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.
+ 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
#
select ARCH_HAS_EARLY_DEBUG if KGDB
select ARCH_HAS_ELF_RANDOMIZE
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_SYNC_CORE_BEFORE_USERMODE
select ARCH_HAS_SYSCALL_WRAPPER
select ARCH_HAS_UBSAN_SANITIZE_ALL
+ select ARCH_HAS_VM_GET_PAGE_PROT
select ARCH_HAS_DEBUG_WX
select ARCH_HAS_ZONE_DMA_SET if EXPERT
select ARCH_HAVE_NMI_SAFE_CMPXCHG
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_LD_ORPHAN_WARN
select ARCH_WANTS_THP_SWAP if X86_64
select ARCH_HAS_PARANOID_L1D_FLUSH
select HAVE_CONTEXT_TRACKING if X86_64
select HAVE_CONTEXT_TRACKING_OFFSTACK if HAVE_CONTEXT_TRACKING
select HAVE_C_RECORDMCOUNT
- select HAVE_OBJTOOL_MCOUNT if STACK_VALIDATION
+ select HAVE_OBJTOOL_MCOUNT if HAVE_OBJTOOL
select HAVE_BUILDTIME_MCOUNT_SORT
select HAVE_DEBUG_KMEMLEAK
select HAVE_DMA_CONTIGUOUS
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_MOD_ARCH_SPECIFIC
select HAVE_MOVE_PMD
select HAVE_MOVE_PUD
+ select HAVE_NOINSTR_HACK if HAVE_OBJTOOL
select HAVE_NMI
+ select HAVE_NOINSTR_VALIDATION if HAVE_OBJTOOL
+ select HAVE_OBJTOOL if X86_64
select HAVE_OPTPROBES
select HAVE_PCSPKR_PLATFORM
select HAVE_PERF_EVENTS
select HAVE_PCI
select HAVE_PERF_REGS
select HAVE_PERF_USER_STACK_DUMP
- select MMU_GATHER_RCU_TABLE_FREE if PARAVIRT
+ select MMU_GATHER_RCU_TABLE_FREE if PARAVIRT
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_SETUP_PER_CPU_AREA
select HAVE_SOFTIRQ_ON_OWN_STACK
select HAVE_STACKPROTECTOR if CC_HAS_SANE_STACKPROTECTOR
- select HAVE_STACK_VALIDATION if X86_64
+ select HAVE_STACK_VALIDATION if HAVE_OBJTOOL
select HAVE_STATIC_CALL
- select HAVE_STATIC_CALL_INLINE if HAVE_STACK_VALIDATION
+ select HAVE_STATIC_CALL_INLINE if HAVE_OBJTOOL
select HAVE_PREEMPT_DYNAMIC_CALL
select HAVE_RSEQ
select HAVE_SYSCALL_TRACEPOINTS
+ select HAVE_UACCESS_VALIDATION if HAVE_OBJTOOL
select HAVE_UNSTABLE_SCHED_CLOCK
select HAVE_USER_RETURN_NOTIFIER
select HAVE_GENERIC_VDSO
select RTC_MC146818_LIB
select SPARSE_IRQ
select SRCU
- select STACK_VALIDATION if HAVE_STACK_VALIDATION && (HAVE_STATIC_CALL_INLINE || RETPOLINE)
select SYSCTL_EXCEPTION_TRACE
select THREAD_INFO_IN_TASK
select TRACE_IRQFLAGS_SUPPORT
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 or if it does not let us control
- the segment on 32-bit kernels.
+ 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 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
config 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
If you have one of these systems, or if you want to build a
generic distribution kernel, say Y here - otherwise say N.
-endif
+endif # X86_32
if X86_64
config X86_EXTENDED_PLATFORM
If you have one of these systems, or if you want to build a
generic distribution kernel, say Y here - otherwise say N.
-endif
+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
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.
+ Enable support for the Goldfish virtual platform used primarily
+ for Android development. Unless you are building for the Android
+ Goldfish emulator say N here.
config X86_INTEL_CE
bool "CE4100 TV platform"
IOT with small footprint and real-time features. More details can be
found in https://projectacrn.org/.
-endif #HYPERVISOR_GUEST
+config INTEL_TDX_GUEST
+ bool "Intel TDX (Trust Domain Extensions) - Guest Support"
+ depends on X86_64 && CPU_SUP_INTEL
+ depends on X86_X2APIC
+ select ARCH_HAS_CC_PLATFORM
+ select X86_MEM_ENCRYPT
+ select X86_MCE
+ 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"
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
prompt "Intel MCE features"
depends on X86_MCE && X86_LOCAL_APIC
help
- Additional support for intel specific MCE features such as
- the thermal monitor.
+ 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.
+ 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"
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 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.
+ 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.
+ 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"
config MICROCODE_INTEL
bool "Intel microcode loading support"
- depends on MICROCODE
+ depends on CPU_SUP_INTEL && MICROCODE
default MICROCODE
help
This options enables microcode patch loading support for Intel
config MICROCODE_AMD
bool "AMD microcode loading support"
- depends on MICROCODE
+ depends on CPU_SUP_AMD && MICROCODE
help
If you select this option, microcode patch loading support for AMD
processors will be enabled.
-config MICROCODE_OLD_INTERFACE
- bool "Ancient loading interface (DEPRECATED)"
+config MICROCODE_LATE_LOADING
+ bool "Late microcode loading (DANGEROUS)"
default n
depends on MICROCODE
help
- DO NOT USE THIS! This is the ancient /dev/cpu/microcode interface
- which was used by userspace tools like iucode_tool and microcode.ctl.
- It is inadequate because it runs too late to be able to properly
- load microcode on a machine and it needs special tools. Instead, you
- should've switched to the early loading method with the initrd or
- builtin microcode by now: Documentation/x86/microcode.rst
+ 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.
config X86_MSR
tristate "/dev/cpu/*/msr - Model-specific register support"
If supported, this is a high bandwidth, cryptographically
secure hardware random number generator.
-config X86_SMAP
- def_bool y
- prompt "Supervisor Mode Access Prevention" if EXPERT
- help
- Supervisor Mode Access Prevention (SMAP) is a security
- feature in newer Intel processors. There is a small
- performance cost if this enabled and turned on; there is
- also a small increase in the kernel size if this is enabled.
-
- If unsure, say Y.
-
config X86_UMIP
def_bool y
prompt "User Mode Instruction Prevention" if EXPERT
config X86_KERNEL_IBT
prompt "Indirect Branch Tracking"
bool
- depends on X86_64 && CC_HAS_IBT && STACK_VALIDATION
+ 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
help
Build the kernel with support for Indirect Branch Tracking, a
hardware support course-grain forward-edge Control Flow Integrity
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.
+ 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.
source "kernel/Kconfig.hz"
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.
+ 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
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.
+ 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
def_bool y
it can be used to assist security vulnerability exploitation.
This setting can be changed at boot time via the kernel command
- line parameter vsyscall=[emulate|xonly|none].
+ 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
If unsure, select "Emulate execution only".
- config LEGACY_VSYSCALL_EMULATE
- bool "Full emulation"
- help
- The kernel traps and emulates calls into the fixed vsyscall
- address mapping. This makes the mapping non-executable, but
- it still contains readable known contents, which could be
- used in certain rare security vulnerability exploits. This
- configuration is recommended when using legacy userspace
- that still uses vsyscalls along with legacy binary
- instrumentation tools that require code to be readable.
-
- An example of this type of legacy userspace is running
- Pin on an old binary that still uses vsyscalls.
-
config LEGACY_VSYSCALL_XONLY
bool "Emulate execution only"
help
endmenu
-
menu "Bus options (PCI etc.)"
choice
endmenu
-
menu "Binary Emulations"
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_AOUT
- tristate "IA32 a.out support"
- depends on IA32_EMULATION
- depends on BROKEN
- help
- Support old a.out binaries in the 32bit emulation.
-
config X86_X32_ABI
bool "x32 ABI for 64-bit mode"
depends on X86_64
def_bool y
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