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-rw-r--r--arch/x86/Kconfig2305
1 files changed, 1293 insertions, 1012 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 4b4a7f32b68e..80527299f859 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -3,7 +3,7 @@
config 64BIT
bool "64-bit kernel" if "$(ARCH)" = "x86"
default "$(ARCH)" != "i386"
- ---help---
+ help
Say yes to build a 64-bit kernel - formerly known as x86_64
Say no to build a 32-bit kernel - formerly known as i386
@@ -14,25 +14,41 @@ config X86_32
select ARCH_WANT_IPC_PARSE_VERSION
select CLKSRC_I8253
select CLONE_BACKWARDS
- select HAVE_AOUT
- select HAVE_GENERIC_DMA_COHERENT
+ select HAVE_DEBUG_STACKOVERFLOW
+ select KMAP_LOCAL
select MODULES_USE_ELF_REL
select OLD_SIGACTION
+ select ARCH_SPLIT_ARG64
config X86_64
def_bool y
depends on 64BIT
# Options that are inherently 64-bit kernel only:
- select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
- select ARCH_SUPPORTS_INT128
- select ARCH_USE_CMPXCHG_LOCKREF
+ select ARCH_HAS_GIGANTIC_PAGE
+ select ARCH_SUPPORTS_MSEAL_SYSTEM_MAPPINGS
+ select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
+ select ARCH_SUPPORTS_PER_VMA_LOCK
+ select ARCH_SUPPORTS_HUGE_PFNMAP if TRANSPARENT_HUGEPAGE
select HAVE_ARCH_SOFT_DIRTY
select MODULES_USE_ELF_RELA
select NEED_DMA_MAP_STATE
select SWIOTLB
- select X86_DEV_DMA_OPS
- select ARCH_HAS_SYSCALL_WRAPPER
+ select ARCH_HAS_ELFCORE_COMPAT
+ select ZONE_DMA32
+ select EXECMEM if DYNAMIC_FTRACE
+ select ACPI_MRRM if ACPI
+config FORCE_DYNAMIC_FTRACE
+ def_bool y
+ depends on X86_32
+ depends on FUNCTION_TRACER
+ select DYNAMIC_FTRACE
+ help
+ We keep the static function tracing (!DYNAMIC_FTRACE) around
+ in order to test the non static function tracing in the
+ generic code, as other architectures still use it. But we
+ only need to keep it around for x86_64. No need to keep it
+ for x86_32. For x86_32, force DYNAMIC_FTRACE.
#
# Arch settings
#
@@ -46,59 +62,114 @@ config X86
#
select ACPI_LEGACY_TABLES_LOOKUP if ACPI
select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI
- select ANON_INODES
- select ARCH_CLOCKSOURCE_DATA
+ select ACPI_HOTPLUG_CPU if ACPI_PROCESSOR && HOTPLUG_CPU
+ select ARCH_32BIT_OFF_T if X86_32
select ARCH_CLOCKSOURCE_INIT
- select ARCH_DISCARD_MEMBLOCK
+ select ARCH_CONFIGURES_CPU_MITIGATIONS
+ select ARCH_CORRECT_STACKTRACE_ON_KRETPROBE
+ select ARCH_ENABLE_HUGEPAGE_MIGRATION if X86_64 && HUGETLB_PAGE && MIGRATION
+ select ARCH_ENABLE_MEMORY_HOTPLUG if X86_64
+ select ARCH_ENABLE_MEMORY_HOTREMOVE if MEMORY_HOTPLUG
+ select ARCH_ENABLE_SPLIT_PMD_PTLOCK if (PGTABLE_LEVELS > 2) && (X86_64 || X86_PAE)
+ select ARCH_ENABLE_THP_MIGRATION if X86_64 && TRANSPARENT_HUGEPAGE
select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI
+ select ARCH_HAS_CPU_ATTACK_VECTORS if CPU_MITIGATIONS
+ select ARCH_HAS_CACHE_LINE_SIZE
+ select ARCH_HAS_CPU_CACHE_INVALIDATE_MEMREGION
+ select ARCH_HAS_CPU_FINALIZE_INIT
+ select ARCH_HAS_CPU_PASID if IOMMU_SVA
+ select ARCH_HAS_CURRENT_STACK_POINTER
select ARCH_HAS_DEBUG_VIRTUAL
+ select ARCH_HAS_DEBUG_VM_PGTABLE if !X86_PAE
select ARCH_HAS_DEVMEM_IS_ALLOWED
+ select ARCH_HAS_DMA_OPS if GART_IOMMU || XEN
+ select ARCH_HAS_EARLY_DEBUG if KGDB
select ARCH_HAS_ELF_RANDOMIZE
+ select ARCH_HAS_EXECMEM_ROX if X86_64 && STRICT_MODULE_RWX
select ARCH_HAS_FAST_MULTIPLIER
- select ARCH_HAS_FILTER_PGPROT
select ARCH_HAS_FORTIFY_SOURCE
select ARCH_HAS_GCOV_PROFILE_ALL
select ARCH_HAS_KCOV if X86_64
+ select ARCH_HAS_KERNEL_FPU_SUPPORT
+ select ARCH_HAS_MEM_ENCRYPT
select ARCH_HAS_MEMBARRIER_SYNC_CORE
+ select ARCH_HAS_NMI_SAFE_THIS_CPU_OPS
+ select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
select ARCH_HAS_PMEM_API if X86_64
+ select ARCH_HAS_PREEMPT_LAZY
+ select ARCH_HAS_PTDUMP
select ARCH_HAS_PTE_SPECIAL
- select ARCH_HAS_REFCOUNT
+ select ARCH_HAS_HW_PTE_YOUNG
+ select ARCH_HAS_NONLEAF_PMD_YOUNG if PGTABLE_LEVELS > 2
select ARCH_HAS_UACCESS_FLUSHCACHE if X86_64
- select ARCH_HAS_UACCESS_MCSAFE if X86_64 && X86_MCE
+ select ARCH_HAS_COPY_MC if X86_64
select ARCH_HAS_SET_MEMORY
+ select ARCH_HAS_SET_DIRECT_MAP
select ARCH_HAS_STRICT_KERNEL_RWX
select ARCH_HAS_STRICT_MODULE_RWX
select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE
- select ARCH_HAS_UBSAN_SANITIZE_ALL
- select ARCH_HAS_ZONE_DEVICE if X86_64
+ select ARCH_HAS_SYSCALL_WRAPPER
+ select ARCH_HAS_UBSAN
+ select ARCH_HAS_DEBUG_WX
+ select ARCH_HAS_ZONE_DMA_SET if EXPERT
select ARCH_HAVE_NMI_SAFE_CMPXCHG
+ select ARCH_HAVE_EXTRA_ELF_NOTES
+ select ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE
select ARCH_MIGHT_HAVE_ACPI_PDC if ACPI
select ARCH_MIGHT_HAVE_PC_PARPORT
select ARCH_MIGHT_HAVE_PC_SERIO
+ select ARCH_STACKWALK
select ARCH_SUPPORTS_ACPI
select ARCH_SUPPORTS_ATOMIC_RMW
+ select ARCH_SUPPORTS_DEBUG_PAGEALLOC
+ select ARCH_SUPPORTS_HUGETLBFS
+ select ARCH_SUPPORTS_PAGE_TABLE_CHECK if X86_64
select ARCH_SUPPORTS_NUMA_BALANCING if X86_64
+ select ARCH_SUPPORTS_KMAP_LOCAL_FORCE_MAP if NR_CPUS <= 4096
+ select ARCH_SUPPORTS_CFI if X86_64
+ select ARCH_USES_CFI_TRAPS if X86_64 && CFI
+ select ARCH_SUPPORTS_LTO_CLANG
+ select ARCH_SUPPORTS_LTO_CLANG_THIN
+ select ARCH_SUPPORTS_RT
+ select ARCH_SUPPORTS_AUTOFDO_CLANG
+ select ARCH_SUPPORTS_PROPELLER_CLANG if X86_64
select ARCH_USE_BUILTIN_BSWAP
+ select ARCH_USE_CMPXCHG_LOCKREF if X86_CX8
+ select ARCH_USE_MEMTEST
select ARCH_USE_QUEUED_RWLOCKS
select ARCH_USE_QUEUED_SPINLOCKS
+ select ARCH_USE_SYM_ANNOTATIONS
select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
+ select ARCH_WANT_DEFAULT_BPF_JIT if X86_64
select ARCH_WANTS_DYNAMIC_TASK_STRUCT
+ select ARCH_WANTS_NO_INSTR
+ select ARCH_WANT_GENERAL_HUGETLB
+ select ARCH_WANT_HUGE_PMD_SHARE if X86_64
+ select ARCH_WANT_LD_ORPHAN_WARN
+ select ARCH_WANT_OPTIMIZE_DAX_VMEMMAP if X86_64
+ select ARCH_WANT_OPTIMIZE_HUGETLB_VMEMMAP if X86_64
+ select ARCH_WANT_HUGETLB_VMEMMAP_PREINIT if X86_64
select ARCH_WANTS_THP_SWAP if X86_64
- select BUILDTIME_EXTABLE_SORT
+ select ARCH_HAS_PARANOID_L1D_FLUSH
+ select ARCH_WANT_IRQS_OFF_ACTIVATE_MM
+ select BUILDTIME_TABLE_SORT
select CLKEVT_I8253
- select CLOCKSOURCE_VALIDATE_LAST_CYCLE
select CLOCKSOURCE_WATCHDOG
- select DCACHE_WORD_ACCESS
+ # Word-size accesses may read uninitialized data past the trailing \0
+ # in strings and cause false KMSAN reports.
+ select DCACHE_WORD_ACCESS if !KMSAN
+ select DYNAMIC_SIGFRAME
select EDAC_ATOMIC_SCRUB
select EDAC_SUPPORT
- select GENERIC_CLOCKEVENTS
select GENERIC_CLOCKEVENTS_BROADCAST if X86_64 || (X86_32 && X86_LOCAL_APIC)
+ select GENERIC_CLOCKEVENTS_BROADCAST_IDLE if GENERIC_CLOCKEVENTS_BROADCAST
select GENERIC_CLOCKEVENTS_MIN_ADJUST
select GENERIC_CMOS_UPDATE
select GENERIC_CPU_AUTOPROBE
+ select GENERIC_CPU_DEVICES
select GENERIC_CPU_VULNERABILITIES
select GENERIC_EARLY_IOREMAP
- select GENERIC_FIND_FIRST_BIT
+ select GENERIC_ENTRY
select GENERIC_IOMAP
select GENERIC_IRQ_EFFECTIVE_AFF_MASK if SMP
select GENERIC_IRQ_MATRIX_ALLOCATOR if X86_LOCAL_APIC
@@ -108,74 +179,101 @@ config X86
select GENERIC_IRQ_SHOW
select GENERIC_PENDING_IRQ if SMP
select GENERIC_SMP_IDLE_THREAD
- select GENERIC_STRNCPY_FROM_USER
- select GENERIC_STRNLEN_USER
select GENERIC_TIME_VSYSCALL
+ select GENERIC_GETTIMEOFDAY
+ select GENERIC_VDSO_OVERFLOW_PROTECT
+ select GUP_GET_PXX_LOW_HIGH if X86_PAE
+ select HARDIRQS_SW_RESEND
select HARDLOCKUP_CHECK_TIMESTAMP if X86_64
+ select HAS_IOPORT
select HAVE_ACPI_APEI if ACPI
select HAVE_ACPI_APEI_NMI if ACPI
- select HAVE_ALIGNED_STRUCT_PAGE if SLUB
+ select HAVE_ALIGNED_STRUCT_PAGE
select HAVE_ARCH_AUDITSYSCALL
select HAVE_ARCH_HUGE_VMAP if X86_64 || X86_PAE
+ select HAVE_ARCH_HUGE_VMALLOC if X86_64
select HAVE_ARCH_JUMP_LABEL
select HAVE_ARCH_JUMP_LABEL_RELATIVE
select HAVE_ARCH_KASAN if X86_64
+ select HAVE_ARCH_KASAN_VMALLOC if X86_64
+ select HAVE_ARCH_KFENCE
+ select HAVE_ARCH_KMSAN if X86_64
select HAVE_ARCH_KGDB
+ select HAVE_ARCH_KSTACK_ERASE
select HAVE_ARCH_MMAP_RND_BITS if MMU
select HAVE_ARCH_MMAP_RND_COMPAT_BITS if MMU && COMPAT
select HAVE_ARCH_COMPAT_MMAP_BASES if MMU && COMPAT
select HAVE_ARCH_PREL32_RELOCATIONS
select HAVE_ARCH_SECCOMP_FILTER
select HAVE_ARCH_THREAD_STRUCT_WHITELIST
- select HAVE_ARCH_STACKLEAK
select HAVE_ARCH_TRACEHOOK
select HAVE_ARCH_TRANSPARENT_HUGEPAGE
select HAVE_ARCH_TRANSPARENT_HUGEPAGE_PUD if X86_64
+ select HAVE_ARCH_USERFAULTFD_WP if X86_64 && USERFAULTFD
+ select HAVE_ARCH_USERFAULTFD_MINOR if X86_64 && USERFAULTFD
select HAVE_ARCH_VMAP_STACK if X86_64
+ select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET
select HAVE_ARCH_WITHIN_STACK_FRAMES
+ select HAVE_ASM_MODVERSIONS
select HAVE_CMPXCHG_DOUBLE
select HAVE_CMPXCHG_LOCAL
- select HAVE_CONTEXT_TRACKING if X86_64
- select HAVE_COPY_THREAD_TLS
+ select HAVE_CONTEXT_TRACKING_USER if X86_64
+ select HAVE_CONTEXT_TRACKING_USER_OFFSTACK if HAVE_CONTEXT_TRACKING_USER
select HAVE_C_RECORDMCOUNT
+ select HAVE_OBJTOOL_MCOUNT if HAVE_OBJTOOL
+ select HAVE_OBJTOOL_NOP_MCOUNT if HAVE_OBJTOOL_MCOUNT
+ select HAVE_BUILDTIME_MCOUNT_SORT
select HAVE_DEBUG_KMEMLEAK
- select HAVE_DEBUG_STACKOVERFLOW
select HAVE_DMA_CONTIGUOUS
select HAVE_DYNAMIC_FTRACE
select HAVE_DYNAMIC_FTRACE_WITH_REGS
+ select HAVE_DYNAMIC_FTRACE_WITH_ARGS if X86_64
+ select HAVE_FTRACE_REGS_HAVING_PT_REGS if X86_64
+ select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS
+ select HAVE_DYNAMIC_FTRACE_WITH_JMP if X86_64
+ select HAVE_SAMPLE_FTRACE_DIRECT if X86_64
+ select HAVE_SAMPLE_FTRACE_DIRECT_MULTI if X86_64
select HAVE_EBPF_JIT
select HAVE_EFFICIENT_UNALIGNED_ACCESS
- select HAVE_EISA
+ select HAVE_EISA if X86_32
select HAVE_EXIT_THREAD
+ select HAVE_GENERIC_TIF_BITS
+ select HAVE_GUP_FAST
select HAVE_FENTRY if X86_64 || DYNAMIC_FTRACE
- select HAVE_FTRACE_MCOUNT_RECORD
- select HAVE_FUNCTION_GRAPH_TRACER
+ select HAVE_FTRACE_GRAPH_FUNC if HAVE_FUNCTION_GRAPH_TRACER
+ select HAVE_FUNCTION_GRAPH_FREGS if HAVE_FUNCTION_GRAPH_TRACER
+ select HAVE_FUNCTION_GRAPH_TRACER if X86_32 || (X86_64 && DYNAMIC_FTRACE)
select HAVE_FUNCTION_TRACER
select HAVE_GCC_PLUGINS
select HAVE_HW_BREAKPOINT
- select HAVE_IDE
select HAVE_IOREMAP_PROT
select HAVE_IRQ_EXIT_ON_IRQ_STACK if X86_64
select HAVE_IRQ_TIME_ACCOUNTING
+ select HAVE_JUMP_LABEL_HACK if HAVE_OBJTOOL
select HAVE_KERNEL_BZIP2
select HAVE_KERNEL_GZIP
select HAVE_KERNEL_LZ4
select HAVE_KERNEL_LZMA
select HAVE_KERNEL_LZO
select HAVE_KERNEL_XZ
+ select HAVE_KERNEL_ZSTD
select HAVE_KPROBES
select HAVE_KPROBES_ON_FTRACE
select HAVE_FUNCTION_ERROR_INJECTION
select HAVE_KRETPROBES
- select HAVE_KVM
+ select HAVE_RETHOOK
+ select HAVE_KLP_BUILD if X86_64
select HAVE_LIVEPATCH if X86_64
- select HAVE_MEMBLOCK_NODE_MAP
select HAVE_MIXED_BREAKPOINTS_REGS
select HAVE_MOD_ARCH_SPECIFIC
select HAVE_MOVE_PMD
+ select HAVE_MOVE_PUD
+ select HAVE_NOINSTR_HACK if HAVE_OBJTOOL
select HAVE_NMI
- select HAVE_OPROFILE
+ select HAVE_NOINSTR_VALIDATION if HAVE_OBJTOOL
+ select HAVE_OBJTOOL if X86_64
select HAVE_OPTPROBES
+ select HAVE_PAGE_SIZE_4KB
select HAVE_PCSPKR_PLATFORM
select HAVE_PERF_EVENTS
select HAVE_PERF_EVENTS_NMI
@@ -183,32 +281,61 @@ config X86
select HAVE_PCI
select HAVE_PERF_REGS
select HAVE_PERF_USER_STACK_DUMP
- select HAVE_RCU_TABLE_FREE if PARAVIRT
- select HAVE_RCU_TABLE_INVALIDATE if HAVE_RCU_TABLE_FREE
+ select ASYNC_KERNEL_PGTABLE_FREE if IOMMU_SVA
+ select MMU_GATHER_RCU_TABLE_FREE
+ select MMU_GATHER_MERGE_VMAS
+ select HAVE_POSIX_CPU_TIMERS_TASK_WORK
select HAVE_REGS_AND_STACK_ACCESS_API
- select HAVE_RELIABLE_STACKTRACE if X86_64 && (UNWINDER_FRAME_POINTER || UNWINDER_ORC) && STACK_VALIDATION
+ select HAVE_RELIABLE_STACKTRACE if UNWINDER_ORC || STACK_VALIDATION
select HAVE_FUNCTION_ARG_ACCESS_API
- select HAVE_STACKPROTECTOR if CC_HAS_SANE_STACKPROTECTOR
- select HAVE_STACK_VALIDATION if X86_64
+ select HAVE_SETUP_PER_CPU_AREA
+ select HAVE_SOFTIRQ_ON_OWN_STACK
+ select HAVE_STACKPROTECTOR
+ select HAVE_STACK_VALIDATION if HAVE_OBJTOOL
+ select HAVE_STATIC_CALL
+ select HAVE_STATIC_CALL_INLINE if HAVE_OBJTOOL
+ select HAVE_PREEMPT_DYNAMIC_CALL
select HAVE_RSEQ
+ select HAVE_RUST if X86_64
select HAVE_SYSCALL_TRACEPOINTS
+ select HAVE_UACCESS_VALIDATION if HAVE_OBJTOOL
select HAVE_UNSTABLE_SCHED_CLOCK
+ select HAVE_UNWIND_USER_FP if X86_64
select HAVE_USER_RETURN_NOTIFIER
+ select HAVE_GENERIC_VDSO
+ select VDSO_GETRANDOM if X86_64
+ select HOTPLUG_PARALLEL if SMP && X86_64
select HOTPLUG_SMT if SMP
+ select HOTPLUG_SPLIT_STARTUP if SMP && X86_32
select IRQ_FORCED_THREADING
+ select LOCK_MM_AND_FIND_VMA
+ select NEED_PER_CPU_EMBED_FIRST_CHUNK
+ select NEED_PER_CPU_PAGE_FIRST_CHUNK
select NEED_SG_DMA_LENGTH
+ select NUMA_MEMBLKS if NUMA
select PCI_DOMAINS if PCI
- select PCI_LOCKLESS_CONFIG
+ select PCI_LOCKLESS_CONFIG if PCI
select PERF_EVENTS
select RTC_LIB
select RTC_MC146818_LIB
select SPARSE_IRQ
- select SRCU
select SYSCTL_EXCEPTION_TRACE
select THREAD_INFO_IN_TASK
+ select TRACE_IRQFLAGS_SUPPORT
+ select TRACE_IRQFLAGS_NMI_SUPPORT
select USER_STACKTRACE_SUPPORT
- select VIRT_TO_BUS
- select X86_FEATURE_NAMES if PROC_FS
+ select HAVE_ARCH_KCSAN if X86_64
+ select PROC_PID_ARCH_STATUS if PROC_FS
+ select HAVE_ARCH_NODE_DEV_GROUP if X86_SGX
+ select FUNCTION_ALIGNMENT_16B if X86_64 || X86_ALIGNMENT_16
+ select FUNCTION_ALIGNMENT_4B
+ imply IMA_SECURE_AND_OR_TRUSTED_BOOT if EFI
+ select HAVE_DYNAMIC_FTRACE_NO_PATCHABLE
+ select ARCH_SUPPORTS_PT_RECLAIM if X86_64
+ select ARCH_SUPPORTS_SCHED_SMT if SMP
+ select SCHED_SMT if SMP
+ select ARCH_SUPPORTS_SCHED_CLUSTER if SMP
+ select ARCH_SUPPORTS_SCHED_MC if SMP
config INSTRUCTION_DECODER
def_bool y
@@ -219,11 +346,6 @@ config OUTPUT_FORMAT
default "elf32-i386" if X86_32
default "elf64-x86-64" if X86_64
-config ARCH_DEFCONFIG
- string
- default "arch/x86/configs/i386_defconfig" if X86_32
- default "arch/x86/configs/x86_64_defconfig" if X86_64
-
config LOCKDEP_SUPPORT
def_bool y
@@ -254,69 +376,37 @@ config GENERIC_ISA_DMA
def_bool y
depends on ISA_DMA_API
+config GENERIC_CSUM
+ bool
+ default y if KMSAN || KASAN
+
config GENERIC_BUG
def_bool y
depends on BUG
- select GENERIC_BUG_RELATIVE_POINTERS if X86_64
+ select GENERIC_BUG_RELATIVE_POINTERS
config GENERIC_BUG_RELATIVE_POINTERS
bool
-config GENERIC_HWEIGHT
- def_bool y
-
config ARCH_MAY_HAVE_PC_FDC
def_bool y
depends on ISA_DMA_API
-config RWSEM_XCHGADD_ALGORITHM
- def_bool y
-
config GENERIC_CALIBRATE_DELAY
def_bool y
config ARCH_HAS_CPU_RELAX
def_bool y
-config ARCH_HAS_CACHE_LINE_SIZE
- def_bool y
-
-config ARCH_HAS_FILTER_PGPROT
- def_bool y
-
-config HAVE_SETUP_PER_CPU_AREA
- def_bool y
-
-config NEED_PER_CPU_EMBED_FIRST_CHUNK
- def_bool y
-
-config NEED_PER_CPU_PAGE_FIRST_CHUNK
- def_bool y
-
config ARCH_HIBERNATION_POSSIBLE
def_bool y
config ARCH_SUSPEND_POSSIBLE
def_bool y
-config ARCH_WANT_HUGE_PMD_SHARE
- def_bool y
-
-config ARCH_WANT_GENERAL_HUGETLB
- def_bool y
-
-config ZONE_DMA32
- def_bool y if X86_64
-
config AUDIT_ARCH
def_bool y if X86_64
-config ARCH_SUPPORTS_OPTIMIZED_INLINING
- def_bool y
-
-config ARCH_SUPPORTS_DEBUG_PAGEALLOC
- def_bool y
-
config KASAN_SHADOW_OFFSET
hex
depends on KASAN
@@ -326,18 +416,6 @@ config HAVE_INTEL_TXT
def_bool y
depends on INTEL_IOMMU && ACPI
-config X86_32_SMP
- def_bool y
- depends on X86_32 && SMP
-
-config X86_64_SMP
- def_bool y
- depends on X86_64 && SMP
-
-config X86_32_LAZY_GS
- def_bool y
- depends on X86_32 && !STACKPROTECTOR
-
config ARCH_SUPPORTS_UPROBES
def_bool y
@@ -349,34 +427,15 @@ config DYNAMIC_PHYSICAL_MASK
config PGTABLE_LEVELS
int
- default 5 if X86_5LEVEL
- default 4 if X86_64
+ default 5 if X86_64
default 3 if X86_PAE
default 2
-config CC_HAS_SANE_STACKPROTECTOR
- bool
- default $(success,$(srctree)/scripts/gcc-x86_64-has-stack-protector.sh $(CC)) if 64BIT
- default $(success,$(srctree)/scripts/gcc-x86_32-has-stack-protector.sh $(CC))
- help
- We have to make sure stack protector is unconditionally disabled if
- the compiler produces broken code.
-
menu "Processor type and features"
-config ZONE_DMA
- bool "DMA memory allocation support" if EXPERT
- default y
- help
- DMA memory allocation support allows devices with less than 32-bit
- addressing to allocate within the first 16MB of address space.
- Disable if no such devices will be used.
-
- If unsure, say Y.
-
config SMP
bool "Symmetric multi-processing support"
- ---help---
+ help
This enables support for systems with more than one CPU. If you have
a system with only one CPU, say N. If you have a system with more
than one CPU, say Y.
@@ -396,62 +455,77 @@ config SMP
Y to "Enhanced Real Time Clock Support", below. The "Advanced Power
Management" code will be disabled if you say Y here.
- See also <file:Documentation/x86/i386/IO-APIC.txt>,
- <file:Documentation/lockup-watchdogs.txt> and the SMP-HOWTO available at
+ See also <file:Documentation/arch/x86/i386/IO-APIC.rst>,
+ <file:Documentation/admin-guide/lockup-watchdogs.rst> and the SMP-HOWTO available at
<http://www.tldp.org/docs.html#howto>.
If you don't know what to do here, say N.
-config X86_FEATURE_NAMES
- bool "Processor feature human-readable names" if EMBEDDED
+config X86_X2APIC
+ bool "x2APIC interrupt controller architecture support"
+ depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
default y
- ---help---
- This option compiles in a table of x86 feature bits and corresponding
- names. This is required to support /proc/cpuinfo and a few kernel
- messages. You can disable this to save space, at the expense of
- making those few kernel messages show numeric feature bits instead.
+ help
+ x2APIC is an interrupt controller architecture, a component of which
+ (the local APIC) is present in the CPU. It allows faster access to
+ the local APIC and supports a larger number of CPUs in the system
+ than the predecessors.
+
+ x2APIC was introduced in Intel CPUs around 2008 and in AMD EPYC CPUs
+ in 2019, but it can be disabled by the BIOS. It is also frequently
+ emulated in virtual machines, even when the host CPU does not support
+ it. Support in the CPU can be checked by executing
+ grep x2apic /proc/cpuinfo
+
+ If this configuration option is disabled, the kernel will boot with
+ very reduced functionality and performance on some platforms that
+ have x2APIC enabled. On the other hand, on hardware that does not
+ support x2APIC, a kernel with this option enabled will just fallback
+ to older APIC implementations.
If in doubt, say Y.
-config X86_X2APIC
- bool "Support x2apic"
- depends on X86_LOCAL_APIC && X86_64 && (IRQ_REMAP || HYPERVISOR_GUEST)
- ---help---
- This enables x2apic support on CPUs that have this feature.
+config AMD_SECURE_AVIC
+ bool "AMD Secure AVIC"
+ depends on AMD_MEM_ENCRYPT && X86_X2APIC
+ help
+ Enable this to get AMD Secure AVIC support on guests that have this feature.
- This allows 32-bit apic IDs (so it can support very large systems),
- and accesses the local apic via MSRs not via mmio.
+ AMD Secure AVIC provides hardware acceleration for performance sensitive
+ APIC accesses and support for managing guest owned APIC state for SEV-SNP
+ guests. Secure AVIC does not support xAPIC mode. It has functional
+ dependency on x2apic being enabled in the guest.
+
+ If you don't know what to do here, say N.
+
+config X86_POSTED_MSI
+ bool "Enable MSI and MSI-x delivery by posted interrupts"
+ depends on X86_64 && IRQ_REMAP
+ help
+ This enables MSIs that are under interrupt remapping to be delivered as
+ posted interrupts to the host kernel. Interrupt throughput can
+ potentially be improved by coalescing CPU notifications during high
+ frequency bursts.
If you don't know what to do here, say N.
config X86_MPPARSE
- bool "Enable MPS table" if ACPI || SFI
+ bool "Enable MPS table" if ACPI
default y
depends on X86_LOCAL_APIC
- ---help---
+ help
For old smp systems that do not have proper acpi support. Newer systems
(esp with 64bit cpus) with acpi support, MADT and DSDT will override it
-config GOLDFISH
- def_bool y
- depends on X86_GOLDFISH
-
-config RETPOLINE
- bool "Avoid speculative indirect branches in kernel"
- default y
- select STACK_VALIDATION if HAVE_STACK_VALIDATION
- help
- Compile kernel with the retpoline compiler options to guard against
- kernel-to-user data leaks by avoiding speculative indirect
- branches. Requires a compiler with -mindirect-branch=thunk-extern
- support for full protection. The kernel may run slower.
-
-config X86_RESCTRL
- bool "Resource Control support"
+config X86_CPU_RESCTRL
+ bool "x86 CPU resource control support"
depends on X86 && (CPU_SUP_INTEL || CPU_SUP_AMD)
- select KERNFS
+ depends on MISC_FILESYSTEMS
+ select ARCH_HAS_CPU_RESCTRL
+ select RESCTRL_FS
+ select RESCTRL_FS_PSEUDO_LOCK
help
- Enable Resource Control support.
+ Enable x86 CPU resource control support.
Provide support for the allocation and monitoring of system resources
usage by the CPU.
@@ -466,52 +540,43 @@ config X86_RESCTRL
Say N if unsure.
-if X86_32
-config X86_BIGSMP
- bool "Support for big SMP systems with more than 8 CPUs"
- depends on SMP
- ---help---
- This option is needed for the systems that have more than 8 CPUs
+config X86_FRED
+ bool "Flexible Return and Event Delivery"
+ depends on X86_64
+ help
+ When enabled, try to use Flexible Return and Event Delivery
+ instead of the legacy SYSCALL/SYSENTER/IDT architecture for
+ ring transitions and exception/interrupt handling if the
+ system supports it.
config X86_EXTENDED_PLATFORM
bool "Support for extended (non-PC) x86 platforms"
default y
- ---help---
+ help
If you disable this option then the kernel will only support
standard PC platforms. (which covers the vast majority of
systems out there.)
If you enable this option then you'll be able to select support
- for the following (non-PC) 32 bit x86 platforms:
- Goldfish (Android emulator)
- AMD Elan
- RDC R-321x SoC
- SGI 320/540 (Visual Workstation)
- STA2X11-based (e.g. Northville)
- Moorestown MID devices
-
- If you have one of these systems, or if you want to build a
- generic distribution kernel, say Y here - otherwise say N.
-endif
+ for the following non-PC x86 platforms, depending on the value of
+ CONFIG_64BIT.
-if X86_64
-config X86_EXTENDED_PLATFORM
- bool "Support for extended (non-PC) x86 platforms"
- 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.)
+ 32-bit platforms (CONFIG_64BIT=n):
+ Goldfish (mostly Android emulator)
+ Intel CE media processor (CE4100) SoC
+ Intel Quark
+ RDC R-321x SoC
- If you enable this option then you'll be able to select support
- for the following (non-PC) 64 bit x86 platforms:
+ 64-bit platforms (CONFIG_64BIT=y):
Numascale NumaChip
ScaleMP vSMP
SGI Ultraviolet
+ Merrifield/Moorefield MID devices
+ Goldfish (mostly Android emulator)
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
@@ -522,7 +587,7 @@ config X86_NUMACHIP
depends on SMP
depends on X86_X2APIC
depends on PCI_MMCONFIG
- ---help---
+ 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.
@@ -534,7 +599,7 @@ config X86_VSMP
depends on X86_64 && PCI
depends on X86_EXTENDED_PLATFORM
depends on SMP
- ---help---
+ 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.
@@ -545,22 +610,49 @@ config X86_UV
depends on X86_EXTENDED_PLATFORM
depends on NUMA
depends on EFI
+ depends on KEXEC_CORE
depends on X86_X2APIC
depends on PCI
- ---help---
+ 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_INTEL_MID
+ bool "Intel Z34xx/Z35xx MID platform support"
+ depends on X86_EXTENDED_PLATFORM
+ depends on X86_PLATFORM_DEVICES
+ depends on PCI
+ depends on X86_64 || (EXPERT && PCI_GOANY)
+ depends on X86_IO_APIC
+ select I2C
+ select DW_APB_TIMER
+ select INTEL_SCU_PCI
+ help
+ Select to build a kernel capable of supporting 64-bit Intel MID
+ (Mobile Internet Device) platform systems which do not have
+ the PCI legacy interfaces.
+
+ The only supported devices are the 22nm Merrified (Z34xx)
+ and Moorefield (Z35xx) SoC used in the Intel Edison board and
+ a small number of Android devices such as the Asus Zenfone 2,
+ Asus FonePad 8 and Dell Venue 7.
+
+ If you are building for a PC class system or non-MID tablet
+ SoCs like Bay Trail (Z36xx/Z37xx), 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_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.
+ 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.
+
+# Following is an alphabetically sorted list of 32 bit extended platforms
+# Please maintain the alphabetic order if and when there are additions
config X86_INTEL_CE
bool "CE4100 TV platform"
@@ -572,32 +664,11 @@ config X86_INTEL_CE
select X86_REBOOTFIXUPS
select OF
select OF_EARLY_FLATTREE
- ---help---
+ 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 SFI
- select I2C
- select DW_APB_TIMER
- select APB_TIMER
- select INTEL_SCU_IPC
- 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
@@ -610,18 +681,29 @@ config X86_INTEL_QUARK
select IOSF_MBI
select INTEL_IMR
select COMMON_CLK
- ---help---
+ 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_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_INTEL_LPSS
bool "Intel Low Power Subsystem Support"
depends on X86 && ACPI && PCI
select COMMON_CLK
select PINCTRL
select IOSF_MBI
- ---help---
+ 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
@@ -632,7 +714,7 @@ config X86_AMD_PLATFORM_DEVICE
depends on ACPI
select COMMON_CLK
select PINCTRL
- ---help---
+ 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
@@ -641,7 +723,7 @@ config X86_AMD_PLATFORM_DEVICE
config IOSF_MBI
tristate "Intel SoC IOSF Sideband support for SoC platforms"
depends on PCI
- ---help---
+ 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
@@ -658,7 +740,7 @@ config IOSF_MBI
config IOSF_MBI_DEBUG
bool "Enable IOSF sideband access through debugfs"
depends on IOSF_MBI && DEBUG_FS
- ---help---
+ 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
@@ -668,29 +750,6 @@ config IOSF_MBI_DEBUG
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():
@@ -700,26 +759,10 @@ config X86_SUPPORTS_MEMORY_FAILURE
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 ARCH_HAS_PHYS_TO_DMA
- select X86_DEV_DMA_OPS
- select X86_DMA_REMAP
- 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---
+ 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
@@ -733,7 +776,7 @@ config SCHED_OMIT_FRAME_POINTER
def_bool y
prompt "Single-depth WCHAN output"
depends on X86
- ---help---
+ 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,
@@ -743,7 +786,7 @@ config SCHED_OMIT_FRAME_POINTER
menuconfig HYPERVISOR_GUEST
bool "Linux guest support"
- ---help---
+ help
Say Y here to enable options for running Linux under various hyper-
visors. This option enables basic hypervisor detection and platform
setup.
@@ -755,7 +798,8 @@ if HYPERVISOR_GUEST
config PARAVIRT
bool "Enable paravirtualization code"
- ---help---
+ depends on HAVE_STATIC_CALL
+ 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
@@ -763,18 +807,19 @@ config PARAVIRT
config PARAVIRT_XXL
bool
+ depends on X86_64
config PARAVIRT_DEBUG
bool "paravirt-ops debugging"
depends on PARAVIRT && DEBUG_KERNEL
- ---help---
+ 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---
+ 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).
@@ -784,13 +829,8 @@ config PARAVIRT_SPINLOCKS
If you are unsure how to answer this question, answer Y.
-config QUEUED_LOCK_STAT
- bool "Paravirt queued spinlock statistics"
- depends on PARAVIRT_SPINLOCKS && DEBUG_FS
- ---help---
- Enable the collection of statistical data on the slowpath
- behavior of paravirtualized queued spinlocks and report
- them on debugfs.
+config X86_HV_CALLBACK_VECTOR
+ def_bool n
source "arch/x86/xen/Kconfig"
@@ -798,32 +838,32 @@ 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---
+ 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---
+ help
This option enables the PVH entry point for guest virtual machines
as specified in the x86/HVM direct boot ABI.
-config KVM_DEBUG_FS
- bool "Enable debug information for KVM Guests in debugfs"
- depends on KVM_GUEST && DEBUG_FS
- ---help---
- This option enables collection of various statistics for KVM guest.
- Statistics are displayed in debugfs filesystem. Enabling this option
- may incur significant overhead.
-
config PARAVIRT_TIME_ACCOUNTING
bool "Paravirtual steal time accounting"
depends on PARAVIRT
- ---help---
+ 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
@@ -838,19 +878,57 @@ config JAILHOUSE_GUEST
bool "Jailhouse non-root cell support"
depends on X86_64 && PCI
select X86_PM_TIMER
- ---help---
+ 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.
-endif #HYPERVISOR_GUEST
+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/.
+
+config BHYVE_GUEST
+ bool "Bhyve (BSD Hypervisor) Guest support"
+ depends on X86_64
+ help
+ This option allows to run Linux to recognise when it is running as a
+ guest in the Bhyve hypervisor, and to support more than 255 vCPUs when
+ when doing so. More details about Bhyve can be found at https://bhyve.org
+ and https://wiki.freebsd.org/bhyve/.
+
+config INTEL_TDX_GUEST
+ bool "Intel TDX (Trust Domain Extensions) - Guest Support"
+ depends on X86_64 && CPU_SUP_INTEL
+ depends on X86_X2APIC
+ depends on EFI_STUB
+ depends on PARAVIRT
+ select ARCH_HAS_CC_PLATFORM
+ select X86_MEM_ENCRYPT
+ select X86_MCE
+ select UNACCEPTED_MEMORY
+ help
+ Support running as a guest under Intel TDX. Without this support,
+ the guest kernel can not boot or run under TDX.
+ TDX includes memory encryption and integrity capabilities
+ which protect the confidentiality and integrity of guest
+ memory contents and CPU state. TDX guests are protected from
+ some attacks from the VMM.
+
+endif # HYPERVISOR_GUEST
source "arch/x86/Kconfig.cpu"
config HPET_TIMER
def_bool X86_64
prompt "HPET Timer Support" if X86_32
- ---help---
+ 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.
@@ -868,19 +946,7 @@ config HPET_TIMER
config HPET_EMULATE_RTC
def_bool y
- depends on HPET_TIMER && (RTC=y || RTC=m || RTC_DRV_CMOS=m || RTC_DRV_CMOS=y)
-
-config APB_TIMER
- def_bool y if X86_INTEL_MID
- prompt "Intel MID APB Timer Support" if X86_INTEL_MID
- select DW_APB_TIMER
- depends on X86_INTEL_MID && SFI
- help
- APB timer is the replacement for 8254, HPET on X86 MID platforms.
- The APBT provides a stable time base on SMP
- systems, unlike the TSC, but it is more expensive to access,
- as it is off-chip. APB timers are always running regardless of CPU
- C states, they are used as per CPU clockevent device when possible.
+ 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.
@@ -888,7 +954,7 @@ config DMI
default y
select DMI_SCAN_MACHINE_NON_EFI_FALLBACK
bool "Enable DMI scanning" if EXPERT
- ---help---
+ 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
@@ -899,7 +965,7 @@ config GART_IOMMU
select IOMMU_HELPER
select SWIOTLB
depends on X86_64 && PCI && AMD_NB
- ---help---
+ help
Provides a driver for older AMD Athlon64/Opteron/Turion/Sempron
GART based hardware IOMMUs.
@@ -916,41 +982,17 @@ config GART_IOMMU
If unsure, say Y.
-config CALGARY_IOMMU
- bool "IBM Calgary IOMMU support"
- select IOMMU_HELPER
- select SWIOTLB
- depends on X86_64 && PCI
- ---help---
- Support for hardware IOMMUs in IBM's xSeries x366 and x460
- systems. Needed to run systems with more than 3GB of memory
- properly with 32-bit PCI devices that do not support DAC
- (Double Address Cycle). Calgary also supports bus level
- isolation, where all DMAs pass through the IOMMU. This
- prevents them from going anywhere except their intended
- destination. This catches hard-to-find kernel bugs and
- mis-behaving drivers and devices that do not use the DMA-API
- properly to set up their DMA buffers. The IOMMU can be
- turned off at boot time with the iommu=off parameter.
- Normally the kernel will make the right choice by itself.
- If unsure, say Y.
-
-config CALGARY_IOMMU_ENABLED_BY_DEFAULT
- def_bool y
- prompt "Should Calgary be enabled by default?"
- depends on CALGARY_IOMMU
- ---help---
- Should Calgary be enabled by default? if you choose 'y', Calgary
- will be used (if it exists). If you choose 'n', Calgary will not be
- used even if it exists. If you choose 'n' and would like to use
- Calgary anyway, pass 'iommu=calgary' on the kernel command line.
- If unsure, say Y.
+config BOOT_VESA_SUPPORT
+ bool
+ help
+ If true, at least one selected framebuffer driver can take advantage
+ of VESA video modes set at an early boot stage via the vga= parameter.
config MAXSMP
bool "Enable Maximum number of SMP Processors and NUMA Nodes"
depends on X86_64 && SMP && DEBUG_KERNEL
select CPUMASK_OFFSTACK
- ---help---
+ help
Enable maximum number of CPUS and NUMA Nodes for this architecture.
If unsure, say N.
@@ -977,21 +1019,19 @@ config NR_CPUS_RANGE_BEGIN
config NR_CPUS_RANGE_END
int
depends on X86_32
- default 64 if SMP && X86_BIGSMP
- default 8 if SMP && !X86_BIGSMP
+ default 8 if SMP
default 1 if !SMP
config NR_CPUS_RANGE_END
int
depends on X86_64
- default 8192 if SMP && ( MAXSMP || CPUMASK_OFFSTACK)
- default 512 if SMP && (!MAXSMP && !CPUMASK_OFFSTACK)
+ 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
@@ -1006,7 +1046,7 @@ 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---
+ 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
@@ -1015,25 +1055,14 @@ config NR_CPUS
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
+ depends on SCHED_MC
+ select X86_INTEL_PSTATE if CPU_SUP_INTEL
+ select X86_AMD_PSTATE if CPU_SUP_AMD && ACPI
select CPU_FREQ
default y
- ---help---
+ 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
@@ -1049,14 +1078,14 @@ config SCHED_MC_PRIO
If unsure say Y here.
config UP_LATE_INIT
- def_bool y
- depends on !SMP && X86_LOCAL_APIC
+ 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---
+ depends on X86_32 && !SMP
+ 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
@@ -1069,7 +1098,7 @@ config X86_UP_APIC
config X86_UP_IOAPIC
bool "IO-APIC support on uniprocessors"
depends on X86_UP_APIC
- ---help---
+ 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.
@@ -1080,9 +1109,15 @@ config X86_UP_IOAPIC
config X86_LOCAL_APIC
def_bool y
- depends on X86_64 || SMP || X86_32_NON_STANDARD || X86_UP_APIC || PCI_MSI
+ depends on X86_64 || SMP || X86_UP_APIC || PCI_MSI
select IRQ_DOMAIN_HIERARCHY
- select PCI_MSI_IRQ_DOMAIN if PCI_MSI
+
+config ACPI_MADT_WAKEUP
+ def_bool y
+ depends on X86_64
+ depends on ACPI
+ depends on SMP
+ depends on X86_LOCAL_APIC
config X86_IO_APIC
def_bool y
@@ -1091,7 +1126,7 @@ config X86_IO_APIC
config X86_REROUTE_FOR_BROKEN_BOOT_IRQS
bool "Reroute for broken boot IRQs"
depends on X86_IO_APIC
- ---help---
+ 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
@@ -1115,7 +1150,7 @@ config X86_MCE
bool "Machine Check / overheating reporting"
select GENERIC_ALLOCATOR
default y
- ---help---
+ 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,
@@ -1124,7 +1159,7 @@ config X86_MCE
config X86_MCELOG_LEGACY
bool "Support for deprecated /dev/mcelog character device"
depends on X86_MCE
- ---help---
+ help
Enable support for /dev/mcelog which is needed by the old mcelog
userspace logging daemon. Consider switching to the new generation
rasdaemon solution.
@@ -1133,22 +1168,22 @@ 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.
+ 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.
+ depends on X86_MCE && X86_LOCAL_APIC
+ 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---
+ 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.
@@ -1160,21 +1195,17 @@ config X86_MCE_THRESHOLD
config X86_MCE_INJECT
depends on X86_MCE && X86_LOCAL_APIC && DEBUG_FS
tristate "Machine check injector support"
- ---help---
+ 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.
-config X86_THERMAL_VECTOR
- def_bool y
- depends on X86_MCE_INTEL
-
source "arch/x86/events/Kconfig"
config X86_LEGACY_VM86
bool "Legacy VM86 support"
depends on X86_32
- ---help---
+ help
This option allows user programs to put the CPU into V8086
mode, which is an 80286-era approximation of 16-bit real mode.
@@ -1199,14 +1230,14 @@ config X86_LEGACY_VM86
If unsure, say N here.
config VM86
- bool
- default X86_LEGACY_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---
+ 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
@@ -1221,27 +1252,45 @@ config X86_ESPFIX64
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.
+ 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---
+ 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
@@ -1254,26 +1303,10 @@ config 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---
+ 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
@@ -1288,55 +1321,61 @@ config X86_REBOOTFIXUPS
Say N otherwise.
config MICROCODE
- bool "CPU microcode loading support"
- default y
+ def_bool y
depends on CPU_SUP_AMD || CPU_SUP_INTEL
- select FW_LOADER
- ---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.txt. 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
- select FW_LOADER
- ---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
- select FW_LOADER
- ---help---
- If you select this option, microcode patch loading support for AMD
- processors will be enabled.
+ select CRYPTO_LIB_SHA256 if CPU_SUP_AMD
-config MICROCODE_OLD_INTERFACE
+config MICROCODE_INITRD32
def_bool y
+ depends on MICROCODE && X86_32 && BLK_DEV_INITRD
+
+config MICROCODE_LATE_LOADING
+ bool "Late microcode loading (DANGEROUS)"
+ default n
+ depends on MICROCODE && SMP
+ help
+ Loading microcode late, when the system is up and executing instructions
+ is a tricky business and should be avoided if possible. Just the sequence
+ of synchronizing all cores and SMT threads is one fragile dance which does
+ not guarantee that cores might not softlock after the loading. Therefore,
+ use this at your own risk. Late loading taints the kernel unless the
+ microcode header indicates that it is safe for late loading via the
+ minimal revision check. This minimal revision check can be enforced on
+ the kernel command line with "microcode=force_minrev".
+
+config MICROCODE_LATE_FORCE_MINREV
+ bool "Enforce late microcode loading minimal revision check"
+ default n
+ depends on MICROCODE_LATE_LOADING
+ help
+ To prevent that users load microcode late which modifies already
+ in use features, newer microcode patches have a minimum revision field
+ in the microcode header, which tells the kernel which minimum
+ revision must be active in the CPU to safely load that new microcode
+ late into the running system. If disabled the check will not
+ be enforced but the kernel will be tainted when the minimal
+ revision check fails.
+
+ This minimal revision check can also be controlled via the
+ "microcode=force_minrev" parameter on the kernel command line.
+
+ If unsure say Y.
+
+config MICROCODE_DBG
+ bool "Enable microcode loader debugging"
+ default n
depends on MICROCODE
+ help
+ Enable code which allows for debugging the microcode loader in
+ a guest. Meaning the patch loading is simulated but everything else
+ related to patch parsing and handling is done as on baremetal with
+ the purpose of debugging solely the software side of things.
+
+ You almost certainly want to say n here.
config X86_MSR
tristate "/dev/cpu/*/msr - Model-specific register support"
- ---help---
+ 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.
@@ -1345,21 +1384,17 @@ config X86_MSR
config X86_CPUID
tristate "/dev/cpu/*/cpuid - CPU information support"
- ---help---
+ 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
+config HIGHMEM4G
+ bool "High Memory Support"
depends on X86_32
-
-config NOHIGHMEM
- bool "off"
- ---help---
- Linux can use up to 64 Gigabytes of physical memory on x86 systems.
+ help
+ Linux can use up to 4 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
@@ -1375,44 +1410,15 @@ config NOHIGHMEM
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.)
+ answer "Y" here.
- 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 !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
+ If unsure, say N.
choice
prompt "Memory split" if EXPERT
default VMSPLIT_3G
depends on X86_32
- ---help---
+ help
Select the desired split between kernel and user memory.
If the address range available to the kernel is less than the
@@ -1452,44 +1458,22 @@ config PAGE_OFFSET
depends on X86_32
config HIGHMEM
- def_bool y
- depends on X86_32 && (HIGHMEM64G || HIGHMEM4G)
+ def_bool HIGHMEM4G
config X86_PAE
bool "PAE (Physical Address Extension) Support"
- depends on X86_32 && !HIGHMEM4G
+ depends on X86_32 && X86_HAVE_PAE
select PHYS_ADDR_T_64BIT
- select SWIOTLB
- ---help---
+ 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"
- 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.txt for more
- information.
-
- Say N if unsure.
-
config X86_DIRECT_GBPAGES
def_bool y
- depends on X86_64 && !DEBUG_PAGEALLOC
- ---help---
+ 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
@@ -1498,49 +1482,41 @@ config X86_DIRECT_GBPAGES
config X86_CPA_STATISTICS
bool "Enable statistic for Change Page Attribute"
depends on DEBUG_FS
- ---help---
- Expose statistics about the Change Page Attribute mechanims, which
- helps to determine the effectivness of preserving large and huge
+ 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 ARCH_HAS_MEM_ENCRYPT
- def_bool y
+config X86_MEM_ENCRYPT
+ select ARCH_HAS_FORCE_DMA_UNENCRYPTED
+ select DYNAMIC_PHYSICAL_MASK
+ def_bool n
config AMD_MEM_ENCRYPT
bool "AMD Secure Memory Encryption (SME) support"
depends on X86_64 && CPU_SUP_AMD
- select DYNAMIC_PHYSICAL_MASK
- ---help---
+ depends on EFI_STUB
+ select DMA_COHERENT_POOL
+ select ARCH_USE_MEMREMAP_PROT
+ select INSTRUCTION_DECODER
+ select ARCH_HAS_CC_PLATFORM
+ select X86_MEM_ENCRYPT
+ select UNACCEPTED_MEMORY
+ select CRYPTO_LIB_AESGCM
+ 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.
-
-config ARCH_USE_MEMREMAP_PROT
- def_bool y
- depends on AMD_MEM_ENCRYPT
-
# Common NUMA Features
config NUMA
- bool "Numa Memory Allocation and Scheduler Support"
+ 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.
+ depends on X86_64
+ select USE_PERCPU_NUMA_NODE_ID
+ select OF_NUMA if OF
+ 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
@@ -1549,16 +1525,13 @@ config NUMA
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---
+ 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
@@ -1570,73 +1543,42 @@ config X86_64_ACPI_NUMA
prompt "ACPI NUMA detection"
depends on X86_64 && NUMA && ACPI && PCI
select ACPI_NUMA
- ---help---
+ help
Enable ACPI SRAT based node topology detection.
-# Some NUMA nodes have memory ranges that span
-# other nodes. Even though a pfn is valid and
-# between a node's start and end pfns, it may not
-# reside on that node. See memmap_init_zone()
-# for details.
-config NODES_SPAN_OTHER_NODES
- def_bool y
- depends on X86_64_ACPI_NUMA
-
-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---
+ depends on NUMA
+ help
Specify the maximum number of NUMA Nodes available on the target
system. Increases memory reserved to accommodate various tables.
-config ARCH_HAVE_MEMORY_PRESENT
- def_bool y
- depends on X86_32 && DISCONTIGMEM
-
config ARCH_FLATMEM_ENABLE
def_bool y
depends on X86_32 && !NUMA
-config ARCH_DISCONTIGMEM_ENABLE
- def_bool y
- depends on NUMA && X86_32
-
-config ARCH_DISCONTIGMEM_DEFAULT
- def_bool y
- depends on NUMA && X86_32
-
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 y
- depends on X86_64
+ def_bool X86_64 || (NUMA && X86_32)
config ARCH_SELECT_MEMORY_MODEL
def_bool y
- depends on ARCH_SPARSEMEM_ENABLE
+ depends on ARCH_SPARSEMEM_ENABLE && ARCH_FLATMEM_ENABLE
config ARCH_MEMORY_PROBE
bool "Enable sysfs memory/probe interface"
- depends on X86_64 && MEMORY_HOTPLUG
+ depends on MEMORY_HOTPLUG
help
This option enables a sysfs memory/probe interface for testing.
- See Documentation/memory-hotplug.txt for more information.
+ 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
@@ -1644,9 +1586,9 @@ config ARCH_PROC_KCORE_TEXT
depends on X86_64 && PROC_KCORE
config ILLEGAL_POINTER_VALUE
- hex
- default 0 if X86_32
- default 0xdead000000000000 if X86_64
+ hex
+ default 0 if X86_32
+ default 0xdead000000000000 if X86_64
config X86_PMEM_LEGACY_DEVICE
bool
@@ -1656,6 +1598,7 @@ config X86_PMEM_LEGACY
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
@@ -1665,18 +1608,9 @@ config X86_PMEM_LEGACY
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---
+ 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
@@ -1700,44 +1634,15 @@ config X86_BOOTPARAM_MEMORY_CORRUPTION_CHECK
bool "Set the default setting of memory_corruption_check"
depends on X86_CHECK_BIOS_CORRUPTION
default y
- ---help---
+ 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
- ---help---
+ 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
@@ -1763,7 +1668,7 @@ config MATH_EMULATION
config MTRR
def_bool y
prompt "MTRR (Memory Type Range Register) support" if EXPERT
- ---help---
+ 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
@@ -1793,13 +1698,13 @@ config MTRR
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.txt> for more information.
+ See <file:Documentation/arch/x86/mtrr.rst> for more information.
config MTRR_SANITIZER
def_bool y
prompt "MTRR cleanup support"
depends on MTRR
- ---help---
+ help
Convert MTRR layout from continuous to discrete, so X drivers can
add writeback entries.
@@ -1814,7 +1719,7 @@ config MTRR_SANITIZER_ENABLE_DEFAULT
range 0 1
default "0"
depends on MTRR_SANITIZER
- ---help---
+ help
Enable mtrr cleanup default value
config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
@@ -1822,7 +1727,7 @@ config MTRR_SANITIZER_SPARE_REG_NR_DEFAULT
range 0 7
default "1"
depends on MTRR_SANITIZER
- ---help---
+ help
mtrr cleanup spare entries default, it can be changed via
mtrr_spare_reg_nr=N on the kernel command line.
@@ -1830,7 +1735,8 @@ config X86_PAT
def_bool y
prompt "x86 PAT support" if EXPERT
depends on MTRR
- ---help---
+ select ARCH_USES_PG_ARCH_2
+ help
Use PAT attributes to setup page level cache control.
PATs are the modern equivalents of MTRRs and are much more
@@ -1841,96 +1747,177 @@ config X86_PAT
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_INTEL_UMIP
+config X86_UMIP
def_bool y
- depends on CPU_SUP_INTEL
- prompt "Intel User Mode Instruction Prevention" if EXPERT
- ---help---
- The User Mode Instruction Prevention (UMIP) is a security
- feature in newer Intel 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.
+ 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_MPX
- prompt "Intel MPX (Memory Protection Extensions)"
+config CC_HAS_IBT
+ # GCC >= 9 and binutils >= 2.29
+ # Retpoline check to work around https://gcc.gnu.org/bugzilla/show_bug.cgi?id=93654
+ def_bool ((CC_IS_GCC && $(cc-option, -fcf-protection=branch -mindirect-branch-register)) || CC_IS_CLANG) && \
+ $(as-instr,endbr64)
+
+config X86_CET
def_bool n
- # Note: only available in 64-bit mode due to VMA flags shortage
- depends on CPU_SUP_INTEL && X86_64
- select ARCH_USES_HIGH_VMA_FLAGS
- ---help---
- MPX provides hardware features that can be used in
- conjunction with compiler-instrumented code to check
- memory references. It is designed to detect buffer
- overflow or underflow bugs.
-
- This option enables running applications which are
- instrumented or otherwise use MPX. It does not use MPX
- itself inside the kernel or to protect the kernel
- against bad memory references.
-
- Enabling this option will make the kernel larger:
- ~8k of kernel text and 36 bytes of data on a 64-bit
- defconfig. It adds a long to the 'mm_struct' which
- will increase the kernel memory overhead of each
- process and adds some branches to paths used during
- exec() and munmap().
-
- For details, see Documentation/x86/intel_mpx.txt
+ help
+ CET features configured (Shadow stack or IBT)
- If unsure, say N.
+config X86_KERNEL_IBT
+ prompt "Indirect Branch Tracking"
+ def_bool y
+ depends on X86_64 && CC_HAS_IBT && HAVE_OBJTOOL
+ select OBJTOOL
+ select X86_CET
+ help
+ Build the kernel with support for Indirect Branch Tracking, a
+ hardware support course-grain forward-edge Control Flow Integrity
+ protection. It enforces that all indirect calls must land on
+ an ENDBR instruction, as such, the compiler will instrument the
+ code with them to make this happen.
+
+ In addition to building the kernel with IBT, seal all functions that
+ are not indirect call targets, avoiding them ever becoming one.
+
+ This requires LTO like objtool runs and will slow down the build. It
+ does significantly reduce the number of ENDBR instructions in the
+ kernel image.
config X86_INTEL_MEMORY_PROTECTION_KEYS
- prompt "Intel Memory Protection Keys"
+ prompt "Memory Protection Keys"
def_bool y
# Note: only available in 64-bit mode
- depends on CPU_SUP_INTEL && X86_64
+ depends on X86_64 && (CPU_SUP_INTEL || CPU_SUP_AMD)
select ARCH_USES_HIGH_VMA_FLAGS
select ARCH_HAS_PKEYS
- ---help---
+ 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/x86/protection-keys.txt
+ For details, see Documentation/core-api/protection-keys.rst
If unsure, say y.
+config ARCH_PKEY_BITS
+ int
+ default 4
+
+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 && X86_X2APIC
+ select CRYPTO_LIB_SHA256
+ select MMU_NOTIFIER
+ select NUMA_KEEP_MEMINFO if NUMA
+ select XARRAY_MULTI
+ 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 X86_USER_SHADOW_STACK
+ bool "X86 userspace shadow stack"
+ depends on AS_WRUSS
+ depends on X86_64
+ select ARCH_USES_HIGH_VMA_FLAGS
+ select ARCH_HAS_USER_SHADOW_STACK
+ select X86_CET
+ help
+ Shadow stack protection is a hardware feature that detects function
+ return address corruption. This helps mitigate ROP attacks.
+ Applications must be enabled to use it, and old userspace does not
+ get protection "for free".
+
+ CPUs supporting shadow stacks were first released in 2020.
+
+ See Documentation/arch/x86/shstk.rst for more information.
+
+ If unsure, say N.
+
+config INTEL_TDX_HOST
+ bool "Intel Trust Domain Extensions (TDX) host support"
+ depends on CPU_SUP_INTEL
+ depends on X86_64
+ depends on KVM_INTEL
+ depends on X86_X2APIC
+ select ARCH_KEEP_MEMBLOCK
+ depends on CONTIG_ALLOC
+ depends on X86_MCE
+ help
+ Intel Trust Domain Extensions (TDX) protects guest VMs from malicious
+ host and certain physical attacks. This option enables necessary TDX
+ support in the host kernel to run confidential VMs.
+
+ If unsure, say N.
+
config EFI
bool "EFI runtime service support"
depends on ACPI
select UCS2_STRING
select EFI_RUNTIME_WRAPPERS
- ---help---
+ select ARCH_USE_MEMREMAP_PROT
+ select EFI_RUNTIME_MAP if KEXEC_CORE
+ help
This enables the kernel to use EFI runtime services that are
available (such as the EFI variable services).
@@ -1942,131 +1929,110 @@ config EFI
platforms.
config EFI_STUB
- bool "EFI stub support"
- depends on EFI && !X86_USE_3DNOW
- select RELOCATABLE
- ---help---
- This kernel feature allows a bzImage to be loaded directly
+ bool "EFI stub support"
+ depends on EFI
+ select RELOCATABLE
+ help
+ This kernel feature allows a bzImage to be loaded directly
by EFI firmware without the use of a bootloader.
- See Documentation/efi-stub.txt for more information.
+ See Documentation/admin-guide/efi-stub.rst for more information.
+
+config EFI_HANDOVER_PROTOCOL
+ bool "EFI handover protocol (DEPRECATED)"
+ depends on EFI_STUB
+ default y
+ help
+ Select this in order to include support for the deprecated EFI
+ handover protocol, which defines alternative entry points into the
+ EFI stub. This is a practice that has no basis in the UEFI
+ specification, and requires a priori knowledge on the part of the
+ bootloader about Linux/x86 specific ways of passing the command line
+ and initrd, and where in memory those assets may be loaded.
+
+ If in doubt, say Y. Even though the corresponding support is not
+ present in upstream GRUB or other bootloaders, most distros build
+ GRUB with numerous downstream patches applied, and may rely on the
+ handover protocol as as result.
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.
+ 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.
+ 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.
+ If unsure, say N.
-config SECCOMP
- def_bool y
- prompt "Enable seccomp to safely compute untrusted bytecode"
- ---help---
- This kernel feature is useful for number crunching applications
- that may need to compute untrusted bytecode during their
- execution. By using pipes or other transports made available to
- the process as file descriptors supporting the read/write
- syscalls, it's possible to isolate those applications in
- their own address space using seccomp. Once seccomp is
- enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
- and the task is only allowed to execute a few safe syscalls
- defined by each seccomp mode.
+config EFI_RUNTIME_MAP
+ bool "Export EFI runtime maps to sysfs" if EXPERT
+ depends on EFI
+ help
+ Export EFI runtime memory regions to /sys/firmware/efi/runtime-map.
+ That memory map is required by the 2nd kernel to set up EFI virtual
+ mappings after kexec, but can also be used for debugging purposes.
- If unsure, say Y. Only embedded should say N here.
+ See also Documentation/ABI/testing/sysfs-firmware-efi-runtime-map.
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_VERIFY_SIG
- bool "Verify kernel signature during kexec_file_load() syscall"
+config ARCH_SUPPORTS_KEXEC
+ def_bool y
+
+config ARCH_SUPPORTS_KEXEC_FILE
+ def_bool X86_64
+
+config ARCH_SELECTS_KEXEC_FILE
+ def_bool y
depends on KEXEC_FILE
- ---help---
- This option makes kernel signature verification mandatory for
- the kexec_file_load() syscall.
-
- In addition to that option, you need to enable signature
- verification for the corresponding kernel image type being
- loaded in order for this to work.
-
-config KEXEC_BZIMAGE_VERIFY_SIG
- bool "Enable bzImage signature verification support"
- depends on KEXEC_VERIFY_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/kdump/kdump.txt
-
-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
+ select HAVE_IMA_KEXEC if IMA
+
+config ARCH_SUPPORTS_KEXEC_PURGATORY
+ def_bool y
+
+config ARCH_SUPPORTS_KEXEC_SIG
+ def_bool y
+
+config ARCH_SUPPORTS_KEXEC_SIG_FORCE
+ def_bool y
+
+config ARCH_SUPPORTS_KEXEC_BZIMAGE_VERIFY_SIG
+ def_bool y
+
+config ARCH_SUPPORTS_KEXEC_JUMP
+ def_bool y
+
+config ARCH_SUPPORTS_KEXEC_HANDOVER
+ def_bool X86_64
+
+config ARCH_SUPPORTS_CRASH_DUMP
+ def_bool X86_64 || (X86_32 && HIGHMEM)
+
+config ARCH_DEFAULT_CRASH_DUMP
+ def_bool y
+
+config ARCH_SUPPORTS_CRASH_HOTPLUG
+ def_bool y
+
+config ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION
+ def_bool CRASH_RESERVE
config PHYSICAL_START
hex "Physical address where the kernel is loaded" if (EXPERT || CRASH_DUMP)
default "0x1000000"
- ---help---
+ 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.
+ If the kernel is 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. The only exception is if it is loaded below the
+ above physical address, in which case it will relocate itself there.
In normal kdump cases one does not have to set/change this option
as now bzImage can be compiled as a completely relocatable image
@@ -2084,7 +2050,7 @@ config PHYSICAL_START
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/kdump/kdump.txt
+ 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
@@ -2100,7 +2066,7 @@ config PHYSICAL_START
config RELOCATABLE
bool "Build a relocatable kernel"
default y
- ---help---
+ 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,
@@ -2118,7 +2084,7 @@ config RANDOMIZE_BASE
bool "Randomize the address of the kernel image (KASLR)"
depends on RELOCATABLE
default y
- ---help---
+ 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
@@ -2153,13 +2119,14 @@ config RANDOMIZE_BASE
config X86_NEED_RELOCS
def_bool y
depends on RANDOMIZE_BASE || (X86_32 && RELOCATABLE)
+ select ARCH_VMLINUX_NEEDS_RELOCS
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---
+ 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.
@@ -2181,29 +2148,22 @@ config PHYSICAL_ALIGN
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.
+ 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.
+ 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.
+ If unsure, say Y.
config RANDOMIZE_MEMORY_PHYSICAL_PADDING
hex "Physical memory mapping padding" if EXPERT
@@ -2212,72 +2172,35 @@ config RANDOMIZE_MEMORY_PHYSICAL_PADDING
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.
+ 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.
+ If unsure, leave at the default value.
-config HOTPLUG_CPU
- bool "Support for hot-pluggable CPUs"
- depends on SMP
- ---help---
- Say Y here to allow turning CPUs off and on. CPUs can be
- controlled through /sys/devices/system/cpu.
- ( Note: power management support will enable this option
- automatically on SMP systems. )
- Say N if you want to disable CPU hotplug.
-
-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.
+config ADDRESS_MASKING
+ bool "Linear Address Masking support"
+ depends on X86_64
+ depends on COMPILE_TEST || !CPU_MITIGATIONS # wait for LASS
+ help
+ Linear Address Masking (LAM) modifies the checking that is applied
+ to 64-bit linear addresses, allowing software to use of the
+ untranslated address bits for metadata.
- 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.
+ The capability can be used for efficient address sanitizers (ASAN)
+ implementation and for optimizations in JITs.
- If unsure, say N.
+config HOTPLUG_CPU
+ def_bool y
+ depends on SMP
config COMPAT_VDSO
def_bool n
- prompt "Disable the 32-bit vDSO (needed for glibc 2.3.3)"
+ prompt "Workaround for glibc 2.3.2 / 2.3.3 (released in year 2003/2004)"
depends on COMPAT_32
- ---help---
+ 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.
@@ -2301,7 +2224,7 @@ config COMPAT_VDSO
choice
prompt "vsyscall table for legacy applications"
depends on X86_64
- default LEGACY_VSYSCALL_EMULATE
+ 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
@@ -2309,23 +2232,26 @@ choice
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|none].
+ line parameter vsyscall=[emulate|xonly|none]. Emulate mode
+ is deprecated and can only be enabled using the kernel command
+ line.
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".
+ If unsure, select "Emulate execution only".
- config LEGACY_VSYSCALL_EMULATE
- bool "Emulate"
+ config LEGACY_VSYSCALL_XONLY
+ bool "Emulate execution only"
help
- The kernel traps and emulates calls into the fixed
- vsyscall address mapping. This makes the mapping
- non-executable, but it still contains known contents,
- which could be used in certain rare security vulnerability
- exploits. This configuration is recommended when userspace
- still uses the vsyscall area.
+ 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"
@@ -2340,7 +2266,7 @@ endchoice
config CMDLINE_BOOL
bool "Built-in kernel command line"
- ---help---
+ 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
@@ -2358,7 +2284,7 @@ config CMDLINE
string "Built-in kernel command string"
depends on CMDLINE_BOOL
default ""
- ---help---
+ 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
@@ -2373,8 +2299,8 @@ config CMDLINE
config CMDLINE_OVERRIDE
bool "Built-in command line overrides boot loader arguments"
- depends on CMDLINE_BOOL
- ---help---
+ 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.
@@ -2384,7 +2310,7 @@ config CMDLINE_OVERRIDE
config MODIFY_LDT_SYSCALL
bool "Enable the LDT (local descriptor table)" if EXPERT
default y
- ---help---
+ 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
@@ -2397,37 +2323,403 @@ config MODIFY_LDT_SYSCALL
Saying 'N' here may make sense for embedded or server kernels.
+config STRICT_SIGALTSTACK_SIZE
+ bool "Enforce strict size checking for sigaltstack"
+ depends on DYNAMIC_SIGFRAME
+ help
+ For historical reasons MINSIGSTKSZ is a constant which became
+ already too small with AVX512 support. Add a mechanism to
+ enforce strict checking of the sigaltstack size against the
+ real size of the FPU frame. This option enables the check
+ by default. It can also be controlled via the kernel command
+ line option 'strict_sas_size' independent of this config
+ switch. Enabling it might break existing applications which
+ allocate a too small sigaltstack but 'work' because they
+ never get a signal delivered.
+
+ Say 'N' unless you want to really enforce this check.
+
+config CFI_AUTO_DEFAULT
+ bool "Attempt to use FineIBT by default at boot time"
+ depends on FINEIBT
+ depends on !RUST || RUSTC_VERSION >= 108800
+ default y
+ help
+ Attempt to use FineIBT by default at boot time. If enabled,
+ this is the same as booting with "cfi=auto". If disabled,
+ this is the same as booting with "cfi=kcfi".
+
source "kernel/livepatch/Kconfig"
+config X86_BUS_LOCK_DETECT
+ bool "Split Lock Detect and Bus Lock Detect support"
+ depends on CPU_SUP_INTEL || CPU_SUP_AMD
+ default y
+ help
+ Enable Split Lock Detect and Bus Lock Detect functionalities.
+ See <file:Documentation/arch/x86/buslock.rst> for more information.
+
endmenu
-config ARCH_HAS_ADD_PAGES
- def_bool y
- depends on X86_64 && ARCH_ENABLE_MEMORY_HOTPLUG
+config CC_HAS_NAMED_AS
+ def_bool $(success,echo 'int __seg_fs fs; int __seg_gs gs;' | $(CC) -x c - -S -o /dev/null)
+ depends on CC_IS_GCC
+
+#
+# -fsanitize=kernel-address (KASAN) and -fsanitize=thread (KCSAN)
+# are incompatible with named address spaces with GCC < 13.3
+# (see GCC PR sanitizer/111736 and also PR sanitizer/115172).
+#
-config ARCH_ENABLE_MEMORY_HOTPLUG
+config CC_HAS_NAMED_AS_FIXED_SANITIZERS
def_bool y
- depends on X86_64 || (X86_32 && HIGHMEM)
+ depends on !(KASAN || KCSAN) || GCC_VERSION >= 130300
+ depends on !(UBSAN_BOOL && KASAN) || GCC_VERSION >= 140200
-config ARCH_ENABLE_MEMORY_HOTREMOVE
+config USE_X86_SEG_SUPPORT
+ def_bool CC_HAS_NAMED_AS
+ depends on CC_HAS_NAMED_AS_FIXED_SANITIZERS
+
+config CC_HAS_SLS
+ def_bool $(cc-option,-mharden-sls=all)
+
+config CC_HAS_RETURN_THUNK
+ def_bool $(cc-option,-mfunction-return=thunk-extern)
+
+config CC_HAS_ENTRY_PADDING
+ def_bool $(cc-option,-fpatchable-function-entry=16,16)
+
+config CC_HAS_KCFI_ARITY
+ def_bool $(cc-option,-fsanitize=kcfi -fsanitize-kcfi-arity)
+ depends on CC_IS_CLANG && !RUST
+
+config FUNCTION_PADDING_CFI
+ int
+ default 59 if FUNCTION_ALIGNMENT_64B
+ default 27 if FUNCTION_ALIGNMENT_32B
+ default 11 if FUNCTION_ALIGNMENT_16B
+ default 3 if FUNCTION_ALIGNMENT_8B
+ default 0
+
+# Basically: FUNCTION_ALIGNMENT - 5*CFI
+# except Kconfig can't do arithmetic :/
+config FUNCTION_PADDING_BYTES
+ int
+ default FUNCTION_PADDING_CFI if CFI
+ default FUNCTION_ALIGNMENT
+
+config CALL_PADDING
+ def_bool n
+ depends on CC_HAS_ENTRY_PADDING && OBJTOOL
+ select FUNCTION_ALIGNMENT_16B
+
+config FINEIBT
def_bool y
- depends on MEMORY_HOTPLUG
+ depends on X86_KERNEL_IBT && CFI && MITIGATION_RETPOLINE
+ select CALL_PADDING
-config USE_PERCPU_NUMA_NODE_ID
+config FINEIBT_BHI
def_bool y
- depends on NUMA
+ depends on FINEIBT && CC_HAS_KCFI_ARITY
-config ARCH_ENABLE_SPLIT_PMD_PTLOCK
+config HAVE_CALL_THUNKS
def_bool y
- depends on X86_64 || X86_PAE
+ depends on CC_HAS_ENTRY_PADDING && MITIGATION_RETHUNK && OBJTOOL
-config ARCH_ENABLE_HUGEPAGE_MIGRATION
+config CALL_THUNKS
+ def_bool n
+ select CALL_PADDING
+
+config PREFIX_SYMBOLS
def_bool y
- depends on X86_64 && HUGETLB_PAGE && MIGRATION
+ depends on CALL_PADDING && !CFI
+
+menuconfig CPU_MITIGATIONS
+ bool "Mitigations for CPU vulnerabilities"
+ default y
+ help
+ Say Y here to enable options which enable mitigations for hardware
+ vulnerabilities (usually related to speculative execution).
+ Mitigations can be disabled or restricted to SMT systems at runtime
+ via the "mitigations" kernel parameter.
+
+ If you say N, all mitigations will be disabled. This CANNOT be
+ overridden at runtime.
+
+ Say 'Y', unless you really know what you are doing.
+
+if CPU_MITIGATIONS
+
+config MITIGATION_PAGE_TABLE_ISOLATION
+ bool "Remove the kernel mapping in user mode"
+ default y
+ depends on (X86_64 || X86_PAE)
+ help
+ This feature reduces the number of hardware side channels by
+ ensuring that the majority of kernel addresses are not mapped
+ into userspace.
+
+ See Documentation/arch/x86/pti.rst for more details.
+
+config MITIGATION_RETPOLINE
+ bool "Avoid speculative indirect branches in kernel"
+ select OBJTOOL if HAVE_OBJTOOL
+ default y
+ help
+ Compile kernel with the retpoline compiler options to guard against
+ kernel-to-user data leaks by avoiding speculative indirect
+ branches. Requires a compiler with -mindirect-branch=thunk-extern
+ support for full protection. The kernel may run slower.
+
+config MITIGATION_RETHUNK
+ bool "Enable return-thunks"
+ depends on MITIGATION_RETPOLINE && CC_HAS_RETURN_THUNK
+ select OBJTOOL if HAVE_OBJTOOL
+ default y if X86_64
+ help
+ Compile the kernel with the return-thunks compiler option to guard
+ against kernel-to-user data leaks by avoiding return speculation.
+ Requires a compiler with -mfunction-return=thunk-extern
+ support for full protection. The kernel may run slower.
+
+config MITIGATION_UNRET_ENTRY
+ bool "Enable UNRET on kernel entry"
+ depends on CPU_SUP_AMD && MITIGATION_RETHUNK && X86_64
+ default y
+ help
+ Compile the kernel with support for the retbleed=unret mitigation.
-config ARCH_ENABLE_THP_MIGRATION
+config MITIGATION_CALL_DEPTH_TRACKING
+ bool "Mitigate RSB underflow with call depth tracking"
+ depends on CPU_SUP_INTEL && HAVE_CALL_THUNKS
+ select HAVE_DYNAMIC_FTRACE_NO_PATCHABLE
+ select CALL_THUNKS
+ default y
+ help
+ Compile the kernel with call depth tracking to mitigate the Intel
+ SKL Return-Stack-Buffer (RSB) underflow issue. The mitigation is off
+ by default and needs to be enabled on the kernel command line via the
+ retbleed=stuff option. For non-affected systems the overhead of this
+ option is marginal as the call depth tracking is using run-time
+ generated call thunks in a compiler generated padding area and call
+ patching. This increases text size by ~5%. For non affected systems
+ this space is unused. On affected SKL systems this results in a
+ significant performance gain over the IBRS mitigation.
+
+config CALL_THUNKS_DEBUG
+ bool "Enable call thunks and call depth tracking debugging"
+ depends on MITIGATION_CALL_DEPTH_TRACKING
+ select FUNCTION_ALIGNMENT_32B
+ default n
+ help
+ Enable call/ret counters for imbalance detection and build in
+ a noisy dmesg about callthunks generation and call patching for
+ trouble shooting. The debug prints need to be enabled on the
+ kernel command line with 'debug-callthunks'.
+ Only enable this when you are debugging call thunks as this
+ creates a noticeable runtime overhead. If unsure say N.
+
+config MITIGATION_IBPB_ENTRY
+ bool "Enable IBPB on kernel entry"
+ depends on CPU_SUP_AMD && X86_64
+ default y
+ help
+ Compile the kernel with support for the retbleed=ibpb and
+ spec_rstack_overflow={ibpb,ibpb-vmexit} mitigations.
+
+config MITIGATION_IBRS_ENTRY
+ bool "Enable IBRS on kernel entry"
+ depends on CPU_SUP_INTEL && X86_64
+ default y
+ help
+ Compile the kernel with support for the spectre_v2=ibrs mitigation.
+ This mitigates both spectre_v2 and retbleed at great cost to
+ performance.
+
+config MITIGATION_SRSO
+ bool "Mitigate speculative RAS overflow on AMD"
+ depends on CPU_SUP_AMD && X86_64 && MITIGATION_RETHUNK
+ default y
+ help
+ Enable the SRSO mitigation needed on AMD Zen1-4 machines.
+
+config MITIGATION_SLS
+ bool "Mitigate Straight-Line-Speculation"
+ depends on CC_HAS_SLS && X86_64
+ select OBJTOOL if HAVE_OBJTOOL
+ default n
+ help
+ Compile the kernel with straight-line-speculation options to guard
+ against straight line speculation. The kernel image might be slightly
+ larger.
+
+config MITIGATION_GDS
+ bool "Mitigate Gather Data Sampling"
+ depends on CPU_SUP_INTEL
+ default y
+ help
+ Enable mitigation for Gather Data Sampling (GDS). GDS is a hardware
+ vulnerability which allows unprivileged speculative access to data
+ which was previously stored in vector registers. The attacker uses gather
+ instructions to infer the stale vector register data.
+
+config MITIGATION_RFDS
+ bool "RFDS Mitigation"
+ depends on CPU_SUP_INTEL
+ default y
+ help
+ Enable mitigation for Register File Data Sampling (RFDS) by default.
+ RFDS is a hardware vulnerability which affects Intel Atom CPUs. It
+ allows unprivileged speculative access to stale data previously
+ stored in floating point, vector and integer registers.
+ See also <file:Documentation/admin-guide/hw-vuln/reg-file-data-sampling.rst>
+
+config MITIGATION_SPECTRE_BHI
+ bool "Mitigate Spectre-BHB (Branch History Injection)"
+ depends on CPU_SUP_INTEL
+ default y
+ help
+ Enable BHI mitigations. BHI attacks are a form of Spectre V2 attacks
+ where the branch history buffer is poisoned to speculatively steer
+ indirect branches.
+ See <file:Documentation/admin-guide/hw-vuln/spectre.rst>
+
+config MITIGATION_MDS
+ bool "Mitigate Microarchitectural Data Sampling (MDS) hardware bug"
+ depends on CPU_SUP_INTEL
+ default y
+ help
+ Enable mitigation for Microarchitectural Data Sampling (MDS). MDS is
+ a hardware vulnerability which allows unprivileged speculative access
+ to data which is available in various CPU internal buffers.
+ See also <file:Documentation/admin-guide/hw-vuln/mds.rst>
+
+config MITIGATION_TAA
+ bool "Mitigate TSX Asynchronous Abort (TAA) hardware bug"
+ depends on CPU_SUP_INTEL
+ default y
+ help
+ Enable mitigation for TSX Asynchronous Abort (TAA). TAA is a hardware
+ vulnerability that allows unprivileged speculative access to data
+ which is available in various CPU internal buffers by using
+ asynchronous aborts within an Intel TSX transactional region.
+ See also <file:Documentation/admin-guide/hw-vuln/tsx_async_abort.rst>
+
+config MITIGATION_MMIO_STALE_DATA
+ bool "Mitigate MMIO Stale Data hardware bug"
+ depends on CPU_SUP_INTEL
+ default y
+ help
+ Enable mitigation for MMIO Stale Data hardware bugs. Processor MMIO
+ Stale Data Vulnerabilities are a class of memory-mapped I/O (MMIO)
+ vulnerabilities that can expose data. The vulnerabilities require the
+ attacker to have access to MMIO.
+ See also
+ <file:Documentation/admin-guide/hw-vuln/processor_mmio_stale_data.rst>
+
+config MITIGATION_L1TF
+ bool "Mitigate L1 Terminal Fault (L1TF) hardware bug"
+ depends on CPU_SUP_INTEL
+ default y
+ help
+ Mitigate L1 Terminal Fault (L1TF) hardware bug. L1 Terminal Fault is a
+ hardware vulnerability which allows unprivileged speculative access to data
+ available in the Level 1 Data Cache.
+ See <file:Documentation/admin-guide/hw-vuln/l1tf.rst
+
+config MITIGATION_RETBLEED
+ bool "Mitigate RETBleed hardware bug"
+ depends on (CPU_SUP_INTEL && MITIGATION_SPECTRE_V2) || MITIGATION_UNRET_ENTRY || MITIGATION_IBPB_ENTRY
+ default y
+ help
+ Enable mitigation for RETBleed (Arbitrary Speculative Code Execution
+ with Return Instructions) vulnerability. RETBleed is a speculative
+ execution attack which takes advantage of microarchitectural behavior
+ in many modern microprocessors, similar to Spectre v2. An
+ unprivileged attacker can use these flaws to bypass conventional
+ memory security restrictions to gain read access to privileged memory
+ that would otherwise be inaccessible.
+
+config MITIGATION_SPECTRE_V1
+ bool "Mitigate SPECTRE V1 hardware bug"
+ default y
+ help
+ Enable mitigation for Spectre V1 (Bounds Check Bypass). Spectre V1 is a
+ class of side channel attacks that takes advantage of speculative
+ execution that bypasses conditional branch instructions used for
+ memory access bounds check.
+ See also <file:Documentation/admin-guide/hw-vuln/spectre.rst>
+
+config MITIGATION_SPECTRE_V2
+ bool "Mitigate SPECTRE V2 hardware bug"
+ default y
+ help
+ Enable mitigation for Spectre V2 (Branch Target Injection). Spectre
+ V2 is a class of side channel attacks that takes advantage of
+ indirect branch predictors inside the processor. In Spectre variant 2
+ attacks, the attacker can steer speculative indirect branches in the
+ victim to gadget code by poisoning the branch target buffer of a CPU
+ used for predicting indirect branch addresses.
+ See also <file:Documentation/admin-guide/hw-vuln/spectre.rst>
+
+config MITIGATION_SRBDS
+ bool "Mitigate Special Register Buffer Data Sampling (SRBDS) hardware bug"
+ depends on CPU_SUP_INTEL
+ default y
+ help
+ Enable mitigation for Special Register Buffer Data Sampling (SRBDS).
+ SRBDS is a hardware vulnerability that allows Microarchitectural Data
+ Sampling (MDS) techniques to infer values returned from special
+ register accesses. An unprivileged user can extract values returned
+ from RDRAND and RDSEED executed on another core or sibling thread
+ using MDS techniques.
+ See also
+ <file:Documentation/admin-guide/hw-vuln/special-register-buffer-data-sampling.rst>
+
+config MITIGATION_SSB
+ bool "Mitigate Speculative Store Bypass (SSB) hardware bug"
+ default y
+ help
+ Enable mitigation for Speculative Store Bypass (SSB). SSB is a
+ hardware security vulnerability and its exploitation takes advantage
+ of speculative execution in a similar way to the Meltdown and Spectre
+ security vulnerabilities.
+
+config MITIGATION_ITS
+ bool "Enable Indirect Target Selection mitigation"
+ depends on CPU_SUP_INTEL && X86_64
+ depends on MITIGATION_RETPOLINE && MITIGATION_RETHUNK
+ select EXECMEM
+ default y
+ help
+ Enable Indirect Target Selection (ITS) mitigation. ITS is a bug in
+ BPU on some Intel CPUs that may allow Spectre V2 style attacks. If
+ disabled, mitigation cannot be enabled via cmdline.
+ See <file:Documentation/admin-guide/hw-vuln/indirect-target-selection.rst>
+
+config MITIGATION_TSA
+ bool "Mitigate Transient Scheduler Attacks"
+ depends on CPU_SUP_AMD
+ default y
+ help
+ Enable mitigation for Transient Scheduler Attacks. TSA is a hardware
+ security vulnerability on AMD CPUs which can lead to forwarding of
+ invalid info to subsequent instructions and thus can affect their
+ timing and thereby cause a leakage.
+
+config MITIGATION_VMSCAPE
+ bool "Mitigate VMSCAPE"
+ depends on KVM
+ default y
+ help
+ Enable mitigation for VMSCAPE attacks. VMSCAPE is a hardware security
+ vulnerability on Intel and AMD CPUs that may allow a guest to do
+ Spectre v2 style attacks on userspace hypervisor.
+endif
+
+config ARCH_HAS_ADD_PAGES
def_bool y
- depends on X86_64 && TRANSPARENT_HUGEPAGE
+ depends on ARCH_ENABLE_MEMORY_HOTPLUG
menu "Power management and ACPI options"
@@ -2439,8 +2731,6 @@ source "kernel/power/Kconfig"
source "drivers/acpi/Kconfig"
-source "drivers/sfi/Kconfig"
-
config X86_APM_BOOT
def_bool y
depends on APM
@@ -2448,7 +2738,7 @@ config X86_APM_BOOT
menuconfig APM
tristate "APM (Advanced Power Management) BIOS support"
depends on X86_32 && PM_SLEEP
- ---help---
+ 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
@@ -2463,7 +2753,7 @@ menuconfig APM
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.txt>
+ 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>.
@@ -2487,7 +2777,7 @@ menuconfig APM
1) make sure that you have enough swap space and that it is
enabled.
- 2) pass the "no-hlt" option to the kernel
+ 2) pass the "idle=poll" 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
@@ -2508,14 +2798,14 @@ if APM
config APM_IGNORE_USER_SUSPEND
bool "Ignore USER SUSPEND"
- ---help---
+ 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---
+ 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
@@ -2533,7 +2823,7 @@ config APM_DO_ENABLE
config APM_CPU_IDLE
depends on CPU_IDLE
bool "Make CPU Idle calls when idle"
- ---help---
+ 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
@@ -2544,7 +2834,7 @@ config APM_CPU_IDLE
config APM_DISPLAY_BLANK
bool "Enable console blanking using APM"
- ---help---
+ 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
@@ -2557,7 +2847,7 @@ config APM_DISPLAY_BLANK
config APM_ALLOW_INTS
bool "Allow interrupts during APM BIOS calls"
- ---help---
+ 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
@@ -2575,14 +2865,13 @@ source "drivers/idle/Kconfig"
endmenu
-
menu "Bus options (PCI etc.)"
choice
prompt "PCI access mode"
depends on X86_32 && PCI
default PCI_GOANY
- ---help---
+ 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
@@ -2627,8 +2916,21 @@ config PCI_DIRECT
config PCI_MMCONFIG
bool "Support mmconfig PCI config space access" if X86_64
default y
- depends on PCI && (ACPI || SFI || JAILHOUSE_GUEST)
+ depends on PCI && (ACPI || JAILHOUSE_GUEST)
depends on X86_64 || (PCI_GOANY || PCI_GOMMCONFIG)
+ help
+ Add support for accessing the PCI configuration space as a memory
+ mapped area. It is the recommended method if the system supports
+ this (it must have PCI Express and ACPI for it to be available).
+
+ In the unlikely case that enabling this configuration option causes
+ problems, the mechanism can be switched off with the 'pci=nommconf'
+ command line parameter.
+
+ Say N only if you are sure that your platform does not support this
+ access method or you have problems caused by it.
+
+ Say Y otherwise.
config PCI_OLPC
def_bool y
@@ -2637,20 +2939,27 @@ config PCI_OLPC
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
+ bool "Read PCI host bridge windows from the CNB20LE chipset" if EXPERT
+ depends on X86_32 && 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.
+ The ServerWorks (later Broadcom) CNB20LE was a chipset designed
+ most probably only for Pentium III.
+
+ To find out if you have such a chipset, search for a PCI device with
+ 1166:0009 PCI IDs, for example by executing
+ lspci -nn | grep '1166:0009'
+ The code is inactive if there is none.
+
There's no public spec for this chipset, and this functionality
is known to be incomplete.
@@ -2679,7 +2988,7 @@ if X86_32
config ISA
bool "ISA support"
- ---help---
+ 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
@@ -2688,7 +2997,7 @@ config ISA
config SCx200
tristate "NatSemi SCx200 support"
- ---help---
+ 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
@@ -2700,7 +3009,7 @@ config SCx200HR_TIMER
tristate "NatSemi SCx200 27MHz High-Resolution Timer Support"
depends on SCx200
default y
- ---help---
+ 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
@@ -2714,20 +3023,21 @@ config OLPC
select OF
select OF_PROMTREE
select IRQ_DOMAIN
- ---help---
+ 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---
+ 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---
+ help
Add support for the XO-1 real time clock, which can be used as a
programmable wakeup source.
@@ -2736,7 +3046,7 @@ config OLPC_XO1_SCI
depends on OLPC && OLPC_XO1_PM && GPIO_CS5535=y
depends on INPUT=y
select POWER_SUPPLY
- ---help---
+ help
Add support for SCI-based features of the OLPC XO-1 laptop:
- EC-driven system wakeups
- Power button
@@ -2749,16 +3059,20 @@ config OLPC_XO15_SCI
bool "OLPC XO-1.5 SCI extras"
depends on OLPC && ACPI
select POWER_SUPPLY
- ---help---
+ 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 GEODE_COMMON
+ bool
+
config ALIX
bool "PCEngines ALIX System Support (LED setup)"
select GPIOLIB
- ---help---
+ select GEODE_COMMON
+ 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
@@ -2772,14 +3086,16 @@ config ALIX
config NET5501
bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
select GPIOLIB
- ---help---
+ select GEODE_COMMON
+ help
This option enables system support for the Soekris Engineering net5501.
config GEOS
bool "Traverse Technologies GEOS System Support (LEDS, GPIO, etc)"
select GPIOLIB
+ select GEODE_COMMON
depends on DMI
- ---help---
+ help
This option enables system support for the Traverse Technologies GEOS.
config TS5500
@@ -2788,44 +3104,21 @@ config TS5500
select CHECK_SIGNATURE
select NEW_LEDS
select LEDS_CLASS
- ---help---
+ 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
+ depends on AMD_NODE
-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.
+config AMD_NODE
+ def_bool y
+ depends on CPU_SUP_AMD && PCI
endmenu
-
menu "Binary Emulations"
config IA32_EMULATION
@@ -2833,32 +3126,35 @@ config IA32_EMULATION
depends on X86_64
select ARCH_WANT_OLD_COMPAT_IPC
select BINFMT_ELF
- select COMPAT_BINFMT_ELF
select COMPAT_OLD_SIGACTION
- ---help---
+ 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"
+config IA32_EMULATION_DEFAULT_DISABLED
+ bool "IA32 emulation disabled by default"
+ default n
depends on IA32_EMULATION
- ---help---
- Support old a.out binaries in the 32bit emulation.
+ help
+ Make IA32 emulation disabled by default. This prevents loading 32-bit
+ processes and access to 32-bit syscalls. If unsure, leave it to its
+ default value.
-config X86_X32
+config X86_X32_ABI
bool "x32 ABI for 64-bit mode"
depends on X86_64
- ---help---
+ # llvm-objcopy does not convert x86_64 .note.gnu.property or
+ # compressed debug sections to x86_x32 properly:
+ # https://github.com/ClangBuiltLinux/linux/issues/514
+ # https://github.com/ClangBuiltLinux/linux/issues/1141
+ depends on $(success,$(OBJCOPY) --version | head -n1 | grep -qv llvm)
+ 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
@@ -2867,35 +3163,20 @@ config COMPAT_32
config COMPAT
def_bool y
- depends on IA32_EMULATION || X86_X32
+ depends on IA32_EMULATION || X86_X32_ABI
-if COMPAT
config COMPAT_FOR_U64_ALIGNMENT
def_bool y
-
-config SYSVIPC_COMPAT
- def_bool y
- depends on SYSVIPC
-endif
+ depends on COMPAT
endmenu
-
config HAVE_ATOMIC_IOMAP
def_bool y
depends on X86_32
-config X86_DEV_DMA_OPS
- bool
- depends on X86_64 || STA2X11
-
-config X86_DMA_REMAP
- bool
- depends on STA2X11
-
-config HAVE_GENERIC_GUP
- def_bool y
+source "arch/x86/kvm/Kconfig"
-source "drivers/firmware/Kconfig"
+source "arch/x86/Kconfig.cpufeatures"
-source "arch/x86/kvm/Kconfig"
+source "arch/x86/Kconfig.assembler"