|
depends on DMI |
|
help |
|
This option enables system support for the Traverse Technologies GEOS. |
|
|
|
config TS5500 |
|
bool "Technologic Systems TS-5500 platform support" |
|
depends on MELAN |
|
select CHECK_SIGNATURE |
|
select NEW_LEDS |
|
select LEDS_CLASS |
|
help |
|
This option enables system support for the Technologic Systems TS-5500. |
|
|
|
endif # X86_32 |
|
|
|
config AMD_NB |
|
def_bool y |
|
depends on CPU_SUP_AMD && PCI |
|
|
|
config X86_SYSFB |
|
bool "Mark VGA/VBE/EFI FB as generic system framebuffer" |
|
help |
|
Firmwares often provide initial graphics framebuffers so the BIOS, |
|
bootloader or kernel can show basic video-output during boot for |
|
user-guidance and debugging. Historically, x86 used the VESA BIOS |
|
Extensions and EFI-framebuffers for this, which are mostly limited |
|
to x86. |
|
This option, if enabled, marks VGA/VBE/EFI framebuffers as generic |
|
framebuffers so the new generic system-framebuffer drivers can be |
|
used on x86. If the framebuffer is not compatible with the generic |
|
modes, it is advertised as fallback platform framebuffer so legacy |
|
drivers like efifb, vesafb and uvesafb can pick it up. |
|
If this option is not selected, all system framebuffers are always |
|
marked as fallback platform framebuffers as usual. |
|
|
|
Note: Legacy fbdev drivers, including vesafb, efifb, uvesafb, will |
|
not be able to pick up generic system framebuffers if this option |
|
is selected. You are highly encouraged to enable simplefb as |
|
replacement if you select this option. simplefb can correctly deal |
|
with generic system framebuffers. But you should still keep vesafb |
|
and others enabled as fallback if a system framebuffer is |
|
incompatible with simplefb. |
|
|
|
If unsure, say Y. |
|
|
|
endmenu |
|
|
|
|
|
menu "Binary Emulations" |
|
|
|
config IA32_EMULATION |
|
bool "IA32 Emulation" |
|
depends on X86_64 |
|
select ARCH_WANT_OLD_COMPAT_IPC |
|
select BINFMT_ELF |
|
select COMPAT_OLD_SIGACTION |
|
help |
|
Include code to run legacy 32-bit programs under a |
|
64-bit kernel. You should likely turn this on, unless you're |
|
100% sure that you don't have any 32-bit programs left. |
|
|
|
config IA32_AOUT |
|
tristate "IA32 a.out support" |
|
depends on IA32_EMULATION |
|
depends on BROKEN |
|
help |
|
Support old a.out binaries in the 32bit emulation. |
|
|
|
config X86_X32 |
|
bool "x32 ABI for 64-bit mode" |
|
depends on X86_64 |
|
help |
|
Include code to run binaries for the x32 native 32-bit ABI |
|
for 64-bit processors. An x32 process gets access to the |
|
full 64-bit register file and wide data path while leaving |
|
pointers at 32 bits for smaller memory footprint. |
|
|
|
You will need a recent binutils (2.22 or later) with |
|
elf32_x86_64 support enabled to compile a kernel with this |
|
option set. |
|
|
|
config COMPAT_32 |
|
def_bool y |
|
depends on IA32_EMULATION || X86_32 |
|
select HAVE_UID16 |
|
select OLD_SIGSUSPEND3 |
|
|
|
config COMPAT |
|
def_bool y |
|
depends on IA32_EMULATION || X86_X32 |
|
|
|
if COMPAT |
|
config COMPAT_FOR_U64_ALIGNMENT |
|
def_bool y |
|
|
|
config SYSVIPC_COMPAT |
|
def_bool y |
|
depends on SYSVIPC |
|
endif |
|
|
|
endmenu |
|
|
|
|
|
config HAVE_ATOMIC_IOMAP |
|
def_bool y |
|
depends on X86_32 |
|
|
|
source "drivers/firmware/Kconfig" |
|
|
|
source "arch/x86/kvm/Kconfig" |
|
|
|
source "arch/x86/Kconfig.assembler"
|
|
|