config ARM64
|
def_bool y
|
select ACPI_CCA_REQUIRED if ACPI
|
select ACPI_GENERIC_GSI if ACPI
|
select ACPI_GTDT if ACPI
|
select ACPI_IORT if ACPI
|
select ACPI_REDUCED_HARDWARE_ONLY if ACPI
|
select ACPI_MCFG if ACPI
|
select ACPI_SPCR_TABLE if ACPI
|
select ACPI_PPTT if ACPI
|
select ARCH_CLOCKSOURCE_DATA
|
select ARCH_HAS_DEBUG_VIRTUAL
|
select ARCH_HAS_DEVMEM_IS_ALLOWED
|
select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI
|
select ARCH_HAS_ELF_RANDOMIZE
|
select ARCH_HAS_FAST_MULTIPLIER
|
select ARCH_HAS_FORTIFY_SOURCE
|
select ARCH_HAS_GCOV_PROFILE_ALL
|
select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
|
select ARCH_HAS_KCOV
|
select ARCH_HAS_MEMBARRIER_SYNC_CORE
|
select ARCH_HAS_PTE_SPECIAL
|
select ARCH_HAS_SET_MEMORY
|
select ARCH_HAS_SG_CHAIN
|
select ARCH_HAS_STRICT_KERNEL_RWX
|
select ARCH_HAS_STRICT_MODULE_RWX
|
select ARCH_HAS_SYSCALL_WRAPPER
|
select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
|
select ARCH_HAVE_NMI_SAFE_CMPXCHG
|
select ARCH_INLINE_READ_LOCK if !PREEMPT
|
select ARCH_INLINE_READ_LOCK_BH if !PREEMPT
|
select ARCH_INLINE_READ_LOCK_IRQ if !PREEMPT
|
select ARCH_INLINE_READ_LOCK_IRQSAVE if !PREEMPT
|
select ARCH_INLINE_READ_UNLOCK if !PREEMPT
|
select ARCH_INLINE_READ_UNLOCK_BH if !PREEMPT
|
select ARCH_INLINE_READ_UNLOCK_IRQ if !PREEMPT
|
select ARCH_INLINE_READ_UNLOCK_IRQRESTORE if !PREEMPT
|
select ARCH_INLINE_WRITE_LOCK if !PREEMPT
|
select ARCH_INLINE_WRITE_LOCK_BH if !PREEMPT
|
select ARCH_INLINE_WRITE_LOCK_IRQ if !PREEMPT
|
select ARCH_INLINE_WRITE_LOCK_IRQSAVE if !PREEMPT
|
select ARCH_INLINE_WRITE_UNLOCK if !PREEMPT
|
select ARCH_INLINE_WRITE_UNLOCK_BH if !PREEMPT
|
select ARCH_INLINE_WRITE_UNLOCK_IRQ if !PREEMPT
|
select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE if !PREEMPT
|
select ARCH_INLINE_SPIN_TRYLOCK if !PREEMPT
|
select ARCH_INLINE_SPIN_TRYLOCK_BH if !PREEMPT
|
select ARCH_INLINE_SPIN_LOCK if !PREEMPT
|
select ARCH_INLINE_SPIN_LOCK_BH if !PREEMPT
|
select ARCH_INLINE_SPIN_LOCK_IRQ if !PREEMPT
|
select ARCH_INLINE_SPIN_LOCK_IRQSAVE if !PREEMPT
|
select ARCH_INLINE_SPIN_UNLOCK if !PREEMPT
|
select ARCH_INLINE_SPIN_UNLOCK_BH if !PREEMPT
|
select ARCH_INLINE_SPIN_UNLOCK_IRQ if !PREEMPT
|
select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE if !PREEMPT
|
select ARCH_USE_CMPXCHG_LOCKREF
|
select ARCH_USE_QUEUED_RWLOCKS
|
select ARCH_USE_QUEUED_SPINLOCKS
|
select ARCH_SUPPORTS_MEMORY_FAILURE
|
select ARCH_SUPPORTS_LTO_CLANG
|
select ARCH_SUPPORTS_THINLTO
|
select ARCH_SUPPORTS_SHADOW_CALL_STACK if CC_HAVE_SHADOW_CALL_STACK
|
select ARCH_SUPPORTS_ATOMIC_RMW
|
select ARCH_SUPPORTS_INT128 if GCC_VERSION >= 50000 || CC_IS_CLANG
|
select ARCH_SUPPORTS_NUMA_BALANCING
|
select ARCH_WANT_COMPAT_IPC_PARSE_VERSION
|
select ARCH_WANT_FRAME_POINTERS
|
select ARCH_HAS_UBSAN_SANITIZE_ALL
|
select ARM_AMBA
|
select ARM_ARCH_TIMER
|
select ARM_GIC
|
select AUDIT_ARCH_COMPAT_GENERIC
|
select ARM_GIC_V2M if PCI
|
select ARM_GIC_V3
|
select ARM_GIC_V3_ITS if PCI
|
select ARM_PSCI_FW
|
select BUILDTIME_EXTABLE_SORT
|
select CLONE_BACKWARDS
|
select COMMON_CLK
|
select CPU_PM if (SUSPEND || CPU_IDLE)
|
select DCACHE_WORD_ACCESS
|
select DMA_DIRECT_OPS
|
select EDAC_SUPPORT
|
select FRAME_POINTER
|
select GENERIC_ALLOCATOR
|
select GENERIC_ARCH_TOPOLOGY
|
select GENERIC_CLOCKEVENTS
|
select GENERIC_CLOCKEVENTS_BROADCAST
|
select GENERIC_CPU_AUTOPROBE
|
select GENERIC_CPU_VULNERABILITIES
|
select GENERIC_EARLY_IOREMAP
|
select GENERIC_IDLE_POLL_SETUP
|
select GENERIC_IRQ_MULTI_HANDLER
|
select GENERIC_IRQ_PROBE
|
select GENERIC_IRQ_SHOW
|
select GENERIC_IRQ_SHOW_LEVEL
|
select GENERIC_PCI_IOMAP
|
select GENERIC_SCHED_CLOCK
|
select GENERIC_SMP_IDLE_THREAD
|
select GENERIC_STRNCPY_FROM_USER
|
select GENERIC_STRNLEN_USER
|
select GENERIC_TIME_VSYSCALL
|
select GENERIC_GETTIMEOFDAY
|
select HANDLE_DOMAIN_IRQ
|
select HARDIRQS_SW_RESEND
|
select HAVE_ACPI_APEI if (ACPI && EFI)
|
select HAVE_ALIGNED_STRUCT_PAGE if SLUB
|
select HAVE_ARCH_AUDITSYSCALL
|
select HAVE_ARCH_BITREVERSE
|
select HAVE_ARCH_HUGE_VMAP
|
select HAVE_ARCH_JUMP_LABEL
|
select HAVE_ARCH_KASAN if !(ARM64_16K_PAGES && ARM64_VA_BITS_48)
|
select HAVE_ARCH_KASAN_SW_TAGS if HAVE_ARCH_KASAN
|
select HAVE_ARCH_KGDB
|
select HAVE_ARCH_MMAP_RND_BITS
|
select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT
|
select HAVE_ARCH_PREL32_RELOCATIONS if !LTO_CLANG
|
select HAVE_ARCH_SECCOMP_FILTER
|
select HAVE_ARCH_STACKLEAK
|
select HAVE_ARCH_THREAD_STRUCT_WHITELIST
|
select HAVE_ARCH_TRACEHOOK
|
select HAVE_ARCH_TRANSPARENT_HUGEPAGE
|
select HAVE_ARCH_VMAP_STACK
|
select HAVE_ARM_SMCCC
|
select HAVE_EBPF_JIT
|
select HAVE_C_RECORDMCOUNT
|
select HAVE_CMPXCHG_DOUBLE
|
select HAVE_CMPXCHG_LOCAL
|
select HAVE_CONTEXT_TRACKING
|
select HAVE_DEBUG_BUGVERBOSE
|
select HAVE_DEBUG_KMEMLEAK
|
select HAVE_DMA_CONTIGUOUS
|
select HAVE_DYNAMIC_FTRACE
|
select HAVE_EFFICIENT_UNALIGNED_ACCESS
|
select HAVE_FTRACE_MCOUNT_RECORD
|
select HAVE_FUNCTION_TRACER
|
select HAVE_FUNCTION_GRAPH_TRACER if !SHADOW_CALL_STACK
|
select HAVE_GCC_PLUGINS
|
select HAVE_GENERIC_DMA_COHERENT
|
select HAVE_HW_BREAKPOINT if PERF_EVENTS
|
select HAVE_IRQ_TIME_ACCOUNTING
|
select HAVE_KERNEL_GZIP
|
select HAVE_KERNEL_LZ4
|
select HAVE_MEMBLOCK
|
select HAVE_MEMBLOCK_NODE_MAP if NUMA
|
select HAVE_NMI
|
select HAVE_PATA_PLATFORM
|
select HAVE_PERF_EVENTS
|
select HAVE_PERF_REGS
|
select HAVE_PERF_USER_STACK_DUMP
|
select HAVE_PREEMPT_LAZY
|
select HAVE_REGS_AND_STACK_ACCESS_API
|
select HAVE_RCU_TABLE_FREE
|
select HAVE_RSEQ
|
select HAVE_STACKPROTECTOR
|
select HAVE_SYSCALL_TRACEPOINTS
|
select HAVE_KPROBES
|
select HAVE_KRETPROBES
|
select HAVE_GENERIC_VDSO
|
select IOMMU_DMA if IOMMU_SUPPORT
|
select IRQ_DOMAIN
|
select IRQ_FORCED_THREADING
|
select MODULES_USE_ELF_RELA
|
select MULTI_IRQ_HANDLER
|
select NEED_DMA_MAP_STATE
|
select NEED_SG_DMA_LENGTH
|
select NO_BOOTMEM
|
select OF
|
select OF_EARLY_FLATTREE
|
select OF_RESERVED_MEM
|
select PCI_ECAM if ACPI
|
select POWER_RESET
|
select POWER_SUPPLY
|
select REFCOUNT_FULL
|
select SPARSE_IRQ
|
select SWIOTLB
|
select SYSCTL_EXCEPTION_TRACE
|
select THREAD_INFO_IN_TASK
|
help
|
ARM 64-bit (AArch64) Linux support.
|
|
config 64BIT
|
def_bool y
|
|
config MMU
|
def_bool y
|
|
config ARM64_PAGE_SHIFT
|
int
|
default 16 if ARM64_64K_PAGES
|
default 14 if ARM64_16K_PAGES
|
default 12
|
|
config ARM64_CONT_SHIFT
|
int
|
default 5 if ARM64_64K_PAGES
|
default 7 if ARM64_16K_PAGES
|
default 4
|
|
config ARCH_MMAP_RND_BITS_MIN
|
default 14 if ARM64_64K_PAGES
|
default 16 if ARM64_16K_PAGES
|
default 18
|
|
# max bits determined by the following formula:
|
# VA_BITS - PAGE_SHIFT - 3
|
config ARCH_MMAP_RND_BITS_MAX
|
default 19 if ARM64_VA_BITS=36
|
default 24 if ARM64_VA_BITS=39
|
default 27 if ARM64_VA_BITS=42
|
default 30 if ARM64_VA_BITS=47
|
default 29 if ARM64_VA_BITS=48 && ARM64_64K_PAGES
|
default 31 if ARM64_VA_BITS=48 && ARM64_16K_PAGES
|
default 33 if ARM64_VA_BITS=48
|
default 14 if ARM64_64K_PAGES
|
default 16 if ARM64_16K_PAGES
|
default 18
|
|
config ARCH_MMAP_RND_COMPAT_BITS_MIN
|
default 7 if ARM64_64K_PAGES
|
default 9 if ARM64_16K_PAGES
|
default 11
|
|
config ARCH_MMAP_RND_COMPAT_BITS_MAX
|
default 16
|
|
config NO_IOPORT_MAP
|
def_bool y if !PCI
|
|
config STACKTRACE_SUPPORT
|
def_bool y
|
|
config ILLEGAL_POINTER_VALUE
|
hex
|
default 0xdead000000000000
|
|
config LOCKDEP_SUPPORT
|
def_bool y
|
|
config TRACE_IRQFLAGS_SUPPORT
|
def_bool y
|
|
config RWSEM_XCHGADD_ALGORITHM
|
def_bool y
|
|
config GENERIC_BUG
|
def_bool y
|
depends on BUG
|
|
config GENERIC_BUG_RELATIVE_POINTERS
|
def_bool y
|
depends on GENERIC_BUG
|
|
config GENERIC_HWEIGHT
|
def_bool y
|
|
config GENERIC_CSUM
|
def_bool y
|
|
config GENERIC_CALIBRATE_DELAY
|
def_bool y
|
|
config ZONE_DMA32
|
bool "Support DMA32 zone" if EXPERT
|
default y
|
|
config HAVE_GENERIC_GUP
|
def_bool y
|
|
config SMP
|
def_bool y
|
|
config KERNEL_MODE_NEON
|
def_bool y
|
|
config FIX_EARLYCON_MEM
|
def_bool y
|
|
config PGTABLE_LEVELS
|
int
|
default 2 if ARM64_16K_PAGES && ARM64_VA_BITS_36
|
default 2 if ARM64_64K_PAGES && ARM64_VA_BITS_42
|
default 3 if ARM64_64K_PAGES && ARM64_VA_BITS_48
|
default 3 if ARM64_4K_PAGES && ARM64_VA_BITS_39
|
default 3 if ARM64_16K_PAGES && ARM64_VA_BITS_47
|
default 4 if !ARM64_64K_PAGES && ARM64_VA_BITS_48
|
|
config ARCH_SUPPORTS_UPROBES
|
def_bool y
|
|
config ARCH_PROC_KCORE_TEXT
|
def_bool y
|
|
source "arch/arm64/Kconfig.platforms"
|
|
menu "Bus support"
|
|
config PCI
|
bool "PCI support"
|
help
|
This feature enables support for PCI bus system. If you say Y
|
here, the kernel will include drivers and infrastructure code
|
to support PCI bus devices.
|
|
config PCI_DOMAINS
|
def_bool PCI
|
|
config PCI_DOMAINS_GENERIC
|
def_bool PCI
|
|
config PCI_SYSCALL
|
def_bool PCI
|
|
source "drivers/pci/Kconfig"
|
|
endmenu
|
|
menu "Kernel Features"
|
|
menu "ARM errata workarounds via the alternatives framework"
|
|
config ARM64_ERRATUM_826319
|
bool "Cortex-A53: 826319: System might deadlock if a write cannot complete until read data is accepted"
|
default y
|
help
|
This option adds an alternative code sequence to work around ARM
|
erratum 826319 on Cortex-A53 parts up to r0p2 with an AMBA 4 ACE or
|
AXI master interface and an L2 cache.
|
|
If a Cortex-A53 uses an AMBA AXI4 ACE interface to other processors
|
and is unable to accept a certain write via this interface, it will
|
not progress on read data presented on the read data channel and the
|
system can deadlock.
|
|
The workaround promotes data cache clean instructions to
|
data cache clean-and-invalidate.
|
Please note that this does not necessarily enable the workaround,
|
as it depends on the alternative framework, which will only patch
|
the kernel if an affected CPU is detected.
|
|
If unsure, say Y.
|
|
config ARM64_ERRATUM_827319
|
bool "Cortex-A53: 827319: Data cache clean instructions might cause overlapping transactions to the interconnect"
|
default y
|
help
|
This option adds an alternative code sequence to work around ARM
|
erratum 827319 on Cortex-A53 parts up to r0p2 with an AMBA 5 CHI
|
master interface and an L2 cache.
|
|
Under certain conditions this erratum can cause a clean line eviction
|
to occur at the same time as another transaction to the same address
|
on the AMBA 5 CHI interface, which can cause data corruption if the
|
interconnect reorders the two transactions.
|
|
The workaround promotes data cache clean instructions to
|
data cache clean-and-invalidate.
|
Please note that this does not necessarily enable the workaround,
|
as it depends on the alternative framework, which will only patch
|
the kernel if an affected CPU is detected.
|
|
If unsure, say Y.
|
|
config ARM64_ERRATUM_824069
|
bool "Cortex-A53: 824069: Cache line might not be marked as clean after a CleanShared snoop"
|
default y
|
help
|
This option adds an alternative code sequence to work around ARM
|
erratum 824069 on Cortex-A53 parts up to r0p2 when it is connected
|
to a coherent interconnect.
|
|
If a Cortex-A53 processor is executing a store or prefetch for
|
write instruction at the same time as a processor in another
|
cluster is executing a cache maintenance operation to the same
|
address, then this erratum might cause a clean cache line to be
|
incorrectly marked as dirty.
|
|
The workaround promotes data cache clean instructions to
|
data cache clean-and-invalidate.
|
Please note that this option does not necessarily enable the
|
workaround, as it depends on the alternative framework, which will
|
only patch the kernel if an affected CPU is detected.
|
|
If unsure, say Y.
|
|
config ARM64_ERRATUM_819472
|
bool "Cortex-A53: 819472: Store exclusive instructions might cause data corruption"
|
default y
|
help
|
This option adds an alternative code sequence to work around ARM
|
erratum 819472 on Cortex-A53 parts up to r0p1 with an L2 cache
|
present when it is connected to a coherent interconnect.
|
|
If the processor is executing a load and store exclusive sequence at
|
the same time as a processor in another cluster is executing a cache
|
maintenance operation to the same address, then this erratum might
|
cause data corruption.
|
|
The workaround promotes data cache clean instructions to
|
data cache clean-and-invalidate.
|
Please note that this does not necessarily enable the workaround,
|
as it depends on the alternative framework, which will only patch
|
the kernel if an affected CPU is detected.
|
|
If unsure, say Y.
|
|
config ARM64_ERRATUM_832075
|
bool "Cortex-A57: 832075: possible deadlock on mixing exclusive memory accesses with device loads"
|
default y
|
help
|
This option adds an alternative code sequence to work around ARM
|
erratum 832075 on Cortex-A57 parts up to r1p2.
|
|
Affected Cortex-A57 parts might deadlock when exclusive load/store
|
instructions to Write-Back memory are mixed with Device loads.
|
|
The workaround is to promote device loads to use Load-Acquire
|
semantics.
|
Please note that this does not necessarily enable the workaround,
|
as it depends on the alternative framework, which will only patch
|
the kernel if an affected CPU is detected.
|
|
If unsure, say Y.
|
|
config ARM64_ERRATUM_834220
|
bool "Cortex-A57: 834220: Stage 2 translation fault might be incorrectly reported in presence of a Stage 1 fault"
|
depends on KVM
|
default y
|
help
|
This option adds an alternative code sequence to work around ARM
|
erratum 834220 on Cortex-A57 parts up to r1p2.
|
|
Affected Cortex-A57 parts might report a Stage 2 translation
|
fault as the result of a Stage 1 fault for load crossing a
|
page boundary when there is a permission or device memory
|
alignment fault at Stage 1 and a translation fault at Stage 2.
|
|
The workaround is to verify that the Stage 1 translation
|
doesn't generate a fault before handling the Stage 2 fault.
|
Please note that this does not necessarily enable the workaround,
|
as it depends on the alternative framework, which will only patch
|
the kernel if an affected CPU is detected.
|
|
If unsure, say Y.
|
|
config ARM64_ERRATUM_845719
|
bool "Cortex-A53: 845719: a load might read incorrect data"
|
depends on COMPAT
|
default y
|
help
|
This option adds an alternative code sequence to work around ARM
|
erratum 845719 on Cortex-A53 parts up to r0p4.
|
|
When running a compat (AArch32) userspace on an affected Cortex-A53
|
part, a load at EL0 from a virtual address that matches the bottom 32
|
bits of the virtual address used by a recent load at (AArch64) EL1
|
might return incorrect data.
|
|
The workaround is to write the contextidr_el1 register on exception
|
return to a 32-bit task.
|
Please note that this does not necessarily enable the workaround,
|
as it depends on the alternative framework, which will only patch
|
the kernel if an affected CPU is detected.
|
|
If unsure, say Y.
|
|
config ARM64_ERRATUM_843419
|
bool "Cortex-A53: 843419: A load or store might access an incorrect address"
|
default y
|
select ARM64_MODULE_PLTS if MODULES
|
help
|
This option links the kernel with '--fix-cortex-a53-843419' and
|
enables PLT support to replace certain ADRP instructions, which can
|
cause subsequent memory accesses to use an incorrect address on
|
Cortex-A53 parts up to r0p4.
|
|
If unsure, say Y.
|
|
config ARM64_ERRATUM_1024718
|
bool "Cortex-A55: 1024718: Update of DBM/AP bits without break before make might result in incorrect update"
|
default y
|
help
|
This option adds work around for Arm Cortex-A55 Erratum 1024718.
|
|
Affected Cortex-A55 cores (all revisions) could cause incorrect
|
update of the hardware dirty bit when the DBM/AP bits are updated
|
without a break-before-make. The work around is to disable the usage
|
of hardware DBM locally on the affected cores. CPUs not affected by
|
erratum will continue to use the feature.
|
|
If unsure, say Y.
|
|
config ARM64_ERRATUM_1463225
|
bool "Cortex-A76: Software Step might prevent interrupt recognition"
|
default y
|
help
|
This option adds a workaround for Arm Cortex-A76 erratum 1463225.
|
|
On the affected Cortex-A76 cores (r0p0 to r3p1), software stepping
|
of a system call instruction (SVC) can prevent recognition of
|
subsequent interrupts when software stepping is disabled in the
|
exception handler of the system call and either kernel debugging
|
is enabled or VHE is in use.
|
|
Work around the erratum by triggering a dummy step exception
|
when handling a system call from a task that is being stepped
|
in a VHE configuration of the kernel.
|
|
If unsure, say Y.
|
|
config ARM64_ERRATUM_1542419
|
bool "Neoverse-N1: workaround mis-ordering of instruction fetches"
|
default y
|
help
|
This option adds a workaround for ARM Neoverse-N1 erratum
|
1542419.
|
|
Affected Neoverse-N1 cores could execute a stale instruction when
|
modified by another CPU. The workaround depends on a firmware
|
counterpart.
|
|
Workaround the issue by hiding the DIC feature from EL0. This
|
forces user-space to perform cache maintenance.
|
|
If unsure, say Y.
|
|
config CAVIUM_ERRATUM_22375
|
bool "Cavium erratum 22375, 24313"
|
default y
|
help
|
Enable workaround for erratum 22375, 24313.
|
|
This implements two gicv3-its errata workarounds for ThunderX. Both
|
with small impact affecting only ITS table allocation.
|
|
erratum 22375: only alloc 8MB table size
|
erratum 24313: ignore memory access type
|
|
The fixes are in ITS initialization and basically ignore memory access
|
type and table size provided by the TYPER and BASER registers.
|
|
If unsure, say Y.
|
|
config CAVIUM_ERRATUM_23144
|
bool "Cavium erratum 23144: ITS SYNC hang on dual socket system"
|
depends on NUMA
|
default y
|
help
|
ITS SYNC command hang for cross node io and collections/cpu mapping.
|
|
If unsure, say Y.
|
|
config CAVIUM_ERRATUM_23154
|
bool "Cavium erratum 23154: Access to ICC_IAR1_EL1 is not sync'ed"
|
default y
|
help
|
The gicv3 of ThunderX requires a modified version for
|
reading the IAR status to ensure data synchronization
|
(access to icc_iar1_el1 is not sync'ed before and after).
|
|
If unsure, say Y.
|
|
config CAVIUM_ERRATUM_27456
|
bool "Cavium erratum 27456: Broadcast TLBI instructions may cause icache corruption"
|
default y
|
help
|
On ThunderX T88 pass 1.x through 2.1 parts, broadcast TLBI
|
instructions may cause the icache to become corrupted if it
|
contains data for a non-current ASID. The fix is to
|
invalidate the icache when changing the mm context.
|
|
If unsure, say Y.
|
|
config CAVIUM_ERRATUM_30115
|
bool "Cavium erratum 30115: Guest may disable interrupts in host"
|
default y
|
help
|
On ThunderX T88 pass 1.x through 2.2, T81 pass 1.0 through
|
1.2, and T83 Pass 1.0, KVM guest execution may disable
|
interrupts in host. Trapping both GICv3 group-0 and group-1
|
accesses sidesteps the issue.
|
|
If unsure, say Y.
|
|
config QCOM_FALKOR_ERRATUM_1003
|
bool "Falkor E1003: Incorrect translation due to ASID change"
|
default y
|
help
|
On Falkor v1, an incorrect ASID may be cached in the TLB when ASID
|
and BADDR are changed together in TTBRx_EL1. Since we keep the ASID
|
in TTBR1_EL1, this situation only occurs in the entry trampoline and
|
then only for entries in the walk cache, since the leaf translation
|
is unchanged. Work around the erratum by invalidating the walk cache
|
entries for the trampoline before entering the kernel proper.
|
|
config QCOM_FALKOR_ERRATUM_1009
|
bool "Falkor E1009: Prematurely complete a DSB after a TLBI"
|
default y
|
help
|
On Falkor v1, the CPU may prematurely complete a DSB following a
|
TLBI xxIS invalidate maintenance operation. Repeat the TLBI operation
|
one more time to fix the issue.
|
|
If unsure, say Y.
|
|
config QCOM_QDF2400_ERRATUM_0065
|
bool "QDF2400 E0065: Incorrect GITS_TYPER.ITT_Entry_size"
|
default y
|
help
|
On Qualcomm Datacenter Technologies QDF2400 SoC, ITS hardware reports
|
ITE size incorrectly. The GITS_TYPER.ITT_Entry_size field should have
|
been indicated as 16Bytes (0xf), not 8Bytes (0x7).
|
|
If unsure, say Y.
|
|
config SOCIONEXT_SYNQUACER_PREITS
|
bool "Socionext Synquacer: Workaround for GICv3 pre-ITS"
|
default y
|
help
|
Socionext Synquacer SoCs implement a separate h/w block to generate
|
MSI doorbell writes with non-zero values for the device ID.
|
|
If unsure, say Y.
|
|
config HISILICON_ERRATUM_161600802
|
bool "Hip07 161600802: Erroneous redistributor VLPI base"
|
default y
|
help
|
The HiSilicon Hip07 SoC usees the wrong redistributor base
|
when issued ITS commands such as VMOVP and VMAPP, and requires
|
a 128kB offset to be applied to the target address in this commands.
|
|
If unsure, say Y.
|
|
config QCOM_FALKOR_ERRATUM_E1041
|
bool "Falkor E1041: Speculative instruction fetches might cause errant memory access"
|
default y
|
help
|
Falkor CPU may speculatively fetch instructions from an improper
|
memory location when MMU translation is changed from SCTLR_ELn[M]=1
|
to SCTLR_ELn[M]=0. Prefix an ISB instruction to fix the problem.
|
|
If unsure, say Y.
|
|
endmenu
|
|
|
choice
|
prompt "Page size"
|
default ARM64_4K_PAGES
|
help
|
Page size (translation granule) configuration.
|
|
config ARM64_4K_PAGES
|
bool "4KB"
|
help
|
This feature enables 4KB pages support.
|
|
config ARM64_16K_PAGES
|
bool "16KB"
|
help
|
The system will use 16KB pages support. AArch32 emulation
|
requires applications compiled with 16K (or a multiple of 16K)
|
aligned segments.
|
|
config ARM64_64K_PAGES
|
bool "64KB"
|
help
|
This feature enables 64KB pages support (4KB by default)
|
allowing only two levels of page tables and faster TLB
|
look-up. AArch32 emulation requires applications compiled
|
with 64K aligned segments.
|
|
endchoice
|
|
choice
|
prompt "Virtual address space size"
|
default ARM64_VA_BITS_39 if ARM64_4K_PAGES
|
default ARM64_VA_BITS_47 if ARM64_16K_PAGES
|
default ARM64_VA_BITS_42 if ARM64_64K_PAGES
|
help
|
Allows choosing one of multiple possible virtual address
|
space sizes. The level of translation table is determined by
|
a combination of page size and virtual address space size.
|
|
config ARM64_VA_BITS_36
|
bool "36-bit" if EXPERT
|
depends on ARM64_16K_PAGES
|
|
config ARM64_VA_BITS_39
|
bool "39-bit"
|
depends on ARM64_4K_PAGES
|
|
config ARM64_VA_BITS_42
|
bool "42-bit"
|
depends on ARM64_64K_PAGES
|
|
config ARM64_VA_BITS_47
|
bool "47-bit"
|
depends on ARM64_16K_PAGES
|
|
config ARM64_VA_BITS_48
|
bool "48-bit"
|
|
endchoice
|
|
config ARM64_VA_BITS
|
int
|
default 36 if ARM64_VA_BITS_36
|
default 39 if ARM64_VA_BITS_39
|
default 42 if ARM64_VA_BITS_42
|
default 47 if ARM64_VA_BITS_47
|
default 48 if ARM64_VA_BITS_48
|
|
choice
|
prompt "Physical address space size"
|
default ARM64_PA_BITS_48
|
help
|
Choose the maximum physical address range that the kernel will
|
support.
|
|
config ARM64_PA_BITS_48
|
bool "48-bit"
|
|
config ARM64_PA_BITS_52
|
bool "52-bit (ARMv8.2)"
|
depends on ARM64_64K_PAGES
|
depends on ARM64_PAN || !ARM64_SW_TTBR0_PAN
|
help
|
Enable support for a 52-bit physical address space, introduced as
|
part of the ARMv8.2-LPA extension.
|
|
With this enabled, the kernel will also continue to work on CPUs that
|
do not support ARMv8.2-LPA, but with some added memory overhead (and
|
minor performance overhead).
|
|
endchoice
|
|
config ARM64_PA_BITS
|
int
|
default 48 if ARM64_PA_BITS_48
|
default 52 if ARM64_PA_BITS_52
|
|
config CPU_BIG_ENDIAN
|
bool "Build big-endian kernel"
|
help
|
Say Y if you plan on running a kernel in big-endian mode.
|
|
config SCHED_MC
|
bool "Multi-core scheduler support"
|
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_SMT
|
bool "SMT scheduler support"
|
help
|
Improves the CPU scheduler's decision making when dealing with
|
MultiThreading at a cost of slightly increased overhead in some
|
places. If unsure say N here.
|
|
config NR_CPUS
|
int "Maximum number of CPUs (2-4096)"
|
range 2 4096
|
# These have to remain sorted largest to smallest
|
default "64"
|
|
config HOTPLUG_CPU
|
bool "Support for hot-pluggable CPUs"
|
select GENERIC_IRQ_MIGRATION
|
help
|
Say Y here to experiment with turning CPUs off and on. CPUs
|
can be controlled through /sys/devices/system/cpu.
|
|
# Common NUMA Features
|
config NUMA
|
bool "Numa Memory Allocation and Scheduler Support"
|
select ACPI_NUMA if ACPI
|
select OF_NUMA
|
help
|
Enable NUMA (Non Uniform Memory Access) support.
|
|
The kernel will try to allocate memory used by a CPU on the
|
local memory of the CPU and add some more
|
NUMA awareness to the kernel.
|
|
config NODES_SHIFT
|
int "Maximum NUMA Nodes (as a power of 2)"
|
range 1 10
|
default "2"
|
depends on NEED_MULTIPLE_NODES
|
help
|
Specify the maximum number of NUMA Nodes available on the target
|
system. Increases memory reserved to accommodate various tables.
|
|
config USE_PERCPU_NUMA_NODE_ID
|
def_bool y
|
depends on NUMA
|
|
config HAVE_SETUP_PER_CPU_AREA
|
def_bool y
|
depends on NUMA
|
|
config NEED_PER_CPU_EMBED_FIRST_CHUNK
|
def_bool y
|
depends on NUMA
|
|
config HOLES_IN_ZONE
|
def_bool y
|
|
source kernel/Kconfig.hz
|
|
config ARCH_SUPPORTS_DEBUG_PAGEALLOC
|
def_bool y
|
|
config ARCH_HAS_HOLES_MEMORYMODEL
|
def_bool y if SPARSEMEM
|
|
config ARCH_SPARSEMEM_ENABLE
|
def_bool y
|
select SPARSEMEM_VMEMMAP_ENABLE
|
|
config ARCH_SPARSEMEM_DEFAULT
|
def_bool ARCH_SPARSEMEM_ENABLE
|
|
config ARCH_SELECT_MEMORY_MODEL
|
def_bool ARCH_SPARSEMEM_ENABLE
|
|
config ARCH_FLATMEM_ENABLE
|
def_bool !NUMA
|
|
config HAVE_ARCH_PFN_VALID
|
def_bool ARCH_HAS_HOLES_MEMORYMODEL || !SPARSEMEM
|
|
config HW_PERF_EVENTS
|
def_bool y
|
depends on ARM_PMU
|
|
config SYS_SUPPORTS_HUGETLBFS
|
def_bool y
|
|
config ARCH_WANT_HUGE_PMD_SHARE
|
def_bool y if ARM64_4K_PAGES || (ARM64_16K_PAGES && !ARM64_VA_BITS_36)
|
|
config ARCH_HAS_CACHE_LINE_SIZE
|
def_bool y
|
|
|
# Supported by clang >= 7.0
|
config CC_HAVE_SHADOW_CALL_STACK
|
def_bool $(cc-option, -fsanitize=shadow-call-stack -ffixed-x18)
|
|
config ARM64_DMA_USE_IOMMU
|
bool "ARM64 DMA iommu integration"
|
select ARM_HAS_SG_CHAIN
|
select NEED_SG_DMA_LENGTH
|
help
|
Enable using iommu through the standard dma apis.
|
dma_alloc_coherent() will allocate scatter-gather memory
|
which is made virtually contiguous via iommu.
|
Enable if system contains IOMMU hardware.
|
|
if ARM64_DMA_USE_IOMMU
|
|
config ARM64_DMA_IOMMU_ALIGNMENT
|
int "Maximum PAGE_SIZE order of alignment for DMA IOMMU buffers"
|
range 4 9
|
default 9
|
help
|
DMA mapping framework by default aligns all buffers to the smallest
|
PAGE_SIZE order which is greater than or equal to the requested buffer
|
size. This works well for buffers up to a few hundreds kilobytes, but
|
for larger buffers it just a waste of address space. Drivers which has
|
relatively small addressing window (like 64Mib) might run out of
|
virtual space with just a few allocations.
|
|
With this parameter you can specify the maximum PAGE_SIZE order for
|
DMA IOMMU buffers. Larger buffers will be aligned only to this
|
specified order. The order is expressed as a power of two multiplied
|
by the PAGE_SIZE.
|
|
endif
|
|
config SECCOMP
|
bool "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 PARAVIRT
|
bool "Enable paravirtualization code"
|
help
|
This changes the kernel so it can modify itself when it is run
|
under a hypervisor, potentially improving performance significantly
|
over full virtualization.
|
|
config PARAVIRT_TIME_ACCOUNTING
|
bool "Paravirtual steal time accounting"
|
select PARAVIRT
|
default n
|
help
|
Select this option to enable fine granularity task steal time
|
accounting. Time spent executing other tasks in parallel with
|
the current vCPU is discounted from the vCPU power. To account for
|
that, there can be a small performance impact.
|
|
If in doubt, say N here.
|
|
config KEXEC
|
depends on PM_SLEEP_SMP
|
select KEXEC_CORE
|
bool "kexec system call"
|
---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.
|
|
config CRASH_DUMP
|
bool "Build kdump crash kernel"
|
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.
|
|
For more details see Documentation/kdump/kdump.txt
|
|
config XEN_DOM0
|
def_bool y
|
depends on XEN
|
|
config XEN
|
bool "Xen guest support on ARM64"
|
depends on ARM64 && OF
|
select SWIOTLB_XEN
|
select PARAVIRT
|
help
|
Say Y if you want to run Linux in a Virtual Machine on Xen on ARM64.
|
|
config FORCE_MAX_ZONEORDER
|
int
|
default "14" if (ARM64_64K_PAGES && TRANSPARENT_HUGEPAGE)
|
default "12" if (ARM64_16K_PAGES && TRANSPARENT_HUGEPAGE)
|
default "11"
|
help
|
The kernel memory allocator divides physically contiguous memory
|
blocks into "zones", where each zone is a power of two number of
|
pages. This option selects the largest power of two that the kernel
|
keeps in the memory allocator. If you need to allocate very large
|
blocks of physically contiguous memory, then you may need to
|
increase this value.
|
|
This config option is actually maximum order plus one. For example,
|
a value of 11 means that the largest free memory block is 2^10 pages.
|
|
We make sure that we can allocate upto a HugePage size for each configuration.
|
Hence we have :
|
MAX_ORDER = (PMD_SHIFT - PAGE_SHIFT) + 1 => PAGE_SHIFT - 2
|
|
However for 4K, we choose a higher default value, 11 as opposed to 10, giving us
|
4M allocations matching the default size used by generic code.
|
|
config UNMAP_KERNEL_AT_EL0
|
bool "Unmap kernel when running in userspace (aka \"KAISER\")" if EXPERT
|
default y
|
help
|
Speculation attacks against some high-performance processors can
|
be used to bypass MMU permission checks and leak kernel data to
|
userspace. This can be defended against by unmapping the kernel
|
when running in userspace, mapping it back in on exception entry
|
via a trampoline page in the vector table.
|
|
If unsure, say Y.
|
|
config HARDEN_BRANCH_PREDICTOR
|
bool "Harden the branch predictor against aliasing attacks" if EXPERT
|
default y
|
help
|
Speculation attacks against some high-performance processors rely on
|
being able to manipulate the branch predictor for a victim context by
|
executing aliasing branches in the attacker context. Such attacks
|
can be partially mitigated against by clearing internal branch
|
predictor state and limiting the prediction logic in some situations.
|
|
This config option will take CPU-specific actions to harden the
|
branch predictor against aliasing attacks and may rely on specific
|
instruction sequences or control bits being set by the system
|
firmware.
|
|
If unsure, say Y.
|
|
config HARDEN_EL2_VECTORS
|
bool "Harden EL2 vector mapping against system register leak" if EXPERT
|
default y
|
help
|
Speculation attacks against some high-performance processors can
|
be used to leak privileged information such as the vector base
|
register, resulting in a potential defeat of the EL2 layout
|
randomization.
|
|
This config option will map the vectors to a fixed location,
|
independent of the EL2 code mapping, so that revealing VBAR_EL2
|
to an attacker does not give away any extra information. This
|
only gets enabled on affected CPUs.
|
|
If unsure, say Y.
|
|
config ARM64_SSBD
|
bool "Speculative Store Bypass Disable" if EXPERT
|
default y
|
help
|
This enables mitigation of the bypassing of previous stores
|
by speculative loads.
|
|
If unsure, say Y.
|
|
config ARM64_TAGGED_ADDR_ABI
|
bool "Enable the tagged user addresses syscall ABI"
|
default y
|
help
|
When this option is enabled, user applications can opt in to a
|
relaxed ABI via prctl() allowing tagged addresses to be passed
|
to system calls as pointer arguments. For details, see
|
Documentation/arm64/tagged-address-abi.rst.
|
|
config COMPAT_VDSO
|
bool "Enable vDSO for 32-bit applications"
|
depends on !CPU_BIG_ENDIAN && "$(CROSS_COMPILE_COMPAT)" != ""
|
select GENERIC_COMPAT_VDSO
|
default y
|
help
|
Place in the process address space of 32-bit applications an
|
ELF shared object providing fast implementations of gettimeofday
|
and clock_gettime.
|
|
You must have a 32-bit build of glibc 2.22 or later for programs
|
to seamlessly take advantage of this.
|
|
menuconfig ARMV8_DEPRECATED
|
bool "Emulate deprecated/obsolete ARMv8 instructions"
|
depends on COMPAT
|
depends on SYSCTL
|
help
|
Legacy software support may require certain instructions
|
that have been deprecated or obsoleted in the architecture.
|
|
Enable this config to enable selective emulation of these
|
features.
|
|
If unsure, say Y
|
|
if ARMV8_DEPRECATED
|
|
config SWP_EMULATION
|
bool "Emulate SWP/SWPB instructions"
|
help
|
ARMv8 obsoletes the use of A32 SWP/SWPB instructions such that
|
they are always undefined. Say Y here to enable software
|
emulation of these instructions for userspace using LDXR/STXR.
|
|
In some older versions of glibc [<=2.8] SWP is used during futex
|
trylock() operations with the assumption that the code will not
|
be preempted. This invalid assumption may be more likely to fail
|
with SWP emulation enabled, leading to deadlock of the user
|
application.
|
|
NOTE: when accessing uncached shared regions, LDXR/STXR rely
|
on an external transaction monitoring block called a global
|
monitor to maintain update atomicity. If your system does not
|
implement a global monitor, this option can cause programs that
|
perform SWP operations to uncached memory to deadlock.
|
|
If unsure, say Y
|
|
config CP15_BARRIER_EMULATION
|
bool "Emulate CP15 Barrier instructions"
|
help
|
The CP15 barrier instructions - CP15ISB, CP15DSB, and
|
CP15DMB - are deprecated in ARMv8 (and ARMv7). It is
|
strongly recommended to use the ISB, DSB, and DMB
|
instructions instead.
|
|
Say Y here to enable software emulation of these
|
instructions for AArch32 userspace code. When this option is
|
enabled, CP15 barrier usage is traced which can help
|
identify software that needs updating.
|
|
If unsure, say Y
|
|
config SETEND_EMULATION
|
bool "Emulate SETEND instruction"
|
help
|
The SETEND instruction alters the data-endianness of the
|
AArch32 EL0, and is deprecated in ARMv8.
|
|
Say Y here to enable software emulation of the instruction
|
for AArch32 userspace code.
|
|
Note: All the cpus on the system must have mixed endian support at EL0
|
for this feature to be enabled. If a new CPU - which doesn't support mixed
|
endian - is hotplugged in after this feature has been enabled, there could
|
be unexpected results in the applications.
|
|
If unsure, say Y
|
endif
|
|
config ARM64_SW_TTBR0_PAN
|
bool "Emulate Privileged Access Never using TTBR0_EL1 switching"
|
help
|
Enabling this option prevents the kernel from accessing
|
user-space memory directly by pointing TTBR0_EL1 to a reserved
|
zeroed area and reserved ASID. The user access routines
|
restore the valid TTBR0_EL1 temporarily.
|
|
menu "ARMv8.1 architectural features"
|
|
config ARM64_HW_AFDBM
|
bool "Support for hardware updates of the Access and Dirty page flags"
|
default y
|
help
|
The ARMv8.1 architecture extensions introduce support for
|
hardware updates of the access and dirty information in page
|
table entries. When enabled in TCR_EL1 (HA and HD bits) on
|
capable processors, accesses to pages with PTE_AF cleared will
|
set this bit instead of raising an access flag fault.
|
Similarly, writes to read-only pages with the DBM bit set will
|
clear the read-only bit (AP[2]) instead of raising a
|
permission fault.
|
|
Kernels built with this configuration option enabled continue
|
to work on pre-ARMv8.1 hardware and the performance impact is
|
minimal. If unsure, say Y.
|
|
config ARM64_PAN
|
bool "Enable support for Privileged Access Never (PAN)"
|
default y
|
help
|
Privileged Access Never (PAN; part of the ARMv8.1 Extensions)
|
prevents the kernel or hypervisor from accessing user-space (EL0)
|
memory directly.
|
|
Choosing this option will cause any unprotected (not using
|
copy_to_user et al) memory access to fail with a permission fault.
|
|
The feature is detected at runtime, and will remain as a 'nop'
|
instruction if the cpu does not implement the feature.
|
|
config ARM64_LSE_ATOMICS
|
bool "Atomic instructions"
|
default y
|
help
|
As part of the Large System Extensions, ARMv8.1 introduces new
|
atomic instructions that are designed specifically to scale in
|
very large systems.
|
|
Say Y here to make use of these instructions for the in-kernel
|
atomic routines. This incurs a small overhead on CPUs that do
|
not support these instructions and requires the kernel to be
|
built with binutils >= 2.25 in order for the new instructions
|
to be used.
|
|
config ARM64_VHE
|
bool "Enable support for Virtualization Host Extensions (VHE)"
|
default y
|
help
|
Virtualization Host Extensions (VHE) allow the kernel to run
|
directly at EL2 (instead of EL1) on processors that support
|
it. This leads to better performance for KVM, as they reduce
|
the cost of the world switch.
|
|
Selecting this option allows the VHE feature to be detected
|
at runtime, and does not affect processors that do not
|
implement this feature.
|
|
endmenu
|
|
menu "ARMv8.2 architectural features"
|
|
config ARM64_UAO
|
bool "Enable support for User Access Override (UAO)"
|
default y
|
help
|
User Access Override (UAO; part of the ARMv8.2 Extensions)
|
causes the 'unprivileged' variant of the load/store instructions to
|
be overridden to be privileged.
|
|
This option changes get_user() and friends to use the 'unprivileged'
|
variant of the load/store instructions. This ensures that user-space
|
really did have access to the supplied memory. When addr_limit is
|
set to kernel memory the UAO bit will be set, allowing privileged
|
access to kernel memory.
|
|
Choosing this option will cause copy_to_user() et al to use user-space
|
memory permissions.
|
|
The feature is detected at runtime, the kernel will use the
|
regular load/store instructions if the cpu does not implement the
|
feature.
|
|
config ARM64_PMEM
|
bool "Enable support for persistent memory"
|
select ARCH_HAS_PMEM_API
|
select ARCH_HAS_UACCESS_FLUSHCACHE
|
help
|
Say Y to enable support for the persistent memory API based on the
|
ARMv8.2 DCPoP feature.
|
|
The feature is detected at runtime, and the kernel will use DC CVAC
|
operations if DC CVAP is not supported (following the behaviour of
|
DC CVAP itself if the system does not define a point of persistence).
|
|
config ARM64_RAS_EXTN
|
bool "Enable support for RAS CPU Extensions"
|
default y
|
help
|
CPUs that support the Reliability, Availability and Serviceability
|
(RAS) Extensions, part of ARMv8.2 are able to track faults and
|
errors, classify them and report them to software.
|
|
On CPUs with these extensions system software can use additional
|
barriers to determine if faults are pending and read the
|
classification from a new set of registers.
|
|
Selecting this feature will allow the kernel to use these barriers
|
and access the new registers if the system supports the extension.
|
Platform RAS features may additionally depend on firmware support.
|
|
endmenu
|
|
config ARM64_SVE
|
bool "ARM Scalable Vector Extension support"
|
default y
|
depends on !KVM || ARM64_VHE
|
help
|
The Scalable Vector Extension (SVE) is an extension to the AArch64
|
execution state which complements and extends the SIMD functionality
|
of the base architecture to support much larger vectors and to enable
|
additional vectorisation opportunities.
|
|
To enable use of this extension on CPUs that implement it, say Y.
|
|
Note that for architectural reasons, firmware _must_ implement SVE
|
support when running on SVE capable hardware. The required support
|
is present in:
|
|
* version 1.5 and later of the ARM Trusted Firmware
|
* the AArch64 boot wrapper since commit 5e1261e08abf
|
("bootwrapper: SVE: Enable SVE for EL2 and below").
|
|
For other firmware implementations, consult the firmware documentation
|
or vendor.
|
|
If you need the kernel to boot on SVE-capable hardware with broken
|
firmware, you may need to say N here until you get your firmware
|
fixed. Otherwise, you may experience firmware panics or lockups when
|
booting the kernel. If unsure and you are not observing these
|
symptoms, you should assume that it is safe to say Y.
|
|
CPUs that support SVE are architecturally required to support the
|
Virtualization Host Extensions (VHE), so the kernel makes no
|
provision for supporting SVE alongside KVM without VHE enabled.
|
Thus, you will need to enable CONFIG_ARM64_VHE if you want to support
|
KVM in the same kernel image.
|
|
config ARM64_MODULE_PLTS
|
bool
|
select HAVE_MOD_ARCH_SPECIFIC
|
|
config RELOCATABLE
|
bool
|
select ARCH_HAS_RELR
|
help
|
This builds the kernel as a Position Independent Executable (PIE),
|
which retains all relocation metadata required to relocate the
|
kernel binary at runtime to a different virtual address than the
|
address it was linked at.
|
Since AArch64 uses the RELA relocation format, this requires a
|
relocation pass at runtime even if the kernel is loaded at the
|
same address it was linked at.
|
|
config RANDOMIZE_BASE
|
bool "Randomize the address of the kernel image"
|
select ARM64_MODULE_PLTS if MODULES
|
select RELOCATABLE
|
help
|
Randomizes the virtual address at which the kernel image is
|
loaded, as a security feature that deters exploit attempts
|
relying on knowledge of the location of kernel internals.
|
|
It is the bootloader's job to provide entropy, by passing a
|
random u64 value in /chosen/kaslr-seed at kernel entry.
|
|
When booting via the UEFI stub, it will invoke the firmware's
|
EFI_RNG_PROTOCOL implementation (if available) to supply entropy
|
to the kernel proper. In addition, it will randomise the physical
|
location of the kernel Image as well.
|
|
If unsure, say N.
|
|
config RANDOMIZE_MODULE_REGION_FULL
|
bool "Randomize the module region over a 4 GB range"
|
depends on RANDOMIZE_BASE
|
default y
|
help
|
Randomizes the location of the module region inside a 4 GB window
|
covering the core kernel. This way, it is less likely for modules
|
to leak information about the location of core kernel data structures
|
but it does imply that function calls between modules and the core
|
kernel will need to be resolved via veneers in the module PLT.
|
|
When this option is not set, the module region will be randomized over
|
a limited range that contains the [_stext, _etext] interval of the
|
core kernel, so branch relocations are always in range.
|
|
endmenu
|
|
menu "Boot options"
|
|
config ARM64_ACPI_PARKING_PROTOCOL
|
bool "Enable support for the ARM64 ACPI parking protocol"
|
depends on ACPI
|
help
|
Enable support for the ARM64 ACPI parking protocol. If disabled
|
the kernel will not allow booting through the ARM64 ACPI parking
|
protocol even if the corresponding data is present in the ACPI
|
MADT table.
|
|
config CMDLINE
|
string "Default kernel command string"
|
default ""
|
help
|
Provide a set of default command-line options at build time by
|
entering them here. As a minimum, you should specify the the
|
root device (e.g. root=/dev/nfs).
|
|
choice
|
prompt "Kernel command line type" if CMDLINE != ""
|
default CMDLINE_FROM_BOOTLOADER
|
|
config CMDLINE_FROM_BOOTLOADER
|
bool "Use bootloader kernel arguments if available"
|
help
|
Uses the command-line options passed by the boot loader. If
|
the boot loader doesn't provide any, the default kernel command
|
string provided in CMDLINE will be used.
|
|
config CMDLINE_EXTEND
|
bool "Extend bootloader kernel arguments"
|
help
|
The command-line arguments provided by the boot loader will be
|
appended to the default kernel command string.
|
|
config CMDLINE_FORCE
|
bool "Always use the default kernel command string"
|
help
|
Always use the default kernel command string, even if the boot
|
loader passes other arguments to the kernel.
|
This is useful if you cannot or don't want to change the
|
command-line options your boot loader passes to the kernel.
|
endchoice
|
|
config EFI_STUB
|
bool
|
|
config EFI
|
bool "UEFI runtime support"
|
depends on OF && !CPU_BIG_ENDIAN
|
depends on KERNEL_MODE_NEON
|
select ARCH_SUPPORTS_ACPI
|
select LIBFDT
|
select UCS2_STRING
|
select EFI_PARAMS_FROM_FDT
|
select EFI_RUNTIME_WRAPPERS
|
select EFI_STUB
|
select EFI_ARMSTUB
|
default y
|
help
|
This option provides support for runtime services provided
|
by UEFI firmware (such as non-volatile variables, realtime
|
clock, and platform reset). A UEFI stub is also provided to
|
allow the kernel to be booted as an EFI application. This
|
is only useful on systems that have UEFI firmware.
|
|
config DMI
|
bool "Enable support for SMBIOS (DMI) tables"
|
depends on EFI
|
default y
|
help
|
This enables SMBIOS/DMI feature for systems.
|
|
This option is only useful on systems that have UEFI firmware.
|
However, even with this option, the resultant kernel should
|
continue to boot on existing non-UEFI platforms.
|
|
endmenu
|
|
config COMPAT
|
bool "Kernel support for 32-bit EL0"
|
depends on ARM64_4K_PAGES || EXPERT
|
select COMPAT_BINFMT_ELF if BINFMT_ELF
|
select HAVE_UID16
|
select OLD_SIGSUSPEND3
|
select COMPAT_OLD_SIGACTION
|
help
|
This option enables support for a 32-bit EL0 running under a 64-bit
|
kernel at EL1. AArch32-specific components such as system calls,
|
the user helper functions, VFP support and the ptrace interface are
|
handled appropriately by the kernel.
|
|
If you use a page size other than 4KB (i.e, 16KB or 64KB), please be aware
|
that you will only be able to execute AArch32 binaries that were compiled
|
with page size aligned segments.
|
|
If you want to execute 32-bit userspace applications, say Y.
|
|
config KUSER_HELPERS
|
bool "Enable kuser helpers page for 32 bit applications."
|
depends on COMPAT
|
default y
|
help
|
Warning: disabling this option may break 32-bit user programs.
|
|
Provide kuser helpers to compat tasks. The kernel provides
|
helper code to userspace in read only form at a fixed location
|
to allow userspace to be independent of the CPU type fitted to
|
the system. This permits binaries to be run on ARMv4 through
|
to ARMv8 without modification.
|
|
See Documentation/arm/kernel_user_helpers.txt for details.
|
|
However, the fixed address nature of these helpers can be used
|
by ROP (return orientated programming) authors when creating
|
exploits.
|
|
If all of the binaries and libraries which run on your platform
|
are built specifically for your platform, and make no use of
|
these helpers, then you can turn this option off to hinder
|
such exploits. However, in that case, if a binary or library
|
relying on those helpers is run, it will not function correctly.
|
|
Say N here only if you are absolutely certain that you do not
|
need these helpers; otherwise, the safe option is to say Y.
|
|
config SYSVIPC_COMPAT
|
def_bool y
|
depends on COMPAT && SYSVIPC
|
|
menu "Power management options"
|
|
source "kernel/power/Kconfig"
|
|
config ARCH_HIBERNATION_POSSIBLE
|
def_bool y
|
depends on CPU_PM
|
|
config ARCH_HIBERNATION_HEADER
|
def_bool y
|
depends on HIBERNATION
|
|
config ARCH_SUSPEND_POSSIBLE
|
def_bool y
|
|
endmenu
|
|
menu "CPU Power Management"
|
|
source "drivers/cpuidle/Kconfig"
|
|
source "drivers/cpufreq/Kconfig"
|
|
endmenu
|
|
source "drivers/firmware/Kconfig"
|
|
source "drivers/acpi/Kconfig"
|
|
source "arch/arm64/kvm/Kconfig"
|
|
if CRYPTO
|
source "arch/arm64/crypto/Kconfig"
|
endif
|
