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-rw-r--r--arch/x86/Kconfig1212
1 files changed, 723 insertions, 489 deletions
diff --git a/arch/x86/Kconfig b/arch/x86/Kconfig
index 67745ceab0db..80527299f859 100644
--- a/arch/x86/Kconfig
+++ b/arch/x86/Kconfig
@@ -14,7 +14,6 @@ config X86_32
select ARCH_WANT_IPC_PARSE_VERSION
select CLKSRC_I8253
select CLONE_BACKWARDS
- select GENERIC_VDSO_32
select HAVE_DEBUG_STACKOVERFLOW
select KMAP_LOCAL
select MODULES_USE_ELF_REL
@@ -26,14 +25,18 @@ config X86_64
depends on 64BIT
# Options that are inherently 64-bit kernel only:
select ARCH_HAS_GIGANTIC_PAGE
+ select ARCH_SUPPORTS_MSEAL_SYSTEM_MAPPINGS
select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
- select ARCH_USE_CMPXCHG_LOCKREF
+ 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 ARCH_HAS_ELFCORE_COMPAT
select ZONE_DMA32
+ select EXECMEM if DYNAMIC_FTRACE
+ select ACPI_MRRM if ACPI
config FORCE_DYNAMIC_FTRACE
def_bool y
@@ -59,8 +62,10 @@ config X86
#
select ACPI_LEGACY_TABLES_LOOKUP if ACPI
select ACPI_SYSTEM_POWER_STATES_SUPPORT if ACPI
+ select ACPI_HOTPLUG_CPU if ACPI_PROCESSOR && HOTPLUG_CPU
select ARCH_32BIT_OFF_T if X86_32
select ARCH_CLOCKSOURCE_INIT
+ 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
@@ -68,23 +73,33 @@ config X86
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_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_PTE_DEVMAP if X86_64
+ select ARCH_HAS_PREEMPT_LAZY
+ select ARCH_HAS_PTDUMP
select ARCH_HAS_PTE_SPECIAL
+ 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_COPY_MC if X86_64
@@ -94,10 +109,12 @@ config X86
select ARCH_HAS_STRICT_MODULE_RWX
select ARCH_HAS_SYNC_CORE_BEFORE_USERMODE
select ARCH_HAS_SYSCALL_WRAPPER
- select ARCH_HAS_UBSAN_SANITIZE_ALL
+ 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
@@ -105,14 +122,19 @@ config X86
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_CLANG if X86_64
- select ARCH_USES_CFI_TRAPS if X86_64 && CFI_CLANG
+ 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
@@ -122,14 +144,16 @@ config X86
select ARCH_WANTS_DYNAMIC_TASK_STRUCT
select ARCH_WANTS_NO_INSTR
select ARCH_WANT_GENERAL_HUGETLB
- select ARCH_WANT_HUGE_PMD_SHARE
- select ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP if X86_64
+ 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 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
# Word-size accesses may read uninitialized data past the trailing \0
# in strings and cause false KMSAN reports.
@@ -138,9 +162,11 @@ config X86
select EDAC_ATOMIC_SCRUB
select EDAC_SUPPORT
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_ENTRY
@@ -152,17 +178,17 @@ config X86
select GENERIC_IRQ_RESERVATION_MODE
select GENERIC_IRQ_SHOW
select GENERIC_PENDING_IRQ if SMP
- select GENERIC_PTDUMP
select GENERIC_SMP_IDLE_THREAD
select GENERIC_TIME_VSYSCALL
select GENERIC_GETTIMEOFDAY
- select GENERIC_VDSO_TIME_NS
- select GUP_GET_PTE_LOW_HIGH if X86_PAE
+ 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
@@ -173,13 +199,13 @@ config X86
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
@@ -195,22 +221,27 @@ config X86
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_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_FAST_GUP
+ select HAVE_GENERIC_TIF_BITS
+ select HAVE_GUP_FAST
select HAVE_FENTRY if X86_64 || DYNAMIC_FTRACE
- select HAVE_FTRACE_MCOUNT_RECORD
+ 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
@@ -231,7 +262,7 @@ config X86
select HAVE_FUNCTION_ERROR_INJECTION
select HAVE_KRETPROBES
select HAVE_RETHOOK
- select HAVE_KVM
+ select HAVE_KLP_BUILD if X86_64
select HAVE_LIVEPATCH if X86_64
select HAVE_MIXED_BREAKPOINTS_REGS
select HAVE_MOD_ARCH_SPECIFIC
@@ -242,6 +273,7 @@ config X86
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
@@ -249,7 +281,8 @@ config X86
select HAVE_PCI
select HAVE_PERF_REGS
select HAVE_PERF_USER_STACK_DUMP
- select MMU_GATHER_RCU_TABLE_FREE if PARAVIRT
+ 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
@@ -257,7 +290,7 @@ config X86
select HAVE_FUNCTION_ARG_ACCESS_API
select HAVE_SETUP_PER_CPU_AREA
select HAVE_SOFTIRQ_ON_OWN_STACK
- select HAVE_STACKPROTECTOR if CC_HAS_SANE_STACKPROTECTOR
+ select HAVE_STACKPROTECTOR
select HAVE_STACK_VALIDATION if HAVE_OBJTOOL
select HAVE_STATIC_CALL
select HAVE_STATIC_CALL_INLINE if HAVE_OBJTOOL
@@ -267,31 +300,42 @@ config X86
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 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 HAVE_ARCH_KCSAN if X86_64
- select X86_FEATURE_NAMES if PROC_FS
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
@@ -339,7 +383,7 @@ config GENERIC_CSUM
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
@@ -357,11 +401,6 @@ config ARCH_HAS_CPU_RELAX
config ARCH_HIBERNATION_POSSIBLE
def_bool y
-config ARCH_NR_GPIO
- int
- default 1024 if X86_64
- default 512
-
config ARCH_SUSPEND_POSSIBLE
def_bool y
@@ -377,14 +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 ARCH_SUPPORTS_UPROBES
def_bool y
@@ -396,20 +427,10 @@ 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) $(CLANG_FLAGS)) if 64BIT
- default $(success,$(srctree)/scripts/gcc-x86_32-has-stack-protector.sh $(CC) $(CLANG_FLAGS))
- help
- We have to make sure stack protector is unconditionally disabled if
- the compiler produces broken code or if it does not let us control
- the segment on 32-bit kernels.
-
menu "Processor type and features"
config SMP
@@ -434,36 +455,57 @@ 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.rst>,
+ 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.
+ 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)
+config AMD_SECURE_AVIC
+ bool "AMD Secure AVIC"
+ depends on AMD_MEM_ENCRYPT && X86_X2APIC
help
- This enables x2apic support on CPUs that have this feature.
+ 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.
- Some Intel systems circa 2022 and later are locked into x2APIC mode
- and can not fall back to the legacy APIC modes if SGX or TDX are
- enabled in the BIOS. They will be unable to boot without enabling
- this option.
+ 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.
@@ -475,15 +517,13 @@ config X86_MPPARSE
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 X86_CPU_RESCTRL
bool "x86 CPU resource control support"
depends on X86 && (CPU_SUP_INTEL || CPU_SUP_AMD)
- select KERNFS
- select PROC_CPU_RESCTRL if PROC_FS
+ depends on MISC_FILESYSTEMS
+ select ARCH_HAS_CPU_RESCTRL
+ select RESCTRL_FS
+ select RESCTRL_FS_PSEUDO_LOCK
help
Enable x86 CPU resource control support.
@@ -500,12 +540,14 @@ config X86_CPU_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
+config X86_FRED
+ bool "Flexible Return and Event Delivery"
+ depends on X86_64
help
- This option is needed for the systems that have more than 8 CPUs.
+ 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"
@@ -516,36 +558,25 @@ config X86_EXTENDED_PLATFORM
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 # X86_32
+ 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 # X86_64
+
# 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
@@ -586,8 +617,31 @@ config X86_UV
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)"
@@ -597,6 +651,9 @@ config X86_GOLDFISH
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"
depends on PCI
@@ -612,24 +669,6 @@ config X86_INTEL_CE
This option compiles in support for the CE4100 SOC for settop
boxes and media devices.
-config X86_INTEL_MID
- bool "Intel MID platform support"
- depends on X86_EXTENDED_PLATFORM
- depends on X86_PLATFORM_DEVICES
- depends on PCI
- depends on X86_64 || (PCI_GOANY && X86_32)
- depends on X86_IO_APIC
- select I2C
- select DW_APB_TIMER
- select INTEL_SCU_PCI
- 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
@@ -647,6 +686,17 @@ config X86_INTEL_QUARK
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
@@ -700,29 +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():
@@ -732,19 +759,6 @@ 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 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
@@ -793,6 +807,7 @@ config PARAVIRT
config PARAVIRT_XXL
bool
+ depends on X86_64
config PARAVIRT_DEBUG
bool "paravirt-ops debugging"
@@ -879,13 +894,25 @@ config ACRN_GUEST
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.
@@ -935,7 +962,6 @@ config DMI
config GART_IOMMU
bool "Old AMD GART IOMMU support"
- select DMA_OPS
select IOMMU_HELPER
select SWIOTLB
depends on X86_64 && PCI && AMD_NB
@@ -993,8 +1019,7 @@ 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
@@ -1007,7 +1032,6 @@ config NR_CPUS_RANGE_END
config NR_CPUS_DEFAULT
int
depends on X86_32
- default 32 if X86_BIGSMP
default 8 if SMP
default 1 if !SMP
@@ -1031,33 +1055,11 @@ config NR_CPUS
This is purely to save memory: each supported CPU adds about 8KB
to the kernel image.
-config SCHED_CLUSTER
- bool "Cluster scheduler support"
- depends on SMP
- default y
- help
- Cluster scheduler support improves the CPU scheduler's decision
- making when dealing with machines that have clusters of CPUs.
- Cluster usually means a couple of CPUs which are placed closely
- by sharing mid-level caches, last-level cache tags or internal
- busses.
-
-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
@@ -1082,7 +1084,7 @@ config UP_LATE_INIT
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
+ 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
@@ -1107,9 +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
@@ -1167,7 +1175,7 @@ config X86_MCE_INTEL
config X86_MCE_AMD
def_bool y
prompt "AMD MCE features"
- depends on X86_MCE && X86_LOCAL_APIC && AMD_NB
+ depends on X86_MCE && X86_LOCAL_APIC
help
Additional support for AMD specific MCE features such as
the DRAM Error Threshold.
@@ -1313,55 +1321,57 @@ 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
- help
- If you say Y here, you will be able to update the microcode on
- Intel and AMD processors. The Intel support is for the IA32 family,
- e.g. Pentium Pro, Pentium II, Pentium III, Pentium 4, Xeon etc. The
- AMD support is for families 0x10 and later. You will obviously need
- the actual microcode binary data itself which is not shipped with
- the Linux kernel.
-
- The preferred method to load microcode from a detached initrd is described
- in Documentation/x86/microcode.rst. For that you need to enable
- CONFIG_BLK_DEV_INITRD in order for the loader to be able to scan the
- initrd for microcode blobs.
-
- In addition, you can build the microcode into the kernel. For that you
- need to add the vendor-supplied microcode to the CONFIG_EXTRA_FIRMWARE
- config option.
+ select CRYPTO_LIB_SHA256 if CPU_SUP_AMD
-config MICROCODE_INTEL
- bool "Intel microcode loading support"
- depends on CPU_SUP_INTEL && MICROCODE
- default MICROCODE
- help
- This options enables microcode patch loading support for Intel
- processors.
-
- For the current Intel microcode data package go to
- <https://downloadcenter.intel.com> and search for
- 'Linux Processor Microcode Data File'.
-
-config MICROCODE_AMD
- bool "AMD microcode loading support"
- depends on CPU_SUP_AMD && MICROCODE
- help
- If you select this option, microcode patch loading support for AMD
- processors will be enabled.
+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
+ 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 too.
+ 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"
@@ -1380,15 +1390,11 @@ config X86_CPUID
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.
+ 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
@@ -1404,38 +1410,9 @@ 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.)
-
- If unsure, say "off".
+ answer "Y" here.
-config HIGHMEM4G
- bool "4GB"
- help
- Select this if you have a 32-bit processor and between 1 and 4
- gigabytes of physical RAM.
-
-config HIGHMEM64G
- bool "64GB"
- depends on !M486SX && !M486 && !M586 && !M586TSC && !M586MMX && !MGEODE_LX && !MGEODEGX1 && !MCYRIXIII && !MELAN && !MWINCHIPC6 && !MWINCHIP3D && !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
@@ -1481,41 +1458,18 @@ 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
PAE is required for NX support, and furthermore enables
larger swapspace support for non-overcommit purposes. It
has the cost of more pagetable lookup overhead, and also
consumes more pagetable space per process.
-config X86_5LEVEL
- bool "Enable 5-level page tables support"
- default y
- select DYNAMIC_MEMORY_LAYOUT
- select SPARSEMEM_VMEMMAP
- depends on X86_64
- help
- 5-level paging enables access to larger address space:
- upto 128 PiB of virtual address space and 4 PiB of
- physical address space.
-
- It will be supported by future Intel CPUs.
-
- A kernel with the option enabled can be booted on machines that
- support 4- or 5-level paging.
-
- See Documentation/x86/x86_64/5level-paging.rst for more
- information.
-
- Say N if unsure.
-
config X86_DIRECT_GBPAGES
def_bool y
depends on X86_64
@@ -1541,36 +1495,26 @@ config X86_MEM_ENCRYPT
config AMD_MEM_ENCRYPT
bool "AMD Secure Memory Encryption (SME) support"
depends on X86_64 && CPU_SUP_AMD
+ 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"
- depends on AMD_MEM_ENCRYPT
- help
- Say yes to have system memory encrypted by default if running on
- an AMD processor that supports Secure Memory Encryption (SME).
-
- If set to Y, then the encryption of system memory can be
- deactivated with the mem_encrypt=off command line option.
-
- If set to N, then the encryption of system memory can be
- activated with the mem_encrypt=on command line option.
-
# Common NUMA Features
config NUMA
bool "NUMA Memory Allocation and Scheduler Support"
depends on SMP
- depends on X86_64 || (X86_32 && HIGHMEM64G && X86_BIGSMP)
- default y if X86_BIGSMP
+ depends on X86_64
select USE_PERCPU_NUMA_NODE_ID
+ select OF_NUMA if OF
help
Enable NUMA (Non-Uniform Memory Access) support.
@@ -1581,9 +1525,6 @@ 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
@@ -1605,14 +1546,6 @@ config X86_64_ACPI_NUMA
help
Enable ACPI SRAT based node topology detection.
-config NUMA_EMU
- bool "NUMA emulation"
- depends on NUMA
- help
- Enable NUMA emulation. A flat machine will be split
- into virtual nodes when booted with "numa=fake=N", where N is the
- number of nodes. This is only useful for debugging.
-
config NODES_SHIFT
int "Maximum NUMA Nodes (as a power of 2)" if !MAXSMP
range 1 10
@@ -1630,7 +1563,6 @@ config ARCH_FLATMEM_ENABLE
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
@@ -1676,15 +1608,6 @@ 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
@@ -1775,7 +1698,7 @@ 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.rst> for more information.
+ See <file:Documentation/arch/x86/mtrr.rst> for more information.
config MTRR_SANITIZER
def_bool y
@@ -1812,6 +1735,7 @@ config X86_PAT
def_bool y
prompt "x86 PAT support" if EXPERT
depends on MTRR
+ select ARCH_USES_PG_ARCH_2
help
Use PAT attributes to setup page level cache control.
@@ -1823,10 +1747,6 @@ config X86_PAT
If unsure, say Y.
-config ARCH_USES_PG_UNCACHED
- def_bool y
- depends on X86_PAT
-
config X86_UMIP
def_bool y
prompt "User Mode Instruction Prevention" if EXPERT
@@ -1845,20 +1765,20 @@ config X86_UMIP
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
- # Clang/LLVM >= 14
- # https://github.com/llvm/llvm-project/commit/e0b89df2e0f0130881bf6c39bf31d7f6aac00e0f
- # https://github.com/llvm/llvm-project/commit/dfcf69770bc522b9e411c66454934a37c1f35332
- def_bool ((CC_IS_GCC && $(cc-option, -fcf-protection=branch -mindirect-branch-register)) || \
- (CC_IS_CLANG && CLANG_VERSION >= 140000)) && \
+ 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
+ help
+ CET features configured (Shadow stack or IBT)
+
config X86_KERNEL_IBT
prompt "Indirect Branch Tracking"
- bool
+ def_bool y
depends on X86_64 && CC_HAS_IBT && HAVE_OBJTOOL
- # https://github.com/llvm/llvm-project/commit/9d7001eba9c4cb311e03cd8cdc231f9e579f2d0f
- depends on !LD_IS_LLD || LLD_VERSION >= 140000
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
@@ -1889,6 +1809,10 @@ config X86_INTEL_MEMORY_PROTECTION_KEYS
If unsure, say y.
+config ARCH_PKEY_BITS
+ int
+ default 4
+
choice
prompt "TSX enable mode"
depends on CPU_SUP_INTEL
@@ -1937,9 +1861,7 @@ endchoice
config X86_SGX
bool "Software Guard eXtensions (SGX)"
depends on X86_64 && CPU_SUP_INTEL && X86_X2APIC
- depends on CRYPTO=y
- depends on CRYPTO_SHA256=y
- select SRCU
+ select CRYPTO_LIB_SHA256
select MMU_NOTIFIER
select NUMA_KEEP_MEMINFO if NUMA
select XARRAY_MULTI
@@ -1953,12 +1875,48 @@ config X86_SGX
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
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).
@@ -1980,6 +1938,23 @@ config EFI_STUB
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
@@ -1994,90 +1969,58 @@ config EFI_MIXED
If unsure, say N.
-source "kernel/Kconfig.hz"
-
-config KEXEC
- bool "kexec system call"
- select KEXEC_CORE
+config EFI_RUNTIME_MAP
+ bool "Export EFI runtime maps to sysfs" if EXPERT
+ depends on EFI
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.
+ 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.
- The name comes from the similarity to the exec system call.
+ See also Documentation/ABI/testing/sysfs-firmware-efi-runtime-map.
- 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.
+source "kernel/Kconfig.hz"
-config KEXEC_FILE
- bool "kexec file based system call"
- select KEXEC_CORE
- select HAVE_IMA_KEXEC if IMA
- 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_SUPPORTS_KEXEC
+ def_bool y
-config ARCH_HAS_KEXEC_PURGATORY
- def_bool KEXEC_FILE
+config ARCH_SUPPORTS_KEXEC_FILE
+ def_bool X86_64
-config KEXEC_SIG
- bool "Verify kernel signature during kexec_file_load() syscall"
+config ARCH_SELECTS_KEXEC_FILE
+ def_bool y
depends on KEXEC_FILE
- help
+ select HAVE_IMA_KEXEC if IMA
- This option makes the kexec_file_load() syscall check for a valid
- signature of the kernel image. The image can still be loaded without
- a valid signature unless you also enable KEXEC_SIG_FORCE, though if
- there's a signature that we can check, then it must be valid.
+config ARCH_SUPPORTS_KEXEC_PURGATORY
+ def_bool y
- In addition to this option, you need to enable signature
- verification for the corresponding kernel image type being
- loaded in order for this to work.
+config ARCH_SUPPORTS_KEXEC_SIG
+ def_bool y
-config KEXEC_SIG_FORCE
- bool "Require a valid signature in kexec_file_load() syscall"
- depends on KEXEC_SIG
- help
- This option makes kernel signature verification mandatory for
- the kexec_file_load() syscall.
+config ARCH_SUPPORTS_KEXEC_SIG_FORCE
+ def_bool y
-config KEXEC_BZIMAGE_VERIFY_SIG
- bool "Enable bzImage signature verification support"
- depends on KEXEC_SIG
- depends on SIGNED_PE_FILE_VERIFICATION
- select SYSTEM_TRUSTED_KEYRING
- help
- Enable bzImage signature verification support.
+config ARCH_SUPPORTS_KEXEC_BZIMAGE_VERIFY_SIG
+ def_bool y
-config CRASH_DUMP
- bool "kernel crash dumps"
- depends on X86_64 || (X86_32 && HIGHMEM)
- help
- Generate crash dump after being started by kexec.
- This should be normally only set in special crash dump kernels
- which are loaded in the main kernel with kexec-tools into
- a specially reserved region and then later executed after
- a crash by kdump/kexec. The crash dump kernel must be compiled
- to a memory address not used by the main kernel or BIOS using
- PHYSICAL_START, or it must be built as a relocatable image
- (CONFIG_RELOCATABLE=y).
- For more details see Documentation/admin-guide/kdump/kdump.rst
+config ARCH_SUPPORTS_KEXEC_JUMP
+ def_bool y
-config KEXEC_JUMP
- bool "kexec jump"
- depends on KEXEC && HIBERNATION
- help
- Jump between original kernel and kexeced kernel and invoke
- code in physical address mode via KEXEC
+config 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)
@@ -2085,11 +2028,11 @@ config PHYSICAL_START
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
@@ -2176,6 +2119,7 @@ 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"
@@ -2204,17 +2148,10 @@ 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
@@ -2243,56 +2180,25 @@ config RANDOMIZE_MEMORY_PHYSICAL_PADDING
If unsure, leave at the default value.
-config HOTPLUG_CPU
- def_bool y
- depends on SMP
-
-config BOOTPARAM_HOTPLUG_CPU0
- bool "Set default setting of cpu0_hotpluggable"
- depends on HOTPLUG_CPU
- help
- Set whether default state of cpu0_hotpluggable is on or off.
-
- Say Y here to enable CPU0 hotplug by default. If this switch
- is turned on, there is no need to give cpu0_hotplug kernel
- parameter and the CPU0 hotplug feature is enabled by default.
-
- Please note: there are two known CPU0 dependencies if you want
- to enable the CPU0 hotplug feature either by this switch or by
- cpu0_hotplug kernel parameter.
-
- First, resume from hibernate or suspend always starts from CPU0.
- So hibernate and suspend are prevented if CPU0 is offline.
-
- Second dependency is PIC interrupts always go to CPU0. CPU0 can not
- offline if any interrupt can not migrate out of CPU0. There may
- be other CPU0 dependencies.
-
- Please make sure the dependencies are under your control before
- you enable this feature.
-
- Say N if you don't want to enable CPU0 hotplug feature by default.
- You still can enable the CPU0 hotplug feature at boot by kernel
- parameter cpu0_hotplug.
-
-config DEBUG_HOTPLUG_CPU0
- def_bool n
- prompt "Debug CPU0 hotplug"
- depends on HOTPLUG_CPU
+config ADDRESS_MASKING
+ bool "Linear Address Masking support"
+ depends on X86_64
+ depends on COMPILE_TEST || !CPU_MITIGATIONS # wait for LASS
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.
+ 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
Certain buggy versions of glibc will crash if they are
@@ -2433,29 +2339,118 @@ config STRICT_SIGALTSTACK_SIZE
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 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 CC_HAS_NAMED_AS_FIXED_SANITIZERS
+ def_bool y
+ depends on !(KASAN || KCSAN) || GCC_VERSION >= 130300
+ depends on !(UBSAN_BOOL && KASAN) || GCC_VERSION >= 140200
+
+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)
-menuconfig SPECULATION_MITIGATIONS
- bool "Mitigations for speculative execution vulnerabilities"
+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 X86_KERNEL_IBT && CFI && MITIGATION_RETPOLINE
+ select CALL_PADDING
+
+config FINEIBT_BHI
+ def_bool y
+ depends on FINEIBT && CC_HAS_KCFI_ARITY
+
+config HAVE_CALL_THUNKS
+ def_bool y
+ depends on CC_HAS_ENTRY_PADDING && MITIGATION_RETHUNK && OBJTOOL
+
+config CALL_THUNKS
+ def_bool n
+ select CALL_PADDING
+
+config PREFIX_SYMBOLS
+ def_bool y
+ 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
- speculative execution hardware vulnerabilities.
+ 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.
- If you say N, all mitigations will be disabled. You really
- should know what you are doing to say so.
+ Say 'Y', unless you really know what you are doing.
-if SPECULATION_MITIGATIONS
+if CPU_MITIGATIONS
-config PAGE_TABLE_ISOLATION
+config MITIGATION_PAGE_TABLE_ISOLATION
bool "Remove the kernel mapping in user mode"
default y
depends on (X86_64 || X86_PAE)
@@ -2464,9 +2459,9 @@ config PAGE_TABLE_ISOLATION
ensuring that the majority of kernel addresses are not mapped
into userspace.
- See Documentation/x86/pti.rst for more details.
+ See Documentation/arch/x86/pti.rst for more details.
-config RETPOLINE
+config MITIGATION_RETPOLINE
bool "Avoid speculative indirect branches in kernel"
select OBJTOOL if HAVE_OBJTOOL
default y
@@ -2476,9 +2471,9 @@ config RETPOLINE
branches. Requires a compiler with -mindirect-branch=thunk-extern
support for full protection. The kernel may run slower.
-config RETHUNK
+config MITIGATION_RETHUNK
bool "Enable return-thunks"
- depends on RETPOLINE && CC_HAS_RETURN_THUNK
+ depends on MITIGATION_RETPOLINE && CC_HAS_RETURN_THUNK
select OBJTOOL if HAVE_OBJTOOL
default y if X86_64
help
@@ -2487,21 +2482,52 @@ config RETHUNK
Requires a compiler with -mfunction-return=thunk-extern
support for full protection. The kernel may run slower.
-config CPU_UNRET_ENTRY
+config MITIGATION_UNRET_ENTRY
bool "Enable UNRET on kernel entry"
- depends on CPU_SUP_AMD && RETHUNK && X86_64
+ depends on CPU_SUP_AMD && MITIGATION_RETHUNK && X86_64
default y
help
Compile the kernel with support for the retbleed=unret mitigation.
-config CPU_IBPB_ENTRY
+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 mitigation.
+ Compile the kernel with support for the retbleed=ibpb and
+ spec_rstack_overflow={ibpb,ibpb-vmexit} mitigations.
-config CPU_IBRS_ENTRY
+config MITIGATION_IBRS_ENTRY
bool "Enable IBRS on kernel entry"
depends on CPU_SUP_INTEL && X86_64
default y
@@ -2510,7 +2536,14 @@ config CPU_IBRS_ENTRY
This mitigates both spectre_v2 and retbleed at great cost to
performance.
-config SLS
+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
@@ -2520,15 +2553,174 @@ config SLS
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 ARCH_ENABLE_MEMORY_HOTPLUG
-config ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE
- def_bool y
-
menu "Power management and ACPI options"
config ARCH_HIBERNATION_HEADER
@@ -2726,6 +2918,19 @@ config PCI_MMCONFIG
default y
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
@@ -2740,13 +2945,21 @@ config MMCONF_FAM10H
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.
@@ -2852,9 +3065,13 @@ config OLPC_XO15_SCI
- AC adapter status updates
- Battery status updates
+config GEODE_COMMON
+ bool
+
config ALIX
bool "PCEngines ALIX System Support (LED setup)"
select GPIOLIB
+ select GEODE_COMMON
help
This option enables system support for the PCEngines ALIX.
At present this just sets up LEDs for GPIO control on
@@ -2869,12 +3086,14 @@ config ALIX
config NET5501
bool "Soekris Engineering net5501 System Support (LEDS, GPIO, etc)"
select GPIOLIB
+ 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
This option enables system support for the Traverse Technologies GEOS.
@@ -2892,6 +3111,10 @@ endif # X86_32
config AMD_NB
def_bool y
+ depends on AMD_NODE
+
+config AMD_NODE
+ def_bool y
depends on CPU_SUP_AMD && PCI
endmenu
@@ -2909,6 +3132,15 @@ config IA32_EMULATION
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_EMULATION_DEFAULT_DISABLED
+ bool "IA32 emulation disabled by default"
+ default n
+ depends on IA32_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_ABI
bool "x32 ABI for 64-bit mode"
depends on X86_64
@@ -2945,4 +3177,6 @@ config HAVE_ATOMIC_IOMAP
source "arch/x86/kvm/Kconfig"
+source "arch/x86/Kconfig.cpufeatures"
+
source "arch/x86/Kconfig.assembler"