3 select ACPI_CCA_REQUIRED if ACPI
4 select ACPI_GENERIC_GSI if ACPI
5 select ACPI_GTDT if ACPI
6 select ACPI_IORT if ACPI
7 select ACPI_REDUCED_HARDWARE_ONLY if ACPI
8 select ACPI_MCFG if ACPI
9 select ACPI_SPCR_TABLE if ACPI
10 select ARCH_CLOCKSOURCE_DATA
11 select ARCH_HAS_DEBUG_VIRTUAL
12 select ARCH_HAS_DEVMEM_IS_ALLOWED
13 select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI
14 select ARCH_HAS_ELF_RANDOMIZE
15 select ARCH_HAS_FORTIFY_SOURCE
16 select ARCH_HAS_GCOV_PROFILE_ALL
17 select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
19 select ARCH_HAS_MEMBARRIER_SYNC_CORE
20 select ARCH_HAS_SET_MEMORY
21 select ARCH_HAS_SG_CHAIN
22 select ARCH_HAS_STRICT_KERNEL_RWX
23 select ARCH_HAS_STRICT_MODULE_RWX
24 select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
25 select ARCH_HAVE_NMI_SAFE_CMPXCHG
26 select ARCH_INLINE_READ_LOCK if !PREEMPT
27 select ARCH_INLINE_READ_LOCK_BH if !PREEMPT
28 select ARCH_INLINE_READ_LOCK_IRQ if !PREEMPT
29 select ARCH_INLINE_READ_LOCK_IRQSAVE if !PREEMPT
30 select ARCH_INLINE_READ_UNLOCK if !PREEMPT
31 select ARCH_INLINE_READ_UNLOCK_BH if !PREEMPT
32 select ARCH_INLINE_READ_UNLOCK_IRQ if !PREEMPT
33 select ARCH_INLINE_READ_UNLOCK_IRQRESTORE if !PREEMPT
34 select ARCH_INLINE_WRITE_LOCK if !PREEMPT
35 select ARCH_INLINE_WRITE_LOCK_BH if !PREEMPT
36 select ARCH_INLINE_WRITE_LOCK_IRQ if !PREEMPT
37 select ARCH_INLINE_WRITE_LOCK_IRQSAVE if !PREEMPT
38 select ARCH_INLINE_WRITE_UNLOCK if !PREEMPT
39 select ARCH_INLINE_WRITE_UNLOCK_BH if !PREEMPT
40 select ARCH_INLINE_WRITE_UNLOCK_IRQ if !PREEMPT
41 select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE if !PREEMPT
42 select ARCH_USE_CMPXCHG_LOCKREF
43 select ARCH_USE_QUEUED_RWLOCKS
44 select ARCH_SUPPORTS_MEMORY_FAILURE
45 select ARCH_SUPPORTS_ATOMIC_RMW
46 select ARCH_SUPPORTS_NUMA_BALANCING
47 select ARCH_WANT_COMPAT_IPC_PARSE_VERSION
48 select ARCH_WANT_FRAME_POINTERS
49 select ARCH_HAS_UBSAN_SANITIZE_ALL
53 select AUDIT_ARCH_COMPAT_GENERIC
54 select ARM_GIC_V2M if PCI
56 select ARM_GIC_V3_ITS if PCI
58 select BUILDTIME_EXTABLE_SORT
59 select CLONE_BACKWARDS
61 select CPU_PM if (SUSPEND || CPU_IDLE)
62 select DCACHE_WORD_ACCESS
66 select GENERIC_ALLOCATOR
67 select GENERIC_ARCH_TOPOLOGY
68 select GENERIC_CLOCKEVENTS
69 select GENERIC_CLOCKEVENTS_BROADCAST
70 select GENERIC_CPU_AUTOPROBE
71 select GENERIC_EARLY_IOREMAP
72 select GENERIC_IDLE_POLL_SETUP
73 select GENERIC_IRQ_PROBE
74 select GENERIC_IRQ_SHOW
75 select GENERIC_IRQ_SHOW_LEVEL
76 select GENERIC_PCI_IOMAP
77 select GENERIC_SCHED_CLOCK
78 select GENERIC_SMP_IDLE_THREAD
79 select GENERIC_STRNCPY_FROM_USER
80 select GENERIC_STRNLEN_USER
81 select GENERIC_TIME_VSYSCALL
82 select HANDLE_DOMAIN_IRQ
83 select HARDIRQS_SW_RESEND
84 select HAVE_ACPI_APEI if (ACPI && EFI)
85 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
86 select HAVE_ARCH_AUDITSYSCALL
87 select HAVE_ARCH_BITREVERSE
88 select HAVE_ARCH_HUGE_VMAP
89 select HAVE_ARCH_JUMP_LABEL
90 select HAVE_ARCH_KASAN if !(ARM64_16K_PAGES && ARM64_VA_BITS_48)
92 select HAVE_ARCH_MMAP_RND_BITS
93 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT
94 select HAVE_ARCH_SECCOMP_FILTER
95 select HAVE_ARCH_THREAD_STRUCT_WHITELIST
96 select HAVE_ARCH_TRACEHOOK
97 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
98 select HAVE_ARCH_VMAP_STACK
101 select HAVE_C_RECORDMCOUNT
102 select HAVE_CC_STACKPROTECTOR
103 select HAVE_CMPXCHG_DOUBLE
104 select HAVE_CMPXCHG_LOCAL
105 select HAVE_CONTEXT_TRACKING
106 select HAVE_DEBUG_BUGVERBOSE
107 select HAVE_DEBUG_KMEMLEAK
108 select HAVE_DMA_API_DEBUG
109 select HAVE_DMA_CONTIGUOUS
110 select HAVE_DYNAMIC_FTRACE
111 select HAVE_EFFICIENT_UNALIGNED_ACCESS
112 select HAVE_FTRACE_MCOUNT_RECORD
113 select HAVE_FUNCTION_TRACER
114 select HAVE_FUNCTION_GRAPH_TRACER
115 select HAVE_GCC_PLUGINS
116 select HAVE_GENERIC_DMA_COHERENT
117 select HAVE_HW_BREAKPOINT if PERF_EVENTS
118 select HAVE_IRQ_TIME_ACCOUNTING
120 select HAVE_MEMBLOCK_NODE_MAP if NUMA
122 select HAVE_PATA_PLATFORM
123 select HAVE_PERF_EVENTS
124 select HAVE_PERF_REGS
125 select HAVE_PERF_USER_STACK_DUMP
126 select HAVE_REGS_AND_STACK_ACCESS_API
127 select HAVE_RCU_TABLE_FREE
128 select HAVE_SYSCALL_TRACEPOINTS
130 select HAVE_KRETPROBES
131 select IOMMU_DMA if IOMMU_SUPPORT
133 select IRQ_FORCED_THREADING
134 select MODULES_USE_ELF_RELA
135 select MULTI_IRQ_HANDLER
138 select OF_EARLY_FLATTREE
139 select OF_RESERVED_MEM
140 select PCI_ECAM if ACPI
145 select SYSCTL_EXCEPTION_TRACE
146 select THREAD_INFO_IN_TASK
148 ARM 64-bit (AArch64) Linux support.
153 config ARCH_PHYS_ADDR_T_64BIT
159 config ARM64_PAGE_SHIFT
161 default 16 if ARM64_64K_PAGES
162 default 14 if ARM64_16K_PAGES
165 config ARM64_CONT_SHIFT
167 default 5 if ARM64_64K_PAGES
168 default 7 if ARM64_16K_PAGES
171 config ARCH_MMAP_RND_BITS_MIN
172 default 14 if ARM64_64K_PAGES
173 default 16 if ARM64_16K_PAGES
176 # max bits determined by the following formula:
177 # VA_BITS - PAGE_SHIFT - 3
178 config ARCH_MMAP_RND_BITS_MAX
179 default 19 if ARM64_VA_BITS=36
180 default 24 if ARM64_VA_BITS=39
181 default 27 if ARM64_VA_BITS=42
182 default 30 if ARM64_VA_BITS=47
183 default 29 if ARM64_VA_BITS=48 && ARM64_64K_PAGES
184 default 31 if ARM64_VA_BITS=48 && ARM64_16K_PAGES
185 default 33 if ARM64_VA_BITS=48
186 default 14 if ARM64_64K_PAGES
187 default 16 if ARM64_16K_PAGES
190 config ARCH_MMAP_RND_COMPAT_BITS_MIN
191 default 7 if ARM64_64K_PAGES
192 default 9 if ARM64_16K_PAGES
195 config ARCH_MMAP_RND_COMPAT_BITS_MAX
201 config STACKTRACE_SUPPORT
204 config ILLEGAL_POINTER_VALUE
206 default 0xdead000000000000
208 config LOCKDEP_SUPPORT
211 config TRACE_IRQFLAGS_SUPPORT
214 config RWSEM_XCHGADD_ALGORITHM
221 config GENERIC_BUG_RELATIVE_POINTERS
223 depends on GENERIC_BUG
225 config GENERIC_HWEIGHT
231 config GENERIC_CALIBRATE_DELAY
237 config HAVE_GENERIC_GUP
240 config ARCH_DMA_ADDR_T_64BIT
243 config NEED_DMA_MAP_STATE
246 config NEED_SG_DMA_LENGTH
258 config KERNEL_MODE_NEON
261 config FIX_EARLYCON_MEM
264 config PGTABLE_LEVELS
266 default 2 if ARM64_16K_PAGES && ARM64_VA_BITS_36
267 default 2 if ARM64_64K_PAGES && ARM64_VA_BITS_42
268 default 3 if ARM64_64K_PAGES && ARM64_VA_BITS_48
269 default 3 if ARM64_4K_PAGES && ARM64_VA_BITS_39
270 default 3 if ARM64_16K_PAGES && ARM64_VA_BITS_47
271 default 4 if !ARM64_64K_PAGES && ARM64_VA_BITS_48
273 config ARCH_SUPPORTS_UPROBES
276 config ARCH_PROC_KCORE_TEXT
279 config MULTI_IRQ_HANDLER
282 source "init/Kconfig"
284 source "kernel/Kconfig.freezer"
286 source "arch/arm64/Kconfig.platforms"
293 This feature enables support for PCI bus system. If you say Y
294 here, the kernel will include drivers and infrastructure code
295 to support PCI bus devices.
300 config PCI_DOMAINS_GENERIC
306 source "drivers/pci/Kconfig"
310 menu "Kernel Features"
312 menu "ARM errata workarounds via the alternatives framework"
314 config ARM64_ERRATUM_826319
315 bool "Cortex-A53: 826319: System might deadlock if a write cannot complete until read data is accepted"
318 This option adds an alternative code sequence to work around ARM
319 erratum 826319 on Cortex-A53 parts up to r0p2 with an AMBA 4 ACE or
320 AXI master interface and an L2 cache.
322 If a Cortex-A53 uses an AMBA AXI4 ACE interface to other processors
323 and is unable to accept a certain write via this interface, it will
324 not progress on read data presented on the read data channel and the
327 The workaround promotes data cache clean instructions to
328 data cache clean-and-invalidate.
329 Please note that this does not necessarily enable the workaround,
330 as it depends on the alternative framework, which will only patch
331 the kernel if an affected CPU is detected.
335 config ARM64_ERRATUM_827319
336 bool "Cortex-A53: 827319: Data cache clean instructions might cause overlapping transactions to the interconnect"
339 This option adds an alternative code sequence to work around ARM
340 erratum 827319 on Cortex-A53 parts up to r0p2 with an AMBA 5 CHI
341 master interface and an L2 cache.
343 Under certain conditions this erratum can cause a clean line eviction
344 to occur at the same time as another transaction to the same address
345 on the AMBA 5 CHI interface, which can cause data corruption if the
346 interconnect reorders the two transactions.
348 The workaround promotes data cache clean instructions to
349 data cache clean-and-invalidate.
350 Please note that this does not necessarily enable the workaround,
351 as it depends on the alternative framework, which will only patch
352 the kernel if an affected CPU is detected.
356 config ARM64_ERRATUM_824069
357 bool "Cortex-A53: 824069: Cache line might not be marked as clean after a CleanShared snoop"
360 This option adds an alternative code sequence to work around ARM
361 erratum 824069 on Cortex-A53 parts up to r0p2 when it is connected
362 to a coherent interconnect.
364 If a Cortex-A53 processor is executing a store or prefetch for
365 write instruction at the same time as a processor in another
366 cluster is executing a cache maintenance operation to the same
367 address, then this erratum might cause a clean cache line to be
368 incorrectly marked as dirty.
370 The workaround promotes data cache clean instructions to
371 data cache clean-and-invalidate.
372 Please note that this option does not necessarily enable the
373 workaround, as it depends on the alternative framework, which will
374 only patch the kernel if an affected CPU is detected.
378 config ARM64_ERRATUM_819472
379 bool "Cortex-A53: 819472: Store exclusive instructions might cause data corruption"
382 This option adds an alternative code sequence to work around ARM
383 erratum 819472 on Cortex-A53 parts up to r0p1 with an L2 cache
384 present when it is connected to a coherent interconnect.
386 If the processor is executing a load and store exclusive sequence at
387 the same time as a processor in another cluster is executing a cache
388 maintenance operation to the same address, then this erratum might
389 cause data corruption.
391 The workaround promotes data cache clean instructions to
392 data cache clean-and-invalidate.
393 Please note that this does not necessarily enable the workaround,
394 as it depends on the alternative framework, which will only patch
395 the kernel if an affected CPU is detected.
399 config ARM64_ERRATUM_832075
400 bool "Cortex-A57: 832075: possible deadlock on mixing exclusive memory accesses with device loads"
403 This option adds an alternative code sequence to work around ARM
404 erratum 832075 on Cortex-A57 parts up to r1p2.
406 Affected Cortex-A57 parts might deadlock when exclusive load/store
407 instructions to Write-Back memory are mixed with Device loads.
409 The workaround is to promote device loads to use Load-Acquire
411 Please note that this does not necessarily enable the workaround,
412 as it depends on the alternative framework, which will only patch
413 the kernel if an affected CPU is detected.
417 config ARM64_ERRATUM_834220
418 bool "Cortex-A57: 834220: Stage 2 translation fault might be incorrectly reported in presence of a Stage 1 fault"
422 This option adds an alternative code sequence to work around ARM
423 erratum 834220 on Cortex-A57 parts up to r1p2.
425 Affected Cortex-A57 parts might report a Stage 2 translation
426 fault as the result of a Stage 1 fault for load crossing a
427 page boundary when there is a permission or device memory
428 alignment fault at Stage 1 and a translation fault at Stage 2.
430 The workaround is to verify that the Stage 1 translation
431 doesn't generate a fault before handling the Stage 2 fault.
432 Please note that this does not necessarily enable the workaround,
433 as it depends on the alternative framework, which will only patch
434 the kernel if an affected CPU is detected.
438 config ARM64_ERRATUM_845719
439 bool "Cortex-A53: 845719: a load might read incorrect data"
443 This option adds an alternative code sequence to work around ARM
444 erratum 845719 on Cortex-A53 parts up to r0p4.
446 When running a compat (AArch32) userspace on an affected Cortex-A53
447 part, a load at EL0 from a virtual address that matches the bottom 32
448 bits of the virtual address used by a recent load at (AArch64) EL1
449 might return incorrect data.
451 The workaround is to write the contextidr_el1 register on exception
452 return to a 32-bit task.
453 Please note that this does not necessarily enable the workaround,
454 as it depends on the alternative framework, which will only patch
455 the kernel if an affected CPU is detected.
459 config ARM64_ERRATUM_843419
460 bool "Cortex-A53: 843419: A load or store might access an incorrect address"
462 select ARM64_MODULE_PLTS if MODULES
464 This option links the kernel with '--fix-cortex-a53-843419' and
465 enables PLT support to replace certain ADRP instructions, which can
466 cause subsequent memory accesses to use an incorrect address on
467 Cortex-A53 parts up to r0p4.
471 config ARM64_ERRATUM_1024718
472 bool "Cortex-A55: 1024718: Update of DBM/AP bits without break before make might result in incorrect update"
475 This option adds work around for Arm Cortex-A55 Erratum 1024718.
477 Affected Cortex-A55 cores (r0p0, r0p1, r1p0) could cause incorrect
478 update of the hardware dirty bit when the DBM/AP bits are updated
479 without a break-before-make. The work around is to disable the usage
480 of hardware DBM locally on the affected cores. CPUs not affected by
481 erratum will continue to use the feature.
485 config CAVIUM_ERRATUM_22375
486 bool "Cavium erratum 22375, 24313"
489 Enable workaround for erratum 22375, 24313.
491 This implements two gicv3-its errata workarounds for ThunderX. Both
492 with small impact affecting only ITS table allocation.
494 erratum 22375: only alloc 8MB table size
495 erratum 24313: ignore memory access type
497 The fixes are in ITS initialization and basically ignore memory access
498 type and table size provided by the TYPER and BASER registers.
502 config CAVIUM_ERRATUM_23144
503 bool "Cavium erratum 23144: ITS SYNC hang on dual socket system"
507 ITS SYNC command hang for cross node io and collections/cpu mapping.
511 config CAVIUM_ERRATUM_23154
512 bool "Cavium erratum 23154: Access to ICC_IAR1_EL1 is not sync'ed"
515 The gicv3 of ThunderX requires a modified version for
516 reading the IAR status to ensure data synchronization
517 (access to icc_iar1_el1 is not sync'ed before and after).
521 config CAVIUM_ERRATUM_27456
522 bool "Cavium erratum 27456: Broadcast TLBI instructions may cause icache corruption"
525 On ThunderX T88 pass 1.x through 2.1 parts, broadcast TLBI
526 instructions may cause the icache to become corrupted if it
527 contains data for a non-current ASID. The fix is to
528 invalidate the icache when changing the mm context.
532 config CAVIUM_ERRATUM_30115
533 bool "Cavium erratum 30115: Guest may disable interrupts in host"
536 On ThunderX T88 pass 1.x through 2.2, T81 pass 1.0 through
537 1.2, and T83 Pass 1.0, KVM guest execution may disable
538 interrupts in host. Trapping both GICv3 group-0 and group-1
539 accesses sidesteps the issue.
543 config QCOM_FALKOR_ERRATUM_1003
544 bool "Falkor E1003: Incorrect translation due to ASID change"
547 On Falkor v1, an incorrect ASID may be cached in the TLB when ASID
548 and BADDR are changed together in TTBRx_EL1. Since we keep the ASID
549 in TTBR1_EL1, this situation only occurs in the entry trampoline and
550 then only for entries in the walk cache, since the leaf translation
551 is unchanged. Work around the erratum by invalidating the walk cache
552 entries for the trampoline before entering the kernel proper.
554 config QCOM_FALKOR_ERRATUM_1009
555 bool "Falkor E1009: Prematurely complete a DSB after a TLBI"
558 On Falkor v1, the CPU may prematurely complete a DSB following a
559 TLBI xxIS invalidate maintenance operation. Repeat the TLBI operation
560 one more time to fix the issue.
564 config QCOM_QDF2400_ERRATUM_0065
565 bool "QDF2400 E0065: Incorrect GITS_TYPER.ITT_Entry_size"
568 On Qualcomm Datacenter Technologies QDF2400 SoC, ITS hardware reports
569 ITE size incorrectly. The GITS_TYPER.ITT_Entry_size field should have
570 been indicated as 16Bytes (0xf), not 8Bytes (0x7).
574 config SOCIONEXT_SYNQUACER_PREITS
575 bool "Socionext Synquacer: Workaround for GICv3 pre-ITS"
578 Socionext Synquacer SoCs implement a separate h/w block to generate
579 MSI doorbell writes with non-zero values for the device ID.
583 config HISILICON_ERRATUM_161600802
584 bool "Hip07 161600802: Erroneous redistributor VLPI base"
587 The HiSilicon Hip07 SoC usees the wrong redistributor base
588 when issued ITS commands such as VMOVP and VMAPP, and requires
589 a 128kB offset to be applied to the target address in this commands.
593 config QCOM_FALKOR_ERRATUM_E1041
594 bool "Falkor E1041: Speculative instruction fetches might cause errant memory access"
597 Falkor CPU may speculatively fetch instructions from an improper
598 memory location when MMU translation is changed from SCTLR_ELn[M]=1
599 to SCTLR_ELn[M]=0. Prefix an ISB instruction to fix the problem.
608 default ARM64_4K_PAGES
610 Page size (translation granule) configuration.
612 config ARM64_4K_PAGES
615 This feature enables 4KB pages support.
617 config ARM64_16K_PAGES
620 The system will use 16KB pages support. AArch32 emulation
621 requires applications compiled with 16K (or a multiple of 16K)
624 config ARM64_64K_PAGES
627 This feature enables 64KB pages support (4KB by default)
628 allowing only two levels of page tables and faster TLB
629 look-up. AArch32 emulation requires applications compiled
630 with 64K aligned segments.
635 prompt "Virtual address space size"
636 default ARM64_VA_BITS_39 if ARM64_4K_PAGES
637 default ARM64_VA_BITS_47 if ARM64_16K_PAGES
638 default ARM64_VA_BITS_42 if ARM64_64K_PAGES
640 Allows choosing one of multiple possible virtual address
641 space sizes. The level of translation table is determined by
642 a combination of page size and virtual address space size.
644 config ARM64_VA_BITS_36
645 bool "36-bit" if EXPERT
646 depends on ARM64_16K_PAGES
648 config ARM64_VA_BITS_39
650 depends on ARM64_4K_PAGES
652 config ARM64_VA_BITS_42
654 depends on ARM64_64K_PAGES
656 config ARM64_VA_BITS_47
658 depends on ARM64_16K_PAGES
660 config ARM64_VA_BITS_48
667 default 36 if ARM64_VA_BITS_36
668 default 39 if ARM64_VA_BITS_39
669 default 42 if ARM64_VA_BITS_42
670 default 47 if ARM64_VA_BITS_47
671 default 48 if ARM64_VA_BITS_48
674 prompt "Physical address space size"
675 default ARM64_PA_BITS_48
677 Choose the maximum physical address range that the kernel will
680 config ARM64_PA_BITS_48
683 config ARM64_PA_BITS_52
684 bool "52-bit (ARMv8.2)"
685 depends on ARM64_64K_PAGES
686 depends on ARM64_PAN || !ARM64_SW_TTBR0_PAN
688 Enable support for a 52-bit physical address space, introduced as
689 part of the ARMv8.2-LPA extension.
691 With this enabled, the kernel will also continue to work on CPUs that
692 do not support ARMv8.2-LPA, but with some added memory overhead (and
693 minor performance overhead).
699 default 48 if ARM64_PA_BITS_48
700 default 52 if ARM64_PA_BITS_52
702 config CPU_BIG_ENDIAN
703 bool "Build big-endian kernel"
705 Say Y if you plan on running a kernel in big-endian mode.
708 bool "Multi-core scheduler support"
710 Multi-core scheduler support improves the CPU scheduler's decision
711 making when dealing with multi-core CPU chips at a cost of slightly
712 increased overhead in some places. If unsure say N here.
715 bool "SMT scheduler support"
717 Improves the CPU scheduler's decision making when dealing with
718 MultiThreading at a cost of slightly increased overhead in some
719 places. If unsure say N here.
722 int "Maximum number of CPUs (2-4096)"
724 # These have to remain sorted largest to smallest
728 bool "Support for hot-pluggable CPUs"
729 select GENERIC_IRQ_MIGRATION
731 Say Y here to experiment with turning CPUs off and on. CPUs
732 can be controlled through /sys/devices/system/cpu.
734 # Common NUMA Features
736 bool "Numa Memory Allocation and Scheduler Support"
737 select ACPI_NUMA if ACPI
740 Enable NUMA (Non Uniform Memory Access) support.
742 The kernel will try to allocate memory used by a CPU on the
743 local memory of the CPU and add some more
744 NUMA awareness to the kernel.
747 int "Maximum NUMA Nodes (as a power of 2)"
750 depends on NEED_MULTIPLE_NODES
752 Specify the maximum number of NUMA Nodes available on the target
753 system. Increases memory reserved to accommodate various tables.
755 config USE_PERCPU_NUMA_NODE_ID
759 config HAVE_SETUP_PER_CPU_AREA
763 config NEED_PER_CPU_EMBED_FIRST_CHUNK
771 source kernel/Kconfig.preempt
772 source kernel/Kconfig.hz
774 config ARCH_SUPPORTS_DEBUG_PAGEALLOC
777 config ARCH_HAS_HOLES_MEMORYMODEL
778 def_bool y if SPARSEMEM
780 config ARCH_SPARSEMEM_ENABLE
782 select SPARSEMEM_VMEMMAP_ENABLE
784 config ARCH_SPARSEMEM_DEFAULT
785 def_bool ARCH_SPARSEMEM_ENABLE
787 config ARCH_SELECT_MEMORY_MODEL
788 def_bool ARCH_SPARSEMEM_ENABLE
790 config HAVE_ARCH_PFN_VALID
791 def_bool ARCH_HAS_HOLES_MEMORYMODEL || !SPARSEMEM
793 config HW_PERF_EVENTS
797 config SYS_SUPPORTS_HUGETLBFS
800 config ARCH_WANT_HUGE_PMD_SHARE
801 def_bool y if ARM64_4K_PAGES || (ARM64_16K_PAGES && !ARM64_VA_BITS_36)
803 config ARCH_HAS_CACHE_LINE_SIZE
809 bool "Enable seccomp to safely compute untrusted bytecode"
811 This kernel feature is useful for number crunching applications
812 that may need to compute untrusted bytecode during their
813 execution. By using pipes or other transports made available to
814 the process as file descriptors supporting the read/write
815 syscalls, it's possible to isolate those applications in
816 their own address space using seccomp. Once seccomp is
817 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
818 and the task is only allowed to execute a few safe syscalls
819 defined by each seccomp mode.
822 bool "Enable paravirtualization code"
824 This changes the kernel so it can modify itself when it is run
825 under a hypervisor, potentially improving performance significantly
826 over full virtualization.
828 config PARAVIRT_TIME_ACCOUNTING
829 bool "Paravirtual steal time accounting"
833 Select this option to enable fine granularity task steal time
834 accounting. Time spent executing other tasks in parallel with
835 the current vCPU is discounted from the vCPU power. To account for
836 that, there can be a small performance impact.
838 If in doubt, say N here.
841 depends on PM_SLEEP_SMP
843 bool "kexec system call"
845 kexec is a system call that implements the ability to shutdown your
846 current kernel, and to start another kernel. It is like a reboot
847 but it is independent of the system firmware. And like a reboot
848 you can start any kernel with it, not just Linux.
851 bool "Build kdump crash kernel"
853 Generate crash dump after being started by kexec. This should
854 be normally only set in special crash dump kernels which are
855 loaded in the main kernel with kexec-tools into a specially
856 reserved region and then later executed after a crash by
859 For more details see Documentation/kdump/kdump.txt
866 bool "Xen guest support on ARM64"
867 depends on ARM64 && OF
871 Say Y if you want to run Linux in a Virtual Machine on Xen on ARM64.
873 config FORCE_MAX_ZONEORDER
875 default "14" if (ARM64_64K_PAGES && TRANSPARENT_HUGEPAGE)
876 default "12" if (ARM64_16K_PAGES && TRANSPARENT_HUGEPAGE)
879 The kernel memory allocator divides physically contiguous memory
880 blocks into "zones", where each zone is a power of two number of
881 pages. This option selects the largest power of two that the kernel
882 keeps in the memory allocator. If you need to allocate very large
883 blocks of physically contiguous memory, then you may need to
886 This config option is actually maximum order plus one. For example,
887 a value of 11 means that the largest free memory block is 2^10 pages.
889 We make sure that we can allocate upto a HugePage size for each configuration.
891 MAX_ORDER = (PMD_SHIFT - PAGE_SHIFT) + 1 => PAGE_SHIFT - 2
893 However for 4K, we choose a higher default value, 11 as opposed to 10, giving us
894 4M allocations matching the default size used by generic code.
896 config UNMAP_KERNEL_AT_EL0
897 bool "Unmap kernel when running in userspace (aka \"KAISER\")" if EXPERT
900 Speculation attacks against some high-performance processors can
901 be used to bypass MMU permission checks and leak kernel data to
902 userspace. This can be defended against by unmapping the kernel
903 when running in userspace, mapping it back in on exception entry
904 via a trampoline page in the vector table.
908 config HARDEN_BRANCH_PREDICTOR
909 bool "Harden the branch predictor against aliasing attacks" if EXPERT
912 Speculation attacks against some high-performance processors rely on
913 being able to manipulate the branch predictor for a victim context by
914 executing aliasing branches in the attacker context. Such attacks
915 can be partially mitigated against by clearing internal branch
916 predictor state and limiting the prediction logic in some situations.
918 This config option will take CPU-specific actions to harden the
919 branch predictor against aliasing attacks and may rely on specific
920 instruction sequences or control bits being set by the system
925 config HARDEN_EL2_VECTORS
926 bool "Harden EL2 vector mapping against system register leak" if EXPERT
929 Speculation attacks against some high-performance processors can
930 be used to leak privileged information such as the vector base
931 register, resulting in a potential defeat of the EL2 layout
934 This config option will map the vectors to a fixed location,
935 independent of the EL2 code mapping, so that revealing VBAR_EL2
936 to an attacker does not give away any extra information. This
937 only gets enabled on affected CPUs.
941 menuconfig ARMV8_DEPRECATED
942 bool "Emulate deprecated/obsolete ARMv8 instructions"
946 Legacy software support may require certain instructions
947 that have been deprecated or obsoleted in the architecture.
949 Enable this config to enable selective emulation of these
957 bool "Emulate SWP/SWPB instructions"
959 ARMv8 obsoletes the use of A32 SWP/SWPB instructions such that
960 they are always undefined. Say Y here to enable software
961 emulation of these instructions for userspace using LDXR/STXR.
963 In some older versions of glibc [<=2.8] SWP is used during futex
964 trylock() operations with the assumption that the code will not
965 be preempted. This invalid assumption may be more likely to fail
966 with SWP emulation enabled, leading to deadlock of the user
969 NOTE: when accessing uncached shared regions, LDXR/STXR rely
970 on an external transaction monitoring block called a global
971 monitor to maintain update atomicity. If your system does not
972 implement a global monitor, this option can cause programs that
973 perform SWP operations to uncached memory to deadlock.
977 config CP15_BARRIER_EMULATION
978 bool "Emulate CP15 Barrier instructions"
980 The CP15 barrier instructions - CP15ISB, CP15DSB, and
981 CP15DMB - are deprecated in ARMv8 (and ARMv7). It is
982 strongly recommended to use the ISB, DSB, and DMB
983 instructions instead.
985 Say Y here to enable software emulation of these
986 instructions for AArch32 userspace code. When this option is
987 enabled, CP15 barrier usage is traced which can help
988 identify software that needs updating.
992 config SETEND_EMULATION
993 bool "Emulate SETEND instruction"
995 The SETEND instruction alters the data-endianness of the
996 AArch32 EL0, and is deprecated in ARMv8.
998 Say Y here to enable software emulation of the instruction
999 for AArch32 userspace code.
1001 Note: All the cpus on the system must have mixed endian support at EL0
1002 for this feature to be enabled. If a new CPU - which doesn't support mixed
1003 endian - is hotplugged in after this feature has been enabled, there could
1004 be unexpected results in the applications.
1009 config ARM64_SW_TTBR0_PAN
1010 bool "Emulate Privileged Access Never using TTBR0_EL1 switching"
1012 Enabling this option prevents the kernel from accessing
1013 user-space memory directly by pointing TTBR0_EL1 to a reserved
1014 zeroed area and reserved ASID. The user access routines
1015 restore the valid TTBR0_EL1 temporarily.
1017 menu "ARMv8.1 architectural features"
1019 config ARM64_HW_AFDBM
1020 bool "Support for hardware updates of the Access and Dirty page flags"
1023 The ARMv8.1 architecture extensions introduce support for
1024 hardware updates of the access and dirty information in page
1025 table entries. When enabled in TCR_EL1 (HA and HD bits) on
1026 capable processors, accesses to pages with PTE_AF cleared will
1027 set this bit instead of raising an access flag fault.
1028 Similarly, writes to read-only pages with the DBM bit set will
1029 clear the read-only bit (AP[2]) instead of raising a
1032 Kernels built with this configuration option enabled continue
1033 to work on pre-ARMv8.1 hardware and the performance impact is
1034 minimal. If unsure, say Y.
1037 bool "Enable support for Privileged Access Never (PAN)"
1040 Privileged Access Never (PAN; part of the ARMv8.1 Extensions)
1041 prevents the kernel or hypervisor from accessing user-space (EL0)
1044 Choosing this option will cause any unprotected (not using
1045 copy_to_user et al) memory access to fail with a permission fault.
1047 The feature is detected at runtime, and will remain as a 'nop'
1048 instruction if the cpu does not implement the feature.
1050 config ARM64_LSE_ATOMICS
1051 bool "Atomic instructions"
1053 As part of the Large System Extensions, ARMv8.1 introduces new
1054 atomic instructions that are designed specifically to scale in
1057 Say Y here to make use of these instructions for the in-kernel
1058 atomic routines. This incurs a small overhead on CPUs that do
1059 not support these instructions and requires the kernel to be
1060 built with binutils >= 2.25.
1063 bool "Enable support for Virtualization Host Extensions (VHE)"
1066 Virtualization Host Extensions (VHE) allow the kernel to run
1067 directly at EL2 (instead of EL1) on processors that support
1068 it. This leads to better performance for KVM, as they reduce
1069 the cost of the world switch.
1071 Selecting this option allows the VHE feature to be detected
1072 at runtime, and does not affect processors that do not
1073 implement this feature.
1077 menu "ARMv8.2 architectural features"
1080 bool "Enable support for User Access Override (UAO)"
1083 User Access Override (UAO; part of the ARMv8.2 Extensions)
1084 causes the 'unprivileged' variant of the load/store instructions to
1085 be overridden to be privileged.
1087 This option changes get_user() and friends to use the 'unprivileged'
1088 variant of the load/store instructions. This ensures that user-space
1089 really did have access to the supplied memory. When addr_limit is
1090 set to kernel memory the UAO bit will be set, allowing privileged
1091 access to kernel memory.
1093 Choosing this option will cause copy_to_user() et al to use user-space
1096 The feature is detected at runtime, the kernel will use the
1097 regular load/store instructions if the cpu does not implement the
1101 bool "Enable support for persistent memory"
1102 select ARCH_HAS_PMEM_API
1103 select ARCH_HAS_UACCESS_FLUSHCACHE
1105 Say Y to enable support for the persistent memory API based on the
1106 ARMv8.2 DCPoP feature.
1108 The feature is detected at runtime, and the kernel will use DC CVAC
1109 operations if DC CVAP is not supported (following the behaviour of
1110 DC CVAP itself if the system does not define a point of persistence).
1112 config ARM64_RAS_EXTN
1113 bool "Enable support for RAS CPU Extensions"
1116 CPUs that support the Reliability, Availability and Serviceability
1117 (RAS) Extensions, part of ARMv8.2 are able to track faults and
1118 errors, classify them and report them to software.
1120 On CPUs with these extensions system software can use additional
1121 barriers to determine if faults are pending and read the
1122 classification from a new set of registers.
1124 Selecting this feature will allow the kernel to use these barriers
1125 and access the new registers if the system supports the extension.
1126 Platform RAS features may additionally depend on firmware support.
1131 bool "ARM Scalable Vector Extension support"
1134 The Scalable Vector Extension (SVE) is an extension to the AArch64
1135 execution state which complements and extends the SIMD functionality
1136 of the base architecture to support much larger vectors and to enable
1137 additional vectorisation opportunities.
1139 To enable use of this extension on CPUs that implement it, say Y.
1141 Note that for architectural reasons, firmware _must_ implement SVE
1142 support when running on SVE capable hardware. The required support
1145 * version 1.5 and later of the ARM Trusted Firmware
1146 * the AArch64 boot wrapper since commit 5e1261e08abf
1147 ("bootwrapper: SVE: Enable SVE for EL2 and below").
1149 For other firmware implementations, consult the firmware documentation
1152 If you need the kernel to boot on SVE-capable hardware with broken
1153 firmware, you may need to say N here until you get your firmware
1154 fixed. Otherwise, you may experience firmware panics or lockups when
1155 booting the kernel. If unsure and you are not observing these
1156 symptoms, you should assume that it is safe to say Y.
1158 config ARM64_MODULE_PLTS
1160 select HAVE_MOD_ARCH_SPECIFIC
1165 This builds the kernel as a Position Independent Executable (PIE),
1166 which retains all relocation metadata required to relocate the
1167 kernel binary at runtime to a different virtual address than the
1168 address it was linked at.
1169 Since AArch64 uses the RELA relocation format, this requires a
1170 relocation pass at runtime even if the kernel is loaded at the
1171 same address it was linked at.
1173 config RANDOMIZE_BASE
1174 bool "Randomize the address of the kernel image"
1175 select ARM64_MODULE_PLTS if MODULES
1178 Randomizes the virtual address at which the kernel image is
1179 loaded, as a security feature that deters exploit attempts
1180 relying on knowledge of the location of kernel internals.
1182 It is the bootloader's job to provide entropy, by passing a
1183 random u64 value in /chosen/kaslr-seed at kernel entry.
1185 When booting via the UEFI stub, it will invoke the firmware's
1186 EFI_RNG_PROTOCOL implementation (if available) to supply entropy
1187 to the kernel proper. In addition, it will randomise the physical
1188 location of the kernel Image as well.
1192 config RANDOMIZE_MODULE_REGION_FULL
1193 bool "Randomize the module region over a 4 GB range"
1194 depends on RANDOMIZE_BASE
1197 Randomizes the location of the module region inside a 4 GB window
1198 covering the core kernel. This way, it is less likely for modules
1199 to leak information about the location of core kernel data structures
1200 but it does imply that function calls between modules and the core
1201 kernel will need to be resolved via veneers in the module PLT.
1203 When this option is not set, the module region will be randomized over
1204 a limited range that contains the [_stext, _etext] interval of the
1205 core kernel, so branch relocations are always in range.
1211 config ARM64_ACPI_PARKING_PROTOCOL
1212 bool "Enable support for the ARM64 ACPI parking protocol"
1215 Enable support for the ARM64 ACPI parking protocol. If disabled
1216 the kernel will not allow booting through the ARM64 ACPI parking
1217 protocol even if the corresponding data is present in the ACPI
1221 string "Default kernel command string"
1224 Provide a set of default command-line options at build time by
1225 entering them here. As a minimum, you should specify the the
1226 root device (e.g. root=/dev/nfs).
1228 config CMDLINE_FORCE
1229 bool "Always use the default kernel command string"
1231 Always use the default kernel command string, even if the boot
1232 loader passes other arguments to the kernel.
1233 This is useful if you cannot or don't want to change the
1234 command-line options your boot loader passes to the kernel.
1240 bool "UEFI runtime support"
1241 depends on OF && !CPU_BIG_ENDIAN
1242 depends on KERNEL_MODE_NEON
1245 select EFI_PARAMS_FROM_FDT
1246 select EFI_RUNTIME_WRAPPERS
1251 This option provides support for runtime services provided
1252 by UEFI firmware (such as non-volatile variables, realtime
1253 clock, and platform reset). A UEFI stub is also provided to
1254 allow the kernel to be booted as an EFI application. This
1255 is only useful on systems that have UEFI firmware.
1258 bool "Enable support for SMBIOS (DMI) tables"
1262 This enables SMBIOS/DMI feature for systems.
1264 This option is only useful on systems that have UEFI firmware.
1265 However, even with this option, the resultant kernel should
1266 continue to boot on existing non-UEFI platforms.
1270 menu "Userspace binary formats"
1272 source "fs/Kconfig.binfmt"
1275 bool "Kernel support for 32-bit EL0"
1276 depends on ARM64_4K_PAGES || EXPERT
1277 select COMPAT_BINFMT_ELF if BINFMT_ELF
1279 select OLD_SIGSUSPEND3
1280 select COMPAT_OLD_SIGACTION
1282 This option enables support for a 32-bit EL0 running under a 64-bit
1283 kernel at EL1. AArch32-specific components such as system calls,
1284 the user helper functions, VFP support and the ptrace interface are
1285 handled appropriately by the kernel.
1287 If you use a page size other than 4KB (i.e, 16KB or 64KB), please be aware
1288 that you will only be able to execute AArch32 binaries that were compiled
1289 with page size aligned segments.
1291 If you want to execute 32-bit userspace applications, say Y.
1293 config SYSVIPC_COMPAT
1295 depends on COMPAT && SYSVIPC
1299 menu "Power management options"
1301 source "kernel/power/Kconfig"
1303 config ARCH_HIBERNATION_POSSIBLE
1307 config ARCH_HIBERNATION_HEADER
1309 depends on HIBERNATION
1311 config ARCH_SUSPEND_POSSIBLE
1316 menu "CPU Power Management"
1318 source "drivers/cpuidle/Kconfig"
1320 source "drivers/cpufreq/Kconfig"
1324 source "net/Kconfig"
1326 source "drivers/Kconfig"
1328 source "drivers/firmware/Kconfig"
1330 source "drivers/acpi/Kconfig"
1334 source "arch/arm64/kvm/Kconfig"
1336 source "arch/arm64/Kconfig.debug"
1338 source "security/Kconfig"
1340 source "crypto/Kconfig"
1342 source "arch/arm64/crypto/Kconfig"
1345 source "lib/Kconfig"