blob: a1ed5985232c2dc2351d2107b8aa55076d2e4748 [file] [log] [blame]
rjw1f884582022-01-06 17:20:42 +08001config ARM64
2 def_bool y
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
18 select ARCH_HAS_KCOV
19 select ARCH_HAS_SET_MEMORY
20 select ARCH_HAS_SG_CHAIN
21 select ARCH_HAS_STRICT_KERNEL_RWX
22 select ARCH_HAS_STRICT_MODULE_RWX
23 select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
24 select ARCH_HAVE_NMI_SAFE_CMPXCHG if ACPI_APEI_SEA
25 select ARCH_USE_CMPXCHG_LOCKREF
26 select ARCH_SUPPORTS_MEMORY_FAILURE
27 select ARCH_SUPPORTS_LTO_CLANG
28 select ARCH_SUPPORTS_ATOMIC_RMW
29 select ARCH_SUPPORTS_NUMA_BALANCING
30 select ARCH_WANT_COMPAT_IPC_PARSE_VERSION
31 select ARCH_WANT_FRAME_POINTERS
32 select ARCH_HAS_UBSAN_SANITIZE_ALL
33 select ARM_AMBA
34 select ARM_ARCH_TIMER
35 select ARM_GIC
36 select AUDIT_ARCH_COMPAT_GENERIC
37 select ARM_GIC_V2M if PCI
38 select ARM_GIC_V3
39 select ARM_GIC_V3_ITS if PCI
40 select ARM_PSCI_FW
41 select BUILDTIME_EXTABLE_SORT
42 select CLONE_BACKWARDS
43 select COMMON_CLK
44 select CPU_PM if (SUSPEND || CPU_IDLE)
45 select DCACHE_WORD_ACCESS
46 select EDAC_SUPPORT
47 select FRAME_POINTER
48 select GENERIC_ALLOCATOR
49 select GENERIC_ARCH_TOPOLOGY
50 select GENERIC_CLOCKEVENTS
51 select GENERIC_CLOCKEVENTS_BROADCAST
52 select GENERIC_CPU_AUTOPROBE
53 select GENERIC_CPU_VULNERABILITIES
54 select GENERIC_EARLY_IOREMAP
55 select GENERIC_IDLE_POLL_SETUP
56 select GENERIC_IRQ_PROBE
57 select GENERIC_IRQ_SHOW
58 select GENERIC_IRQ_SHOW_LEVEL
59 select GENERIC_PCI_IOMAP
60 select GENERIC_SCHED_CLOCK
61 select GENERIC_SMP_IDLE_THREAD
62 select GENERIC_STRNCPY_FROM_USER
63 select GENERIC_STRNLEN_USER
64 select GENERIC_TIME_VSYSCALL
65 select HANDLE_DOMAIN_IRQ
66 select HARDIRQS_SW_RESEND
67 select HAVE_ACPI_APEI if (ACPI && EFI)
68 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
69 select HAVE_ARCH_AUDITSYSCALL
70 select HAVE_ARCH_BITREVERSE
71 select HAVE_ARCH_HUGE_VMAP
72 select HAVE_ARCH_JUMP_LABEL
73 select HAVE_ARCH_KASAN if SPARSEMEM_VMEMMAP && !(ARM64_16K_PAGES && ARM64_VA_BITS_48)
74 select HAVE_ARCH_KGDB
75 select HAVE_ARCH_MMAP_RND_BITS
76 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT
77 select HAVE_ARCH_SECCOMP_FILTER
78 select HAVE_ARCH_TRACEHOOK
79 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
80 select HAVE_ARCH_VMAP_STACK
81 select HAVE_ARM_SMCCC
82 select HAVE_EBPF_JIT
83 select HAVE_C_RECORDMCOUNT
84 select HAVE_CC_STACKPROTECTOR
85 select HAVE_CMPXCHG_DOUBLE
86 select HAVE_CMPXCHG_LOCAL
87 select HAVE_CONTEXT_TRACKING
88 select HAVE_DEBUG_BUGVERBOSE
89 select HAVE_DEBUG_KMEMLEAK
90 select HAVE_DMA_API_DEBUG
91 select HAVE_DMA_CONTIGUOUS
92 select HAVE_DYNAMIC_FTRACE
93 select HAVE_EFFICIENT_UNALIGNED_ACCESS
94 select HAVE_FTRACE_MCOUNT_RECORD
95 select HAVE_FUNCTION_TRACER
96 select HAVE_FUNCTION_GRAPH_TRACER
97 select HAVE_GCC_PLUGINS
98 select HAVE_GENERIC_DMA_COHERENT
99 select HAVE_HW_BREAKPOINT if PERF_EVENTS
100 select HAVE_IRQ_TIME_ACCOUNTING
101 select HAVE_MEMBLOCK
102 select HAVE_MEMBLOCK_NODE_MAP if NUMA
103 select HAVE_NMI if ACPI_APEI_SEA
104 select HAVE_PATA_PLATFORM
105 select HAVE_PERF_EVENTS
106 select HAVE_PERF_REGS
107 select HAVE_PERF_USER_STACK_DUMP
108 select HAVE_REGS_AND_STACK_ACCESS_API
109 select HAVE_RCU_TABLE_FREE
110 select HAVE_SYSCALL_TRACEPOINTS
111 select HAVE_KPROBES
112 select HAVE_KRETPROBES
113 select IOMMU_DMA if IOMMU_SUPPORT
114 select IRQ_DOMAIN
115 select IRQ_FORCED_THREADING
116 select MODULES_USE_ELF_RELA
117 select NO_BOOTMEM
118 select OF
119 select OF_EARLY_FLATTREE
120 select OF_RESERVED_MEM
121 select PCI_ECAM if ACPI
122 select POWER_RESET
123 select POWER_SUPPLY
124 select SPARSE_IRQ
125 select SYSCTL_EXCEPTION_TRACE
126 select THREAD_INFO_IN_TASK
127 help
128 ARM 64-bit (AArch64) Linux support.
129
130config 64BIT
131 def_bool y
132
133config ARCH_PHYS_ADDR_T_64BIT
134 def_bool y
135
136config MMU
137 def_bool y
138
139config ARM64_PAGE_SHIFT
140 int
141 default 16 if ARM64_64K_PAGES
142 default 14 if ARM64_16K_PAGES
143 default 12
144
145config ARM64_CONT_SHIFT
146 int
147 default 5 if ARM64_64K_PAGES
148 default 7 if ARM64_16K_PAGES
149 default 4
150
151config ARCH_MMAP_RND_BITS_MIN
152 default 14 if ARM64_64K_PAGES
153 default 16 if ARM64_16K_PAGES
154 default 18
155
156# max bits determined by the following formula:
157# VA_BITS - PAGE_SHIFT - 3
158config ARCH_MMAP_RND_BITS_MAX
159 default 19 if ARM64_VA_BITS=36
160 default 24 if ARM64_VA_BITS=39
161 default 27 if ARM64_VA_BITS=42
162 default 30 if ARM64_VA_BITS=47
163 default 29 if ARM64_VA_BITS=48 && ARM64_64K_PAGES
164 default 31 if ARM64_VA_BITS=48 && ARM64_16K_PAGES
165 default 33 if ARM64_VA_BITS=48
166 default 14 if ARM64_64K_PAGES
167 default 16 if ARM64_16K_PAGES
168 default 18
169
170config ARCH_MMAP_RND_COMPAT_BITS_MIN
171 default 7 if ARM64_64K_PAGES
172 default 9 if ARM64_16K_PAGES
173 default 11
174
175config ARCH_MMAP_RND_COMPAT_BITS_MAX
176 default 16
177
178config NO_IOPORT_MAP
179 def_bool y if !PCI
180
181config STACKTRACE_SUPPORT
182 def_bool y
183
184config ILLEGAL_POINTER_VALUE
185 hex
186 default 0xdead000000000000
187
188config LOCKDEP_SUPPORT
189 def_bool y
190
191config TRACE_IRQFLAGS_SUPPORT
192 def_bool y
193
194config RWSEM_XCHGADD_ALGORITHM
195 def_bool y
196
197config GENERIC_BUG
198 def_bool y
199 depends on BUG
200
201config GENERIC_BUG_RELATIVE_POINTERS
202 def_bool y
203 depends on GENERIC_BUG
204
205config GENERIC_HWEIGHT
206 def_bool y
207
208config GENERIC_CSUM
209 def_bool y
210
211config GENERIC_CALIBRATE_DELAY
212 def_bool y
213
214config ZONE_DMA
215 def_bool y
216
217config HAVE_GENERIC_GUP
218 def_bool y
219
220config ARCH_DMA_ADDR_T_64BIT
221 def_bool y
222
223config NEED_DMA_MAP_STATE
224 def_bool y
225
226config NEED_SG_DMA_LENGTH
227 def_bool y
228
229config SMP
230 def_bool y
231
232config SWIOTLB
233 def_bool y
234
235config IOMMU_HELPER
236 def_bool SWIOTLB
237
238config KERNEL_MODE_NEON
239 def_bool y
240
241config FIX_EARLYCON_MEM
242 def_bool y
243
244config PGTABLE_LEVELS
245 int
246 default 2 if ARM64_16K_PAGES && ARM64_VA_BITS_36
247 default 2 if ARM64_64K_PAGES && ARM64_VA_BITS_42
248 default 3 if ARM64_64K_PAGES && ARM64_VA_BITS_48
249 default 3 if ARM64_4K_PAGES && ARM64_VA_BITS_39
250 default 3 if ARM64_16K_PAGES && ARM64_VA_BITS_47
251 default 4 if !ARM64_64K_PAGES && ARM64_VA_BITS_48
252
253config ARCH_SUPPORTS_UPROBES
254 def_bool y
255
256config ARCH_PROC_KCORE_TEXT
257 def_bool y
258
259source "init/Kconfig"
260
261source "kernel/Kconfig.freezer"
262
263source "arch/arm64/Kconfig.platforms"
264
265menu "Bus support"
266
267config PCI
268 bool "PCI support"
269 help
270 This feature enables support for PCI bus system. If you say Y
271 here, the kernel will include drivers and infrastructure code
272 to support PCI bus devices.
273
274config PCI_DOMAINS
275 def_bool PCI
276
277config PCI_DOMAINS_GENERIC
278 def_bool PCI
279
280config PCI_SYSCALL
281 def_bool PCI
282
283source "drivers/pci/Kconfig"
284
285endmenu
286
287menu "Kernel Features"
288
289menu "ARM errata workarounds via the alternatives framework"
290
291config ARM64_ERRATUM_826319
292 bool "Cortex-A53: 826319: System might deadlock if a write cannot complete until read data is accepted"
293 default y
294 help
295 This option adds an alternative code sequence to work around ARM
296 erratum 826319 on Cortex-A53 parts up to r0p2 with an AMBA 4 ACE or
297 AXI master interface and an L2 cache.
298
299 If a Cortex-A53 uses an AMBA AXI4 ACE interface to other processors
300 and is unable to accept a certain write via this interface, it will
301 not progress on read data presented on the read data channel and the
302 system can deadlock.
303
304 The workaround promotes data cache clean instructions to
305 data cache clean-and-invalidate.
306 Please note that this does not necessarily enable the workaround,
307 as it depends on the alternative framework, which will only patch
308 the kernel if an affected CPU is detected.
309
310 If unsure, say Y.
311
312config ARM64_ERRATUM_827319
313 bool "Cortex-A53: 827319: Data cache clean instructions might cause overlapping transactions to the interconnect"
314 default y
315 help
316 This option adds an alternative code sequence to work around ARM
317 erratum 827319 on Cortex-A53 parts up to r0p2 with an AMBA 5 CHI
318 master interface and an L2 cache.
319
320 Under certain conditions this erratum can cause a clean line eviction
321 to occur at the same time as another transaction to the same address
322 on the AMBA 5 CHI interface, which can cause data corruption if the
323 interconnect reorders the two transactions.
324
325 The workaround promotes data cache clean instructions to
326 data cache clean-and-invalidate.
327 Please note that this does not necessarily enable the workaround,
328 as it depends on the alternative framework, which will only patch
329 the kernel if an affected CPU is detected.
330
331 If unsure, say Y.
332
333config ARM64_ERRATUM_824069
334 bool "Cortex-A53: 824069: Cache line might not be marked as clean after a CleanShared snoop"
335 default y
336 help
337 This option adds an alternative code sequence to work around ARM
338 erratum 824069 on Cortex-A53 parts up to r0p2 when it is connected
339 to a coherent interconnect.
340
341 If a Cortex-A53 processor is executing a store or prefetch for
342 write instruction at the same time as a processor in another
343 cluster is executing a cache maintenance operation to the same
344 address, then this erratum might cause a clean cache line to be
345 incorrectly marked as dirty.
346
347 The workaround promotes data cache clean instructions to
348 data cache clean-and-invalidate.
349 Please note that this option does not necessarily enable the
350 workaround, as it depends on the alternative framework, which will
351 only patch the kernel if an affected CPU is detected.
352
353 If unsure, say Y.
354
355config ARM64_ERRATUM_819472
356 bool "Cortex-A53: 819472: Store exclusive instructions might cause data corruption"
357 default y
358 help
359 This option adds an alternative code sequence to work around ARM
360 erratum 819472 on Cortex-A53 parts up to r0p1 with an L2 cache
361 present when it is connected to a coherent interconnect.
362
363 If the processor is executing a load and store exclusive sequence at
364 the same time as a processor in another cluster is executing a cache
365 maintenance operation to the same address, then this erratum might
366 cause data corruption.
367
368 The workaround promotes data cache clean instructions to
369 data cache clean-and-invalidate.
370 Please note that this does not necessarily enable the workaround,
371 as it depends on the alternative framework, which will only patch
372 the kernel if an affected CPU is detected.
373
374 If unsure, say Y.
375
376config ARM64_ERRATUM_832075
377 bool "Cortex-A57: 832075: possible deadlock on mixing exclusive memory accesses with device loads"
378 default y
379 help
380 This option adds an alternative code sequence to work around ARM
381 erratum 832075 on Cortex-A57 parts up to r1p2.
382
383 Affected Cortex-A57 parts might deadlock when exclusive load/store
384 instructions to Write-Back memory are mixed with Device loads.
385
386 The workaround is to promote device loads to use Load-Acquire
387 semantics.
388 Please note that this does not necessarily enable the workaround,
389 as it depends on the alternative framework, which will only patch
390 the kernel if an affected CPU is detected.
391
392 If unsure, say Y.
393
394config ARM64_ERRATUM_834220
395 bool "Cortex-A57: 834220: Stage 2 translation fault might be incorrectly reported in presence of a Stage 1 fault"
396 depends on KVM
397 default y
398 help
399 This option adds an alternative code sequence to work around ARM
400 erratum 834220 on Cortex-A57 parts up to r1p2.
401
402 Affected Cortex-A57 parts might report a Stage 2 translation
403 fault as the result of a Stage 1 fault for load crossing a
404 page boundary when there is a permission or device memory
405 alignment fault at Stage 1 and a translation fault at Stage 2.
406
407 The workaround is to verify that the Stage 1 translation
408 doesn't generate a fault before handling the Stage 2 fault.
409 Please note that this does not necessarily enable the workaround,
410 as it depends on the alternative framework, which will only patch
411 the kernel if an affected CPU is detected.
412
413 If unsure, say Y.
414
415config ARM64_ERRATUM_845719
416 bool "Cortex-A53: 845719: a load might read incorrect data"
417 depends on COMPAT
418 default y
419 help
420 This option adds an alternative code sequence to work around ARM
421 erratum 845719 on Cortex-A53 parts up to r0p4.
422
423 When running a compat (AArch32) userspace on an affected Cortex-A53
424 part, a load at EL0 from a virtual address that matches the bottom 32
425 bits of the virtual address used by a recent load at (AArch64) EL1
426 might return incorrect data.
427
428 The workaround is to write the contextidr_el1 register on exception
429 return to a 32-bit task.
430 Please note that this does not necessarily enable the workaround,
431 as it depends on the alternative framework, which will only patch
432 the kernel if an affected CPU is detected.
433
434 If unsure, say Y.
435
436config ARM64_ERRATUM_843419
437 bool "Cortex-A53: 843419: A load or store might access an incorrect address"
438 default y if !LTO_CLANG
439 select ARM64_MODULE_CMODEL_LARGE if MODULES
440 help
441 This option links the kernel with '--fix-cortex-a53-843419' and
442 builds modules using the large memory model in order to avoid the use
443 of the ADRP instruction, which can cause a subsequent memory access
444 to use an incorrect address on Cortex-A53 parts up to r0p4.
445
446 If unsure, say Y.
447
448config ARM64_ERRATUM_1024718
449 bool "Cortex-A55: 1024718: Update of DBM/AP bits without break before make might result in incorrect update"
450 default y
451 help
452 This option adds work around for Arm Cortex-A55 Erratum 1024718.
453
454 Affected Cortex-A55 cores (r0p0, r0p1, r1p0) could cause incorrect
455 update of the hardware dirty bit when the DBM/AP bits are updated
456 without a break-before-make. The work around is to disable the usage
457 of hardware DBM locally on the affected cores. CPUs not affected by
458 erratum will continue to use the feature.
459
460 If unsure, say Y.
461
462config CAVIUM_ERRATUM_22375
463 bool "Cavium erratum 22375, 24313"
464 default y
465 help
466 Enable workaround for erratum 22375, 24313.
467
468 This implements two gicv3-its errata workarounds for ThunderX. Both
469 with small impact affecting only ITS table allocation.
470
471 erratum 22375: only alloc 8MB table size
472 erratum 24313: ignore memory access type
473
474 The fixes are in ITS initialization and basically ignore memory access
475 type and table size provided by the TYPER and BASER registers.
476
477 If unsure, say Y.
478
479config CAVIUM_ERRATUM_23144
480 bool "Cavium erratum 23144: ITS SYNC hang on dual socket system"
481 depends on NUMA
482 default y
483 help
484 ITS SYNC command hang for cross node io and collections/cpu mapping.
485
486 If unsure, say Y.
487
488config CAVIUM_ERRATUM_23154
489 bool "Cavium erratum 23154: Access to ICC_IAR1_EL1 is not sync'ed"
490 default y
491 help
492 The gicv3 of ThunderX requires a modified version for
493 reading the IAR status to ensure data synchronization
494 (access to icc_iar1_el1 is not sync'ed before and after).
495
496 If unsure, say Y.
497
498config CAVIUM_ERRATUM_27456
499 bool "Cavium erratum 27456: Broadcast TLBI instructions may cause icache corruption"
500 default y
501 help
502 On ThunderX T88 pass 1.x through 2.1 parts, broadcast TLBI
503 instructions may cause the icache to become corrupted if it
504 contains data for a non-current ASID. The fix is to
505 invalidate the icache when changing the mm context.
506
507 If unsure, say Y.
508
509config CAVIUM_ERRATUM_30115
510 bool "Cavium erratum 30115: Guest may disable interrupts in host"
511 default y
512 help
513 On ThunderX T88 pass 1.x through 2.2, T81 pass 1.0 through
514 1.2, and T83 Pass 1.0, KVM guest execution may disable
515 interrupts in host. Trapping both GICv3 group-0 and group-1
516 accesses sidesteps the issue.
517
518 If unsure, say Y.
519
520config QCOM_FALKOR_ERRATUM_1003
521 bool "Falkor E1003: Incorrect translation due to ASID change"
522 default y
523 help
524 On Falkor v1, an incorrect ASID may be cached in the TLB when ASID
525 and BADDR are changed together in TTBRx_EL1. Since we keep the ASID
526 in TTBR1_EL1, this situation only occurs in the entry trampoline and
527 then only for entries in the walk cache, since the leaf translation
528 is unchanged. Work around the erratum by invalidating the walk cache
529 entries for the trampoline before entering the kernel proper.
530
531config QCOM_FALKOR_ERRATUM_1009
532 bool "Falkor E1009: Prematurely complete a DSB after a TLBI"
533 default y
534 help
535 On Falkor v1, the CPU may prematurely complete a DSB following a
536 TLBI xxIS invalidate maintenance operation. Repeat the TLBI operation
537 one more time to fix the issue.
538
539 If unsure, say Y.
540
541config QCOM_QDF2400_ERRATUM_0065
542 bool "QDF2400 E0065: Incorrect GITS_TYPER.ITT_Entry_size"
543 default y
544 help
545 On Qualcomm Datacenter Technologies QDF2400 SoC, ITS hardware reports
546 ITE size incorrectly. The GITS_TYPER.ITT_Entry_size field should have
547 been indicated as 16Bytes (0xf), not 8Bytes (0x7).
548
549 If unsure, say Y.
550
551config QCOM_FALKOR_ERRATUM_E1041
552 bool "Falkor E1041: Speculative instruction fetches might cause errant memory access"
553 default y
554 help
555 Falkor CPU may speculatively fetch instructions from an improper
556 memory location when MMU translation is changed from SCTLR_ELn[M]=1
557 to SCTLR_ELn[M]=0. Prefix an ISB instruction to fix the problem.
558
559 If unsure, say Y.
560
561endmenu
562
563
564choice
565 prompt "Page size"
566 default ARM64_4K_PAGES
567 help
568 Page size (translation granule) configuration.
569
570config ARM64_4K_PAGES
571 bool "4KB"
572 help
573 This feature enables 4KB pages support.
574
575config ARM64_16K_PAGES
576 bool "16KB"
577 help
578 The system will use 16KB pages support. AArch32 emulation
579 requires applications compiled with 16K (or a multiple of 16K)
580 aligned segments.
581
582config ARM64_64K_PAGES
583 bool "64KB"
584 help
585 This feature enables 64KB pages support (4KB by default)
586 allowing only two levels of page tables and faster TLB
587 look-up. AArch32 emulation requires applications compiled
588 with 64K aligned segments.
589
590endchoice
591
592choice
593 prompt "Virtual address space size"
594 default ARM64_VA_BITS_39 if ARM64_4K_PAGES
595 default ARM64_VA_BITS_47 if ARM64_16K_PAGES
596 default ARM64_VA_BITS_42 if ARM64_64K_PAGES
597 help
598 Allows choosing one of multiple possible virtual address
599 space sizes. The level of translation table is determined by
600 a combination of page size and virtual address space size.
601
602config ARM64_VA_BITS_36
603 bool "36-bit" if EXPERT
604 depends on ARM64_16K_PAGES
605
606config ARM64_VA_BITS_39
607 bool "39-bit"
608 depends on ARM64_4K_PAGES
609
610config ARM64_VA_BITS_42
611 bool "42-bit"
612 depends on ARM64_64K_PAGES
613
614config ARM64_VA_BITS_47
615 bool "47-bit"
616 depends on ARM64_16K_PAGES
617
618config ARM64_VA_BITS_48
619 bool "48-bit"
620
621endchoice
622
623config ARM64_VA_BITS
624 int
625 default 36 if ARM64_VA_BITS_36
626 default 39 if ARM64_VA_BITS_39
627 default 42 if ARM64_VA_BITS_42
628 default 47 if ARM64_VA_BITS_47
629 default 48 if ARM64_VA_BITS_48
630
631config CPU_BIG_ENDIAN
632 bool "Build big-endian kernel"
633 help
634 Say Y if you plan on running a kernel in big-endian mode.
635
636config SCHED_MC
637 bool "Multi-core scheduler support"
638 help
639 Multi-core scheduler support improves the CPU scheduler's decision
640 making when dealing with multi-core CPU chips at a cost of slightly
641 increased overhead in some places. If unsure say N here.
642
643config SCHED_SMT
644 bool "SMT scheduler support"
645 help
646 Improves the CPU scheduler's decision making when dealing with
647 MultiThreading at a cost of slightly increased overhead in some
648 places. If unsure say N here.
649
650config NR_CPUS
651 int "Maximum number of CPUs (2-4096)"
652 range 2 4096
653 # These have to remain sorted largest to smallest
654 default "64"
655
656config HOTPLUG_CPU
657 bool "Support for hot-pluggable CPUs"
658 select GENERIC_IRQ_MIGRATION
659 help
660 Say Y here to experiment with turning CPUs off and on. CPUs
661 can be controlled through /sys/devices/system/cpu.
662
663# Common NUMA Features
664config NUMA
665 bool "Numa Memory Allocation and Scheduler Support"
666 select ACPI_NUMA if ACPI
667 select OF_NUMA
668 help
669 Enable NUMA (Non Uniform Memory Access) support.
670
671 The kernel will try to allocate memory used by a CPU on the
672 local memory of the CPU and add some more
673 NUMA awareness to the kernel.
674
675config NODES_SHIFT
676 int "Maximum NUMA Nodes (as a power of 2)"
677 range 1 10
678 default "2"
679 depends on NEED_MULTIPLE_NODES
680 help
681 Specify the maximum number of NUMA Nodes available on the target
682 system. Increases memory reserved to accommodate various tables.
683
684config USE_PERCPU_NUMA_NODE_ID
685 def_bool y
686 depends on NUMA
687
688config HAVE_SETUP_PER_CPU_AREA
689 def_bool y
690 depends on NUMA
691
692config NEED_PER_CPU_EMBED_FIRST_CHUNK
693 def_bool y
694 depends on NUMA
695
696config HOLES_IN_ZONE
697 def_bool y
698
699source kernel/Kconfig.preempt
700source kernel/Kconfig.hz
701
702config ARCH_SUPPORTS_DEBUG_PAGEALLOC
703 def_bool y
704
705config ARCH_HAS_HOLES_MEMORYMODEL
706 def_bool y if SPARSEMEM
707
708config ARCH_SPARSEMEM_ENABLE
709 def_bool y
710 select SPARSEMEM_VMEMMAP_ENABLE
711
712config ARCH_SPARSEMEM_DEFAULT
713 def_bool ARCH_SPARSEMEM_ENABLE
714
715config ARCH_SELECT_MEMORY_MODEL
716 def_bool ARCH_SPARSEMEM_ENABLE
717
718config HAVE_ARCH_PFN_VALID
719 def_bool ARCH_HAS_HOLES_MEMORYMODEL || !SPARSEMEM
720
721config HW_PERF_EVENTS
722 def_bool y
723 depends on ARM_PMU
724
725config SYS_SUPPORTS_HUGETLBFS
726 def_bool y
727
728config ARCH_WANT_HUGE_PMD_SHARE
729 def_bool y if ARM64_4K_PAGES || (ARM64_16K_PAGES && !ARM64_VA_BITS_36)
730
731config ARCH_HAS_CACHE_LINE_SIZE
732 def_bool y
733
734source "mm/Kconfig"
735
736config SECCOMP
737 bool "Enable seccomp to safely compute untrusted bytecode"
738 ---help---
739 This kernel feature is useful for number crunching applications
740 that may need to compute untrusted bytecode during their
741 execution. By using pipes or other transports made available to
742 the process as file descriptors supporting the read/write
743 syscalls, it's possible to isolate those applications in
744 their own address space using seccomp. Once seccomp is
745 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
746 and the task is only allowed to execute a few safe syscalls
747 defined by each seccomp mode.
748
749config PARAVIRT
750 bool "Enable paravirtualization code"
751 help
752 This changes the kernel so it can modify itself when it is run
753 under a hypervisor, potentially improving performance significantly
754 over full virtualization.
755
756config PARAVIRT_TIME_ACCOUNTING
757 bool "Paravirtual steal time accounting"
758 select PARAVIRT
759 default n
760 help
761 Select this option to enable fine granularity task steal time
762 accounting. Time spent executing other tasks in parallel with
763 the current vCPU is discounted from the vCPU power. To account for
764 that, there can be a small performance impact.
765
766 If in doubt, say N here.
767
768config KEXEC
769 depends on PM_SLEEP_SMP
770 select KEXEC_CORE
771 bool "kexec system call"
772 ---help---
773 kexec is a system call that implements the ability to shutdown your
774 current kernel, and to start another kernel. It is like a reboot
775 but it is independent of the system firmware. And like a reboot
776 you can start any kernel with it, not just Linux.
777
778config CRASH_DUMP
779 bool "Build kdump crash kernel"
780 help
781 Generate crash dump after being started by kexec. This should
782 be normally only set in special crash dump kernels which are
783 loaded in the main kernel with kexec-tools into a specially
784 reserved region and then later executed after a crash by
785 kdump/kexec.
786
787 For more details see Documentation/kdump/kdump.txt
788
789config XEN_DOM0
790 def_bool y
791 depends on XEN
792
793config XEN
794 bool "Xen guest support on ARM64"
795 depends on ARM64 && OF
796 select SWIOTLB_XEN
797 select PARAVIRT
798 help
799 Say Y if you want to run Linux in a Virtual Machine on Xen on ARM64.
800
801config FORCE_MAX_ZONEORDER
802 int
803 default "14" if (ARM64_64K_PAGES && TRANSPARENT_HUGEPAGE)
804 default "12" if (ARM64_16K_PAGES && TRANSPARENT_HUGEPAGE)
805 default "11"
806 help
807 The kernel memory allocator divides physically contiguous memory
808 blocks into "zones", where each zone is a power of two number of
809 pages. This option selects the largest power of two that the kernel
810 keeps in the memory allocator. If you need to allocate very large
811 blocks of physically contiguous memory, then you may need to
812 increase this value.
813
814 This config option is actually maximum order plus one. For example,
815 a value of 11 means that the largest free memory block is 2^10 pages.
816
817 We make sure that we can allocate upto a HugePage size for each configuration.
818 Hence we have :
819 MAX_ORDER = (PMD_SHIFT - PAGE_SHIFT) + 1 => PAGE_SHIFT - 2
820
821 However for 4K, we choose a higher default value, 11 as opposed to 10, giving us
822 4M allocations matching the default size used by generic code.
823
824config UNMAP_KERNEL_AT_EL0
825 bool "Unmap kernel when running in userspace (aka \"KAISER\")" if EXPERT
826 default y
827 help
828 Speculation attacks against some high-performance processors can
829 be used to bypass MMU permission checks and leak kernel data to
830 userspace. This can be defended against by unmapping the kernel
831 when running in userspace, mapping it back in on exception entry
832 via a trampoline page in the vector table.
833
834 If unsure, say Y.
835
836config HARDEN_BRANCH_PREDICTOR
837 bool "Harden the branch predictor against aliasing attacks" if EXPERT
838 default y
839 help
840 Speculation attacks against some high-performance processors rely on
841 being able to manipulate the branch predictor for a victim context by
842 executing aliasing branches in the attacker context. Such attacks
843 can be partially mitigated against by clearing internal branch
844 predictor state and limiting the prediction logic in some situations.
845
846 This config option will take CPU-specific actions to harden the
847 branch predictor against aliasing attacks and may rely on specific
848 instruction sequences or control bits being set by the system
849 firmware.
850
851 If unsure, say Y.
852
853config ARM64_SSBD
854 bool "Speculative Store Bypass Disable" if EXPERT
855 default y
856 help
857 This enables mitigation of the bypassing of previous stores
858 by speculative loads.
859
860 If unsure, say Y.
861
862menuconfig ARMV8_DEPRECATED
863 bool "Emulate deprecated/obsolete ARMv8 instructions"
864 depends on COMPAT
865 help
866 Legacy software support may require certain instructions
867 that have been deprecated or obsoleted in the architecture.
868
869 Enable this config to enable selective emulation of these
870 features.
871
872 If unsure, say Y
873
874if ARMV8_DEPRECATED
875
876config SWP_EMULATION
877 bool "Emulate SWP/SWPB instructions"
878 help
879 ARMv8 obsoletes the use of A32 SWP/SWPB instructions such that
880 they are always undefined. Say Y here to enable software
881 emulation of these instructions for userspace using LDXR/STXR.
882
883 In some older versions of glibc [<=2.8] SWP is used during futex
884 trylock() operations with the assumption that the code will not
885 be preempted. This invalid assumption may be more likely to fail
886 with SWP emulation enabled, leading to deadlock of the user
887 application.
888
889 NOTE: when accessing uncached shared regions, LDXR/STXR rely
890 on an external transaction monitoring block called a global
891 monitor to maintain update atomicity. If your system does not
892 implement a global monitor, this option can cause programs that
893 perform SWP operations to uncached memory to deadlock.
894
895 If unsure, say Y
896
897config CP15_BARRIER_EMULATION
898 bool "Emulate CP15 Barrier instructions"
899 help
900 The CP15 barrier instructions - CP15ISB, CP15DSB, and
901 CP15DMB - are deprecated in ARMv8 (and ARMv7). It is
902 strongly recommended to use the ISB, DSB, and DMB
903 instructions instead.
904
905 Say Y here to enable software emulation of these
906 instructions for AArch32 userspace code. When this option is
907 enabled, CP15 barrier usage is traced which can help
908 identify software that needs updating.
909
910 If unsure, say Y
911
912config SETEND_EMULATION
913 bool "Emulate SETEND instruction"
914 help
915 The SETEND instruction alters the data-endianness of the
916 AArch32 EL0, and is deprecated in ARMv8.
917
918 Say Y here to enable software emulation of the instruction
919 for AArch32 userspace code.
920
921 Note: All the cpus on the system must have mixed endian support at EL0
922 for this feature to be enabled. If a new CPU - which doesn't support mixed
923 endian - is hotplugged in after this feature has been enabled, there could
924 be unexpected results in the applications.
925
926 If unsure, say Y
927endif
928
929config ARM64_SW_TTBR0_PAN
930 bool "Emulate Privileged Access Never using TTBR0_EL1 switching"
931 help
932 Enabling this option prevents the kernel from accessing
933 user-space memory directly by pointing TTBR0_EL1 to a reserved
934 zeroed area and reserved ASID. The user access routines
935 restore the valid TTBR0_EL1 temporarily.
936
937menu "ARMv8.1 architectural features"
938
939config ARM64_HW_AFDBM
940 bool "Support for hardware updates of the Access and Dirty page flags"
941 default y
942 help
943 The ARMv8.1 architecture extensions introduce support for
944 hardware updates of the access and dirty information in page
945 table entries. When enabled in TCR_EL1 (HA and HD bits) on
946 capable processors, accesses to pages with PTE_AF cleared will
947 set this bit instead of raising an access flag fault.
948 Similarly, writes to read-only pages with the DBM bit set will
949 clear the read-only bit (AP[2]) instead of raising a
950 permission fault.
951
952 Kernels built with this configuration option enabled continue
953 to work on pre-ARMv8.1 hardware and the performance impact is
954 minimal. If unsure, say Y.
955
956config ARM64_PAN
957 bool "Enable support for Privileged Access Never (PAN)"
958 default y
959 help
960 Privileged Access Never (PAN; part of the ARMv8.1 Extensions)
961 prevents the kernel or hypervisor from accessing user-space (EL0)
962 memory directly.
963
964 Choosing this option will cause any unprotected (not using
965 copy_to_user et al) memory access to fail with a permission fault.
966
967 The feature is detected at runtime, and will remain as a 'nop'
968 instruction if the cpu does not implement the feature.
969
970config ARM64_LSE_ATOMICS
971 bool "Atomic instructions"
972 help
973 As part of the Large System Extensions, ARMv8.1 introduces new
974 atomic instructions that are designed specifically to scale in
975 very large systems.
976
977 Say Y here to make use of these instructions for the in-kernel
978 atomic routines. This incurs a small overhead on CPUs that do
979 not support these instructions and requires the kernel to be
980 built with binutils >= 2.25.
981
982config ARM64_VHE
983 bool "Enable support for Virtualization Host Extensions (VHE)"
984 default y
985 help
986 Virtualization Host Extensions (VHE) allow the kernel to run
987 directly at EL2 (instead of EL1) on processors that support
988 it. This leads to better performance for KVM, as they reduce
989 the cost of the world switch.
990
991 Selecting this option allows the VHE feature to be detected
992 at runtime, and does not affect processors that do not
993 implement this feature.
994
995endmenu
996
997menu "ARMv8.2 architectural features"
998
999config ARM64_UAO
1000 bool "Enable support for User Access Override (UAO)"
1001 default y
1002 help
1003 User Access Override (UAO; part of the ARMv8.2 Extensions)
1004 causes the 'unprivileged' variant of the load/store instructions to
1005 be overriden to be privileged.
1006
1007 This option changes get_user() and friends to use the 'unprivileged'
1008 variant of the load/store instructions. This ensures that user-space
1009 really did have access to the supplied memory. When addr_limit is
1010 set to kernel memory the UAO bit will be set, allowing privileged
1011 access to kernel memory.
1012
1013 Choosing this option will cause copy_to_user() et al to use user-space
1014 memory permissions.
1015
1016 The feature is detected at runtime, the kernel will use the
1017 regular load/store instructions if the cpu does not implement the
1018 feature.
1019
1020config ARM64_PMEM
1021 bool "Enable support for persistent memory"
1022 select ARCH_HAS_PMEM_API
1023 select ARCH_HAS_UACCESS_FLUSHCACHE
1024 help
1025 Say Y to enable support for the persistent memory API based on the
1026 ARMv8.2 DCPoP feature.
1027
1028 The feature is detected at runtime, and the kernel will use DC CVAC
1029 operations if DC CVAP is not supported (following the behaviour of
1030 DC CVAP itself if the system does not define a point of persistence).
1031
1032endmenu
1033
1034config ARM64_MODULE_CMODEL_LARGE
1035 bool
1036
1037config ARM64_MODULE_PLTS
1038 bool
1039 select ARM64_MODULE_CMODEL_LARGE
1040 select HAVE_MOD_ARCH_SPECIFIC
1041
1042config RELOCATABLE
1043 bool
1044 help
1045 This builds the kernel as a Position Independent Executable (PIE),
1046 which retains all relocation metadata required to relocate the
1047 kernel binary at runtime to a different virtual address than the
1048 address it was linked at.
1049 Since AArch64 uses the RELA relocation format, this requires a
1050 relocation pass at runtime even if the kernel is loaded at the
1051 same address it was linked at.
1052
1053config RANDOMIZE_BASE
1054 bool "Randomize the address of the kernel image"
1055 select ARM64_MODULE_PLTS if MODULES
1056 select RELOCATABLE
1057 help
1058 Randomizes the virtual address at which the kernel image is
1059 loaded, as a security feature that deters exploit attempts
1060 relying on knowledge of the location of kernel internals.
1061
1062 It is the bootloader's job to provide entropy, by passing a
1063 random u64 value in /chosen/kaslr-seed at kernel entry.
1064
1065 When booting via the UEFI stub, it will invoke the firmware's
1066 EFI_RNG_PROTOCOL implementation (if available) to supply entropy
1067 to the kernel proper. In addition, it will randomise the physical
1068 location of the kernel Image as well.
1069
1070 If unsure, say N.
1071
1072config RANDOMIZE_MODULE_REGION_FULL
1073 bool "Randomize the module region independently from the core kernel"
1074 depends on RANDOMIZE_BASE && !LTO_CLANG
1075 default y
1076 help
1077 Randomizes the location of the module region without considering the
1078 location of the core kernel. This way, it is impossible for modules
1079 to leak information about the location of core kernel data structures
1080 but it does imply that function calls between modules and the core
1081 kernel will need to be resolved via veneers in the module PLT.
1082
1083 When this option is not set, the module region will be randomized over
1084 a limited range that contains the [_stext, _etext] interval of the
1085 core kernel, so branch relocations are always in range.
1086
1087endmenu
1088
1089menu "Boot options"
1090
1091config ARM64_ACPI_PARKING_PROTOCOL
1092 bool "Enable support for the ARM64 ACPI parking protocol"
1093 depends on ACPI
1094 help
1095 Enable support for the ARM64 ACPI parking protocol. If disabled
1096 the kernel will not allow booting through the ARM64 ACPI parking
1097 protocol even if the corresponding data is present in the ACPI
1098 MADT table.
1099
1100config CMDLINE
1101 string "Default kernel command string"
1102 default ""
1103 help
1104 Provide a set of default command-line options at build time by
1105 entering them here. As a minimum, you should specify the the
1106 root device (e.g. root=/dev/nfs).
1107
1108choice
1109 prompt "Kernel command line type" if CMDLINE != ""
1110 default CMDLINE_FROM_BOOTLOADER
1111
1112config CMDLINE_FROM_BOOTLOADER
1113 bool "Use bootloader kernel arguments if available"
1114 help
1115 Uses the command-line options passed by the boot loader. If
1116 the boot loader doesn't provide any, the default kernel command
1117 string provided in CMDLINE will be used.
1118
1119config CMDLINE_EXTEND
1120 bool "Extend bootloader kernel arguments"
1121 help
1122 The command-line arguments provided by the boot loader will be
1123 appended to the default kernel command string.
1124
1125config CMDLINE_FORCE
1126 bool "Always use the default kernel command string"
1127 help
1128 Always use the default kernel command string, even if the boot
1129 loader passes other arguments to the kernel.
1130 This is useful if you cannot or don't want to change the
1131 command-line options your boot loader passes to the kernel.
1132endchoice
1133
1134config EFI_STUB
1135 bool
1136
1137config EFI
1138 bool "UEFI runtime support"
1139 depends on OF && !CPU_BIG_ENDIAN
1140 select LIBFDT
1141 select UCS2_STRING
1142 select EFI_PARAMS_FROM_FDT
1143 select EFI_RUNTIME_WRAPPERS
1144 select EFI_STUB
1145 select EFI_ARMSTUB
1146 default y
1147 help
1148 This option provides support for runtime services provided
1149 by UEFI firmware (such as non-volatile variables, realtime
1150 clock, and platform reset). A UEFI stub is also provided to
1151 allow the kernel to be booted as an EFI application. This
1152 is only useful on systems that have UEFI firmware.
1153
1154config DMI
1155 bool "Enable support for SMBIOS (DMI) tables"
1156 depends on EFI
1157 default y
1158 help
1159 This enables SMBIOS/DMI feature for systems.
1160
1161 This option is only useful on systems that have UEFI firmware.
1162 However, even with this option, the resultant kernel should
1163 continue to boot on existing non-UEFI platforms.
1164
1165config BUILD_ARM64_APPENDED_DTB_IMAGE
1166 bool "Build a concatenated Image.gz/dtb by default"
1167 depends on OF
1168 help
1169 Enabling this option will cause a concatenated Image.gz and list of
1170 DTBs to be built by default (instead of a standalone Image.gz.)
1171 The image will built in arch/arm64/boot/Image.gz-dtb
1172
1173choice
1174 prompt "Appended DTB Kernel Image name"
1175 depends on BUILD_ARM64_APPENDED_DTB_IMAGE
1176 help
1177 Enabling this option will cause a specific kernel image Image or
1178 Image.gz to be used for final image creation.
1179 The image will built in arch/arm64/boot/IMAGE-NAME-dtb
1180
1181 config IMG_GZ_DTB
1182 bool "Image.gz-dtb"
1183 config IMG_DTB
1184 bool "Image-dtb"
1185endchoice
1186
1187config BUILD_ARM64_APPENDED_KERNEL_IMAGE_NAME
1188 string
1189 depends on BUILD_ARM64_APPENDED_DTB_IMAGE
1190 default "Image.gz-dtb" if IMG_GZ_DTB
1191 default "Image-dtb" if IMG_DTB
1192
1193config BUILD_ARM64_APPENDED_DTB_IMAGE_NAMES
1194 string "Default dtb names"
1195 depends on BUILD_ARM64_APPENDED_DTB_IMAGE
1196 help
1197 Space separated list of names of dtbs to append when
1198 building a concatenated Image.gz-dtb.
1199
1200endmenu
1201
1202menu "Userspace binary formats"
1203
1204source "fs/Kconfig.binfmt"
1205
1206config COMPAT
1207 bool "Kernel support for 32-bit EL0"
1208 depends on ARM64_4K_PAGES || EXPERT
1209 select COMPAT_BINFMT_ELF if BINFMT_ELF
1210 select HAVE_UID16
1211 select OLD_SIGSUSPEND3
1212 select COMPAT_OLD_SIGACTION
1213 help
1214 This option enables support for a 32-bit EL0 running under a 64-bit
1215 kernel at EL1. AArch32-specific components such as system calls,
1216 the user helper functions, VFP support and the ptrace interface are
1217 handled appropriately by the kernel.
1218
1219 If you use a page size other than 4KB (i.e, 16KB or 64KB), please be aware
1220 that you will only be able to execute AArch32 binaries that were compiled
1221 with page size aligned segments.
1222
1223 If you want to execute 32-bit userspace applications, say Y.
1224
1225config SYSVIPC_COMPAT
1226 def_bool y
1227 depends on COMPAT && SYSVIPC
1228
1229endmenu
1230
1231menu "Power management options"
1232
1233source "kernel/power/Kconfig"
1234
1235config ARCH_HIBERNATION_POSSIBLE
1236 def_bool y
1237 depends on CPU_PM
1238
1239config ARCH_HIBERNATION_HEADER
1240 def_bool y
1241 depends on HIBERNATION
1242
1243config ARCH_SUSPEND_POSSIBLE
1244 def_bool y
1245
1246endmenu
1247
1248menu "CPU Power Management"
1249
1250source "drivers/cpuidle/Kconfig"
1251
1252source "drivers/cpufreq/Kconfig"
1253
1254endmenu
1255
1256source "net/Kconfig"
1257
1258source "drivers/Kconfig"
1259
1260source "drivers/firmware/Kconfig"
1261
1262source "drivers/acpi/Kconfig"
1263
1264source "fs/Kconfig"
1265
1266source "arch/arm64/kvm/Kconfig"
1267
1268source "arch/arm64/Kconfig.debug"
1269
1270source "security/Kconfig"
1271
1272source "crypto/Kconfig"
1273if CRYPTO
1274source "arch/arm64/crypto/Kconfig"
1275endif
1276
1277source "lib/Kconfig"