]> Git Repo - linux.git/blame - arch/arm64/Kconfig
Merge tag 'spi-v5.11' of git://git.kernel.org/pub/scm/linux/kernel/git/broonie/spi
[linux.git] / arch / arm64 / Kconfig
CommitLineData
ec8f24b7 1# SPDX-License-Identifier: GPL-2.0-only
8c2c3df3
CM
2config ARM64
3 def_bool y
b6197b93 4 select ACPI_CCA_REQUIRED if ACPI
d8f4f161 5 select ACPI_GENERIC_GSI if ACPI
5f1ae4eb 6 select ACPI_GTDT if ACPI
c6bb8f89 7 select ACPI_IORT if ACPI
6933de0c 8 select ACPI_REDUCED_HARDWARE_ONLY if ACPI
52146173 9 select ACPI_MCFG if (ACPI && PCI)
888125a7 10 select ACPI_SPCR_TABLE if ACPI
0ce82232 11 select ACPI_PPTT if ACPI
09587a09 12 select ARCH_HAS_DEBUG_WX
ab7876a9 13 select ARCH_BINFMT_ELF_STATE
ec6d06ef 14 select ARCH_HAS_DEBUG_VIRTUAL
399145f9 15 select ARCH_HAS_DEBUG_VM_PGTABLE
21266be9 16 select ARCH_HAS_DEVMEM_IS_ALLOWED
13bf5ced 17 select ARCH_HAS_DMA_PREP_COHERENT
38b04a74 18 select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI
e75bef2a 19 select ARCH_HAS_FAST_MULTIPLIER
6974f0c4 20 select ARCH_HAS_FORTIFY_SOURCE
957e3fac 21 select ARCH_HAS_GCOV_PROFILE_ALL
4eb0716e 22 select ARCH_HAS_GIGANTIC_PAGE
5e4c7549 23 select ARCH_HAS_KCOV
d8ae8a37 24 select ARCH_HAS_KEEPINITRD
f1e3a12b 25 select ARCH_HAS_MEMBARRIER_SYNC_CORE
0ebeea8c 26 select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
73b20c84 27 select ARCH_HAS_PTE_DEVMAP
3010a5ea 28 select ARCH_HAS_PTE_SPECIAL
347cb6af 29 select ARCH_HAS_SETUP_DMA_OPS
4739d53f 30 select ARCH_HAS_SET_DIRECT_MAP
d2852a22 31 select ARCH_HAS_SET_MEMORY
5fc57df2 32 select ARCH_STACKWALK
ad21fc4f
LA
33 select ARCH_HAS_STRICT_KERNEL_RWX
34 select ARCH_HAS_STRICT_MODULE_RWX
886643b7
CH
35 select ARCH_HAS_SYNC_DMA_FOR_DEVICE
36 select ARCH_HAS_SYNC_DMA_FOR_CPU
4378a7d4 37 select ARCH_HAS_SYSCALL_WRAPPER
dc2acded 38 select ARCH_HAS_TEARDOWN_DMA_OPS if IOMMU_SUPPORT
1f85008e 39 select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
ab7876a9 40 select ARCH_HAVE_ELF_PROT
396a5d4a 41 select ARCH_HAVE_NMI_SAFE_CMPXCHG
7ef858da
TG
42 select ARCH_INLINE_READ_LOCK if !PREEMPTION
43 select ARCH_INLINE_READ_LOCK_BH if !PREEMPTION
44 select ARCH_INLINE_READ_LOCK_IRQ if !PREEMPTION
45 select ARCH_INLINE_READ_LOCK_IRQSAVE if !PREEMPTION
46 select ARCH_INLINE_READ_UNLOCK if !PREEMPTION
47 select ARCH_INLINE_READ_UNLOCK_BH if !PREEMPTION
48 select ARCH_INLINE_READ_UNLOCK_IRQ if !PREEMPTION
49 select ARCH_INLINE_READ_UNLOCK_IRQRESTORE if !PREEMPTION
50 select ARCH_INLINE_WRITE_LOCK if !PREEMPTION
51 select ARCH_INLINE_WRITE_LOCK_BH if !PREEMPTION
52 select ARCH_INLINE_WRITE_LOCK_IRQ if !PREEMPTION
53 select ARCH_INLINE_WRITE_LOCK_IRQSAVE if !PREEMPTION
54 select ARCH_INLINE_WRITE_UNLOCK if !PREEMPTION
55 select ARCH_INLINE_WRITE_UNLOCK_BH if !PREEMPTION
56 select ARCH_INLINE_WRITE_UNLOCK_IRQ if !PREEMPTION
57 select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE if !PREEMPTION
58 select ARCH_INLINE_SPIN_TRYLOCK if !PREEMPTION
59 select ARCH_INLINE_SPIN_TRYLOCK_BH if !PREEMPTION
60 select ARCH_INLINE_SPIN_LOCK if !PREEMPTION
61 select ARCH_INLINE_SPIN_LOCK_BH if !PREEMPTION
62 select ARCH_INLINE_SPIN_LOCK_IRQ if !PREEMPTION
63 select ARCH_INLINE_SPIN_LOCK_IRQSAVE if !PREEMPTION
64 select ARCH_INLINE_SPIN_UNLOCK if !PREEMPTION
65 select ARCH_INLINE_SPIN_UNLOCK_BH if !PREEMPTION
66 select ARCH_INLINE_SPIN_UNLOCK_IRQ if !PREEMPTION
67 select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE if !PREEMPTION
350e88ba 68 select ARCH_KEEP_MEMBLOCK
c63c8700 69 select ARCH_USE_CMPXCHG_LOCKREF
bf7f15c5 70 select ARCH_USE_GNU_PROPERTY
087133ac 71 select ARCH_USE_QUEUED_RWLOCKS
c1109047 72 select ARCH_USE_QUEUED_SPINLOCKS
50479d58 73 select ARCH_USE_SYM_ANNOTATIONS
5d6ad668 74 select ARCH_SUPPORTS_DEBUG_PAGEALLOC
c484f256 75 select ARCH_SUPPORTS_MEMORY_FAILURE
5287569a 76 select ARCH_SUPPORTS_SHADOW_CALL_STACK if CC_HAVE_SHADOW_CALL_STACK
4badad35 77 select ARCH_SUPPORTS_ATOMIC_RMW
c12d3362 78 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 && (GCC_VERSION >= 50000 || CC_IS_CLANG)
56166230 79 select ARCH_SUPPORTS_NUMA_BALANCING
84c187af 80 select ARCH_WANT_COMPAT_IPC_PARSE_VERSION if COMPAT
81c22041 81 select ARCH_WANT_DEFAULT_BPF_JIT
67f3977f 82 select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT
b6f35981 83 select ARCH_WANT_FRAME_POINTERS
3876d4a3 84 select ARCH_WANT_HUGE_PMD_SHARE if ARM64_4K_PAGES || (ARM64_16K_PAGES && !ARM64_VA_BITS_36)
59612b24 85 select ARCH_WANT_LD_ORPHAN_WARN
f0b7f8a4 86 select ARCH_HAS_UBSAN_SANITIZE_ALL
25c92a37 87 select ARM_AMBA
1aee5d7a 88 select ARM_ARCH_TIMER
c4188edc 89 select ARM_GIC
875cbf3e 90 select AUDIT_ARCH_COMPAT_GENERIC
3ee80364 91 select ARM_GIC_V2M if PCI
021f6537 92 select ARM_GIC_V3
3ee80364 93 select ARM_GIC_V3_ITS if PCI
bff60792 94 select ARM_PSCI_FW
10916706 95 select BUILDTIME_TABLE_SORT
db2789b5 96 select CLONE_BACKWARDS
7ca2ef33 97 select COMMON_CLK
166936ba 98 select CPU_PM if (SUSPEND || CPU_IDLE)
7481cddf 99 select CRC32
7bc13fd3 100 select DCACHE_WORD_ACCESS
0c3b3171 101 select DMA_DIRECT_REMAP
ef37566c 102 select EDAC_SUPPORT
2f34f173 103 select FRAME_POINTER
d4932f9e 104 select GENERIC_ALLOCATOR
2ef7a295 105 select GENERIC_ARCH_TOPOLOGY
8c2c3df3 106 select GENERIC_CLOCKEVENTS
4b3dc967 107 select GENERIC_CLOCKEVENTS_BROADCAST
3be1a5c4 108 select GENERIC_CPU_AUTOPROBE
61ae1321 109 select GENERIC_CPU_VULNERABILITIES
bf4b558e 110 select GENERIC_EARLY_IOREMAP
2314ee4d 111 select GENERIC_IDLE_POLL_SETUP
d3afc7f1 112 select GENERIC_IRQ_IPI
78ae2e1c 113 select GENERIC_IRQ_MULTI_HANDLER
8c2c3df3
CM
114 select GENERIC_IRQ_PROBE
115 select GENERIC_IRQ_SHOW
6544e67b 116 select GENERIC_IRQ_SHOW_LEVEL
cb61f676 117 select GENERIC_PCI_IOMAP
102f45fd 118 select GENERIC_PTDUMP
65cd4f6c 119 select GENERIC_SCHED_CLOCK
8c2c3df3 120 select GENERIC_SMP_IDLE_THREAD
12a0ef7b
WD
121 select GENERIC_STRNCPY_FROM_USER
122 select GENERIC_STRNLEN_USER
8c2c3df3 123 select GENERIC_TIME_VSYSCALL
28b1a824 124 select GENERIC_GETTIMEOFDAY
9614cc57 125 select GENERIC_VDSO_TIME_NS
a1ddc74a 126 select HANDLE_DOMAIN_IRQ
8c2c3df3 127 select HARDIRQS_SW_RESEND
45544eee 128 select HAVE_MOVE_PMD
f5308c89 129 select HAVE_MOVE_PUD
eb01d42a 130 select HAVE_PCI
9f9a35a7 131 select HAVE_ACPI_APEI if (ACPI && EFI)
5284e1b4 132 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
875cbf3e 133 select HAVE_ARCH_AUDITSYSCALL
8e7a4cef 134 select HAVE_ARCH_BITREVERSE
689eae42 135 select HAVE_ARCH_COMPILER_H
324420bf 136 select HAVE_ARCH_HUGE_VMAP
9732cafd 137 select HAVE_ARCH_JUMP_LABEL
c296146c 138 select HAVE_ARCH_JUMP_LABEL_RELATIVE
e17d8025 139 select HAVE_ARCH_KASAN if !(ARM64_16K_PAGES && ARM64_VA_BITS_48)
2d4acb90 140 select HAVE_ARCH_KASAN_SW_TAGS if HAVE_ARCH_KASAN
9529247d 141 select HAVE_ARCH_KGDB
8f0d3aa9
DC
142 select HAVE_ARCH_MMAP_RND_BITS
143 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT
4f5b0c17 144 select HAVE_ARCH_PFN_VALID
271ca788 145 select HAVE_ARCH_PREL32_RELOCATIONS
a1ae65b2 146 select HAVE_ARCH_SECCOMP_FILTER
0b3e3366 147 select HAVE_ARCH_STACKLEAK
9e8084d3 148 select HAVE_ARCH_THREAD_STRUCT_WHITELIST
8c2c3df3 149 select HAVE_ARCH_TRACEHOOK
8ee70879 150 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
e3067861 151 select HAVE_ARCH_VMAP_STACK
8ee70879 152 select HAVE_ARM_SMCCC
2ff2b7ec 153 select HAVE_ASM_MODVERSIONS
6077776b 154 select HAVE_EBPF_JIT
af64d2aa 155 select HAVE_C_RECORDMCOUNT
5284e1b4 156 select HAVE_CMPXCHG_DOUBLE
95eff6b2 157 select HAVE_CMPXCHG_LOCAL
8ee70879 158 select HAVE_CONTEXT_TRACKING
9b2a60c4 159 select HAVE_DEBUG_BUGVERBOSE
b69ec42b 160 select HAVE_DEBUG_KMEMLEAK
6ac2104d 161 select HAVE_DMA_CONTIGUOUS
bd7d38db 162 select HAVE_DYNAMIC_FTRACE
3b23e499
TD
163 select HAVE_DYNAMIC_FTRACE_WITH_REGS \
164 if $(cc-option,-fpatchable-function-entry=2)
50afc33a 165 select HAVE_EFFICIENT_UNALIGNED_ACCESS
67a929e0 166 select HAVE_FAST_GUP
af64d2aa 167 select HAVE_FTRACE_MCOUNT_RECORD
819e50e2 168 select HAVE_FUNCTION_TRACER
42d038c4 169 select HAVE_FUNCTION_ERROR_INJECTION
819e50e2 170 select HAVE_FUNCTION_GRAPH_TRACER
6b90bd4b 171 select HAVE_GCC_PLUGINS
8c2c3df3 172 select HAVE_HW_BREAKPOINT if PERF_EVENTS
24da208d 173 select HAVE_IRQ_TIME_ACCOUNTING
396a5d4a 174 select HAVE_NMI
55834a77 175 select HAVE_PATA_PLATFORM
8c2c3df3 176 select HAVE_PERF_EVENTS
ce4b2c01 177 select HAVE_PERF_EVENTS_NMI if ARM64_PSEUDO_NMI && HW_PERF_EVENTS
367c820e 178 select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && HAVE_PERF_EVENTS_NMI
2ee0d7fd
JP
179 select HAVE_PERF_REGS
180 select HAVE_PERF_USER_STACK_DUMP
0a8ea52c 181 select HAVE_REGS_AND_STACK_ACCESS_API
a823c35f 182 select HAVE_FUNCTION_ARG_ACCESS_API
98346023 183 select HAVE_FUTEX_CMPXCHG if FUTEX
ff2e6d72 184 select MMU_GATHER_RCU_TABLE_FREE
409d5db4 185 select HAVE_RSEQ
d148eac0 186 select HAVE_STACKPROTECTOR
055b1212 187 select HAVE_SYSCALL_TRACEPOINTS
2dd0e8d2 188 select HAVE_KPROBES
cd1ee3b1 189 select HAVE_KRETPROBES
28b1a824 190 select HAVE_GENERIC_VDSO
876945db 191 select IOMMU_DMA if IOMMU_SUPPORT
8c2c3df3 192 select IRQ_DOMAIN
e8557d1f 193 select IRQ_FORCED_THREADING
fea2acaa 194 select MODULES_USE_ELF_RELA
f616ab59 195 select NEED_DMA_MAP_STATE
86596f0a 196 select NEED_SG_DMA_LENGTH
8c2c3df3
CM
197 select OF
198 select OF_EARLY_FLATTREE
2eac9c2d 199 select PCI_DOMAINS_GENERIC if PCI
52146173 200 select PCI_ECAM if (ACPI && PCI)
20f1b79d 201 select PCI_SYSCALL if PCI
aa1e8ec1
CM
202 select POWER_RESET
203 select POWER_SUPPLY
8c2c3df3 204 select SPARSE_IRQ
09230cbc 205 select SWIOTLB
7ac57a89 206 select SYSCTL_EXCEPTION_TRACE
c02433dd 207 select THREAD_INFO_IN_TASK
8c2c3df3
CM
208 help
209 ARM 64-bit (AArch64) Linux support.
210
211config 64BIT
212 def_bool y
213
8c2c3df3
CM
214config MMU
215 def_bool y
216
030c4d24
MR
217config ARM64_PAGE_SHIFT
218 int
219 default 16 if ARM64_64K_PAGES
220 default 14 if ARM64_16K_PAGES
221 default 12
222
c0d6de32 223config ARM64_CONT_PTE_SHIFT
030c4d24
MR
224 int
225 default 5 if ARM64_64K_PAGES
226 default 7 if ARM64_16K_PAGES
227 default 4
228
e6765941
GS
229config ARM64_CONT_PMD_SHIFT
230 int
231 default 5 if ARM64_64K_PAGES
232 default 5 if ARM64_16K_PAGES
233 default 4
234
8f0d3aa9
DC
235config ARCH_MMAP_RND_BITS_MIN
236 default 14 if ARM64_64K_PAGES
237 default 16 if ARM64_16K_PAGES
238 default 18
239
240# max bits determined by the following formula:
241# VA_BITS - PAGE_SHIFT - 3
242config ARCH_MMAP_RND_BITS_MAX
243 default 19 if ARM64_VA_BITS=36
244 default 24 if ARM64_VA_BITS=39
245 default 27 if ARM64_VA_BITS=42
246 default 30 if ARM64_VA_BITS=47
247 default 29 if ARM64_VA_BITS=48 && ARM64_64K_PAGES
248 default 31 if ARM64_VA_BITS=48 && ARM64_16K_PAGES
249 default 33 if ARM64_VA_BITS=48
250 default 14 if ARM64_64K_PAGES
251 default 16 if ARM64_16K_PAGES
252 default 18
253
254config ARCH_MMAP_RND_COMPAT_BITS_MIN
255 default 7 if ARM64_64K_PAGES
256 default 9 if ARM64_16K_PAGES
257 default 11
258
259config ARCH_MMAP_RND_COMPAT_BITS_MAX
260 default 16
261
ce816fa8 262config NO_IOPORT_MAP
d1e6dc91 263 def_bool y if !PCI
8c2c3df3
CM
264
265config STACKTRACE_SUPPORT
266 def_bool y
267
bf0c4e04
JVS
268config ILLEGAL_POINTER_VALUE
269 hex
270 default 0xdead000000000000
271
8c2c3df3
CM
272config LOCKDEP_SUPPORT
273 def_bool y
274
275config TRACE_IRQFLAGS_SUPPORT
276 def_bool y
277
9fb7410f
DM
278config GENERIC_BUG
279 def_bool y
280 depends on BUG
281
282config GENERIC_BUG_RELATIVE_POINTERS
283 def_bool y
284 depends on GENERIC_BUG
285
8c2c3df3
CM
286config GENERIC_HWEIGHT
287 def_bool y
288
289config GENERIC_CSUM
290 def_bool y
291
292config GENERIC_CALIBRATE_DELAY
293 def_bool y
294
1a8e1cef
NSJ
295config ZONE_DMA
296 bool "Support DMA zone" if EXPERT
297 default y
298
ad67f5a6 299config ZONE_DMA32
0c1f14ed
MC
300 bool "Support DMA32 zone" if EXPERT
301 default y
8c2c3df3 302
4ab21506
RM
303config ARCH_ENABLE_MEMORY_HOTPLUG
304 def_bool y
305
bbd6ec60
AK
306config ARCH_ENABLE_MEMORY_HOTREMOVE
307 def_bool y
308
4b3dc967
WD
309config SMP
310 def_bool y
311
4cfb3613
AB
312config KERNEL_MODE_NEON
313 def_bool y
314
92cc15fc
RH
315config FIX_EARLYCON_MEM
316 def_bool y
317
9f25e6ad
KS
318config PGTABLE_LEVELS
319 int
21539939 320 default 2 if ARM64_16K_PAGES && ARM64_VA_BITS_36
9f25e6ad 321 default 2 if ARM64_64K_PAGES && ARM64_VA_BITS_42
b6d00d47 322 default 3 if ARM64_64K_PAGES && (ARM64_VA_BITS_48 || ARM64_VA_BITS_52)
9f25e6ad 323 default 3 if ARM64_4K_PAGES && ARM64_VA_BITS_39
44eaacf1
SP
324 default 3 if ARM64_16K_PAGES && ARM64_VA_BITS_47
325 default 4 if !ARM64_64K_PAGES && ARM64_VA_BITS_48
9f25e6ad 326
9842ceae
PA
327config ARCH_SUPPORTS_UPROBES
328 def_bool y
329
8f360948
AB
330config ARCH_PROC_KCORE_TEXT
331 def_bool y
332
8bf9284d
VM
333config BROKEN_GAS_INST
334 def_bool !$(as-instr,1:\n.inst 0\n.rept . - 1b\n\nnop\n.endr\n)
335
6bd1d0be
SC
336config KASAN_SHADOW_OFFSET
337 hex
338 depends on KASAN
f4693c27
AB
339 default 0xdfff800000000000 if (ARM64_VA_BITS_48 || ARM64_VA_BITS_52) && !KASAN_SW_TAGS
340 default 0xdfffc00000000000 if ARM64_VA_BITS_47 && !KASAN_SW_TAGS
341 default 0xdffffe0000000000 if ARM64_VA_BITS_42 && !KASAN_SW_TAGS
342 default 0xdfffffc000000000 if ARM64_VA_BITS_39 && !KASAN_SW_TAGS
343 default 0xdffffff800000000 if ARM64_VA_BITS_36 && !KASAN_SW_TAGS
344 default 0xefff800000000000 if (ARM64_VA_BITS_48 || ARM64_VA_BITS_52) && KASAN_SW_TAGS
345 default 0xefffc00000000000 if ARM64_VA_BITS_47 && KASAN_SW_TAGS
346 default 0xeffffe0000000000 if ARM64_VA_BITS_42 && KASAN_SW_TAGS
347 default 0xefffffc000000000 if ARM64_VA_BITS_39 && KASAN_SW_TAGS
348 default 0xeffffff800000000 if ARM64_VA_BITS_36 && KASAN_SW_TAGS
6bd1d0be
SC
349 default 0xffffffffffffffff
350
6a377491 351source "arch/arm64/Kconfig.platforms"
8c2c3df3 352
8c2c3df3
CM
353menu "Kernel Features"
354
c0a01b84
AP
355menu "ARM errata workarounds via the alternatives framework"
356
c9460dcb 357config ARM64_WORKAROUND_CLEAN_CACHE
bc15cf70 358 bool
c9460dcb 359
c0a01b84
AP
360config ARM64_ERRATUM_826319
361 bool "Cortex-A53: 826319: System might deadlock if a write cannot complete until read data is accepted"
362 default y
c9460dcb 363 select ARM64_WORKAROUND_CLEAN_CACHE
c0a01b84
AP
364 help
365 This option adds an alternative code sequence to work around ARM
366 erratum 826319 on Cortex-A53 parts up to r0p2 with an AMBA 4 ACE or
367 AXI master interface and an L2 cache.
368
369 If a Cortex-A53 uses an AMBA AXI4 ACE interface to other processors
370 and is unable to accept a certain write via this interface, it will
371 not progress on read data presented on the read data channel and the
372 system can deadlock.
373
374 The workaround promotes data cache clean instructions to
375 data cache clean-and-invalidate.
376 Please note that this does not necessarily enable the workaround,
377 as it depends on the alternative framework, which will only patch
378 the kernel if an affected CPU is detected.
379
380 If unsure, say Y.
381
382config ARM64_ERRATUM_827319
383 bool "Cortex-A53: 827319: Data cache clean instructions might cause overlapping transactions to the interconnect"
384 default y
c9460dcb 385 select ARM64_WORKAROUND_CLEAN_CACHE
c0a01b84
AP
386 help
387 This option adds an alternative code sequence to work around ARM
388 erratum 827319 on Cortex-A53 parts up to r0p2 with an AMBA 5 CHI
389 master interface and an L2 cache.
390
391 Under certain conditions this erratum can cause a clean line eviction
392 to occur at the same time as another transaction to the same address
393 on the AMBA 5 CHI interface, which can cause data corruption if the
394 interconnect reorders the two transactions.
395
396 The workaround promotes data cache clean instructions to
397 data cache clean-and-invalidate.
398 Please note that this does not necessarily enable the workaround,
399 as it depends on the alternative framework, which will only patch
400 the kernel if an affected CPU is detected.
401
402 If unsure, say Y.
403
404config ARM64_ERRATUM_824069
405 bool "Cortex-A53: 824069: Cache line might not be marked as clean after a CleanShared snoop"
406 default y
c9460dcb 407 select ARM64_WORKAROUND_CLEAN_CACHE
c0a01b84
AP
408 help
409 This option adds an alternative code sequence to work around ARM
410 erratum 824069 on Cortex-A53 parts up to r0p2 when it is connected
411 to a coherent interconnect.
412
413 If a Cortex-A53 processor is executing a store or prefetch for
414 write instruction at the same time as a processor in another
415 cluster is executing a cache maintenance operation to the same
416 address, then this erratum might cause a clean cache line to be
417 incorrectly marked as dirty.
418
419 The workaround promotes data cache clean instructions to
420 data cache clean-and-invalidate.
421 Please note that this option does not necessarily enable the
422 workaround, as it depends on the alternative framework, which will
423 only patch the kernel if an affected CPU is detected.
424
425 If unsure, say Y.
426
427config ARM64_ERRATUM_819472
428 bool "Cortex-A53: 819472: Store exclusive instructions might cause data corruption"
429 default y
c9460dcb 430 select ARM64_WORKAROUND_CLEAN_CACHE
c0a01b84
AP
431 help
432 This option adds an alternative code sequence to work around ARM
433 erratum 819472 on Cortex-A53 parts up to r0p1 with an L2 cache
434 present when it is connected to a coherent interconnect.
435
436 If the processor is executing a load and store exclusive sequence at
437 the same time as a processor in another cluster is executing a cache
438 maintenance operation to the same address, then this erratum might
439 cause data corruption.
440
441 The workaround promotes data cache clean instructions to
442 data cache clean-and-invalidate.
443 Please note that this does not necessarily enable the workaround,
444 as it depends on the alternative framework, which will only patch
445 the kernel if an affected CPU is detected.
446
447 If unsure, say Y.
448
449config ARM64_ERRATUM_832075
450 bool "Cortex-A57: 832075: possible deadlock on mixing exclusive memory accesses with device loads"
451 default y
452 help
453 This option adds an alternative code sequence to work around ARM
454 erratum 832075 on Cortex-A57 parts up to r1p2.
455
456 Affected Cortex-A57 parts might deadlock when exclusive load/store
457 instructions to Write-Back memory are mixed with Device loads.
458
459 The workaround is to promote device loads to use Load-Acquire
460 semantics.
461 Please note that this does not necessarily enable the workaround,
498cd5c3
MZ
462 as it depends on the alternative framework, which will only patch
463 the kernel if an affected CPU is detected.
464
465 If unsure, say Y.
466
467config ARM64_ERRATUM_834220
468 bool "Cortex-A57: 834220: Stage 2 translation fault might be incorrectly reported in presence of a Stage 1 fault"
469 depends on KVM
470 default y
471 help
472 This option adds an alternative code sequence to work around ARM
473 erratum 834220 on Cortex-A57 parts up to r1p2.
474
475 Affected Cortex-A57 parts might report a Stage 2 translation
476 fault as the result of a Stage 1 fault for load crossing a
477 page boundary when there is a permission or device memory
478 alignment fault at Stage 1 and a translation fault at Stage 2.
479
480 The workaround is to verify that the Stage 1 translation
481 doesn't generate a fault before handling the Stage 2 fault.
482 Please note that this does not necessarily enable the workaround,
c0a01b84
AP
483 as it depends on the alternative framework, which will only patch
484 the kernel if an affected CPU is detected.
485
486 If unsure, say Y.
487
905e8c5d
WD
488config ARM64_ERRATUM_845719
489 bool "Cortex-A53: 845719: a load might read incorrect data"
490 depends on COMPAT
491 default y
492 help
493 This option adds an alternative code sequence to work around ARM
494 erratum 845719 on Cortex-A53 parts up to r0p4.
495
496 When running a compat (AArch32) userspace on an affected Cortex-A53
497 part, a load at EL0 from a virtual address that matches the bottom 32
498 bits of the virtual address used by a recent load at (AArch64) EL1
499 might return incorrect data.
500
501 The workaround is to write the contextidr_el1 register on exception
502 return to a 32-bit task.
503 Please note that this does not necessarily enable the workaround,
504 as it depends on the alternative framework, which will only patch
505 the kernel if an affected CPU is detected.
506
507 If unsure, say Y.
508
df057cc7
WD
509config ARM64_ERRATUM_843419
510 bool "Cortex-A53: 843419: A load or store might access an incorrect address"
df057cc7 511 default y
a257e025 512 select ARM64_MODULE_PLTS if MODULES
df057cc7 513 help
6ffe9923 514 This option links the kernel with '--fix-cortex-a53-843419' and
a257e025
AB
515 enables PLT support to replace certain ADRP instructions, which can
516 cause subsequent memory accesses to use an incorrect address on
517 Cortex-A53 parts up to r0p4.
df057cc7
WD
518
519 If unsure, say Y.
520
ece1397c
SP
521config ARM64_ERRATUM_1024718
522 bool "Cortex-A55: 1024718: Update of DBM/AP bits without break before make might result in incorrect update"
523 default y
524 help
bc15cf70 525 This option adds a workaround for ARM Cortex-A55 Erratum 1024718.
ece1397c
SP
526
527 Affected Cortex-A55 cores (r0p0, r0p1, r1p0) could cause incorrect
528 update of the hardware dirty bit when the DBM/AP bits are updated
bc15cf70 529 without a break-before-make. The workaround is to disable the usage
ece1397c 530 of hardware DBM locally on the affected cores. CPUs not affected by
bc15cf70 531 this erratum will continue to use the feature.
df057cc7
WD
532
533 If unsure, say Y.
534
a5325089 535config ARM64_ERRATUM_1418040
6989303a 536 bool "Cortex-A76/Neoverse-N1: MRC read following MRRC read of specific Generic Timer in AArch32 might give incorrect result"
95b861a4 537 default y
c2b5bba3 538 depends on COMPAT
95b861a4 539 help
24cf262d 540 This option adds a workaround for ARM Cortex-A76/Neoverse-N1
a5325089 541 errata 1188873 and 1418040.
95b861a4 542
a5325089 543 Affected Cortex-A76/Neoverse-N1 cores (r0p0 to r3p1) could
6989303a
MZ
544 cause register corruption when accessing the timer registers
545 from AArch32 userspace.
95b861a4
MZ
546
547 If unsure, say Y.
548
02ab1f50 549config ARM64_WORKAROUND_SPECULATIVE_AT
e85d68fa
SP
550 bool
551
a457b0f7 552config ARM64_ERRATUM_1165522
02ab1f50 553 bool "Cortex-A76: 1165522: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
a457b0f7 554 default y
02ab1f50 555 select ARM64_WORKAROUND_SPECULATIVE_AT
a457b0f7 556 help
bc15cf70 557 This option adds a workaround for ARM Cortex-A76 erratum 1165522.
a457b0f7
MZ
558
559 Affected Cortex-A76 cores (r0p0, r1p0, r2p0) could end-up with
560 corrupted TLBs by speculating an AT instruction during a guest
561 context switch.
562
563 If unsure, say Y.
564
02ab1f50
AS
565config ARM64_ERRATUM_1319367
566 bool "Cortex-A57/A72: 1319537: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
567 default y
568 select ARM64_WORKAROUND_SPECULATIVE_AT
569 help
570 This option adds work arounds for ARM Cortex-A57 erratum 1319537
571 and A72 erratum 1319367
572
573 Cortex-A57 and A72 cores could end-up with corrupted TLBs by
574 speculating an AT instruction during a guest context switch.
575
576 If unsure, say Y.
577
275fa0ea 578config ARM64_ERRATUM_1530923
02ab1f50 579 bool "Cortex-A55: 1530923: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
275fa0ea 580 default y
02ab1f50 581 select ARM64_WORKAROUND_SPECULATIVE_AT
275fa0ea
SP
582 help
583 This option adds a workaround for ARM Cortex-A55 erratum 1530923.
584
585 Affected Cortex-A55 cores (r0p0, r0p1, r1p0, r2p0) could end-up with
586 corrupted TLBs by speculating an AT instruction during a guest
587 context switch.
588
589 If unsure, say Y.
a457b0f7 590
ebcea694
GU
591config ARM64_WORKAROUND_REPEAT_TLBI
592 bool
593
ce8c80c5
CM
594config ARM64_ERRATUM_1286807
595 bool "Cortex-A76: Modification of the translation table for a virtual address might lead to read-after-read ordering violation"
596 default y
597 select ARM64_WORKAROUND_REPEAT_TLBI
598 help
bc15cf70 599 This option adds a workaround for ARM Cortex-A76 erratum 1286807.
ce8c80c5
CM
600
601 On the affected Cortex-A76 cores (r0p0 to r3p0), if a virtual
602 address for a cacheable mapping of a location is being
603 accessed by a core while another core is remapping the virtual
604 address to a new physical page using the recommended
605 break-before-make sequence, then under very rare circumstances
606 TLBI+DSB completes before a read using the translation being
607 invalidated has been observed by other observers. The
608 workaround repeats the TLBI+DSB operation.
609
969f5ea6
WD
610config ARM64_ERRATUM_1463225
611 bool "Cortex-A76: Software Step might prevent interrupt recognition"
612 default y
613 help
614 This option adds a workaround for Arm Cortex-A76 erratum 1463225.
615
616 On the affected Cortex-A76 cores (r0p0 to r3p1), software stepping
617 of a system call instruction (SVC) can prevent recognition of
618 subsequent interrupts when software stepping is disabled in the
619 exception handler of the system call and either kernel debugging
620 is enabled or VHE is in use.
621
622 Work around the erratum by triggering a dummy step exception
623 when handling a system call from a task that is being stepped
624 in a VHE configuration of the kernel.
625
626 If unsure, say Y.
627
05460849
JM
628config ARM64_ERRATUM_1542419
629 bool "Neoverse-N1: workaround mis-ordering of instruction fetches"
630 default y
631 help
632 This option adds a workaround for ARM Neoverse-N1 erratum
633 1542419.
634
635 Affected Neoverse-N1 cores could execute a stale instruction when
636 modified by another CPU. The workaround depends on a firmware
637 counterpart.
638
639 Workaround the issue by hiding the DIC feature from EL0. This
640 forces user-space to perform cache maintenance.
641
642 If unsure, say Y.
643
96d389ca
RH
644config ARM64_ERRATUM_1508412
645 bool "Cortex-A77: 1508412: workaround deadlock on sequence of NC/Device load and store exclusive or PAR read"
646 default y
647 help
648 This option adds a workaround for Arm Cortex-A77 erratum 1508412.
649
650 Affected Cortex-A77 cores (r0p0, r1p0) could deadlock on a sequence
651 of a store-exclusive or read of PAR_EL1 and a load with device or
652 non-cacheable memory attributes. The workaround depends on a firmware
653 counterpart.
654
655 KVM guests must also have the workaround implemented or they can
656 deadlock the system.
657
658 Work around the issue by inserting DMB SY barriers around PAR_EL1
659 register reads and warning KVM users. The DMB barrier is sufficient
660 to prevent a speculative PAR_EL1 read.
661
662 If unsure, say Y.
663
94100970
RR
664config CAVIUM_ERRATUM_22375
665 bool "Cavium erratum 22375, 24313"
666 default y
667 help
bc15cf70 668 Enable workaround for errata 22375 and 24313.
94100970
RR
669
670 This implements two gicv3-its errata workarounds for ThunderX. Both
bc15cf70 671 with a small impact affecting only ITS table allocation.
94100970
RR
672
673 erratum 22375: only alloc 8MB table size
674 erratum 24313: ignore memory access type
675
676 The fixes are in ITS initialization and basically ignore memory access
677 type and table size provided by the TYPER and BASER registers.
678
679 If unsure, say Y.
680
fbf8f40e
GK
681config CAVIUM_ERRATUM_23144
682 bool "Cavium erratum 23144: ITS SYNC hang on dual socket system"
683 depends on NUMA
684 default y
685 help
686 ITS SYNC command hang for cross node io and collections/cpu mapping.
687
688 If unsure, say Y.
689
6d4e11c5
RR
690config CAVIUM_ERRATUM_23154
691 bool "Cavium erratum 23154: Access to ICC_IAR1_EL1 is not sync'ed"
692 default y
693 help
694 The gicv3 of ThunderX requires a modified version for
695 reading the IAR status to ensure data synchronization
696 (access to icc_iar1_el1 is not sync'ed before and after).
697
698 If unsure, say Y.
699
104a0c02
AP
700config CAVIUM_ERRATUM_27456
701 bool "Cavium erratum 27456: Broadcast TLBI instructions may cause icache corruption"
702 default y
703 help
704 On ThunderX T88 pass 1.x through 2.1 parts, broadcast TLBI
705 instructions may cause the icache to become corrupted if it
706 contains data for a non-current ASID. The fix is to
707 invalidate the icache when changing the mm context.
708
709 If unsure, say Y.
710
690a3415
DD
711config CAVIUM_ERRATUM_30115
712 bool "Cavium erratum 30115: Guest may disable interrupts in host"
713 default y
714 help
715 On ThunderX T88 pass 1.x through 2.2, T81 pass 1.0 through
716 1.2, and T83 Pass 1.0, KVM guest execution may disable
717 interrupts in host. Trapping both GICv3 group-0 and group-1
718 accesses sidesteps the issue.
719
720 If unsure, say Y.
721
603afdc9
MZ
722config CAVIUM_TX2_ERRATUM_219
723 bool "Cavium ThunderX2 erratum 219: PRFM between TTBR change and ISB fails"
724 default y
725 help
726 On Cavium ThunderX2, a load, store or prefetch instruction between a
727 TTBR update and the corresponding context synchronizing operation can
728 cause a spurious Data Abort to be delivered to any hardware thread in
729 the CPU core.
730
731 Work around the issue by avoiding the problematic code sequence and
732 trapping KVM guest TTBRx_EL1 writes to EL2 when SMT is enabled. The
733 trap handler performs the corresponding register access, skips the
734 instruction and ensures context synchronization by virtue of the
735 exception return.
736
737 If unsure, say Y.
738
ebcea694
GU
739config FUJITSU_ERRATUM_010001
740 bool "Fujitsu-A64FX erratum E#010001: Undefined fault may occur wrongly"
741 default y
742 help
743 This option adds a workaround for Fujitsu-A64FX erratum E#010001.
744 On some variants of the Fujitsu-A64FX cores ver(1.0, 1.1), memory
745 accesses may cause undefined fault (Data abort, DFSC=0b111111).
746 This fault occurs under a specific hardware condition when a
747 load/store instruction performs an address translation using:
748 case-1 TTBR0_EL1 with TCR_EL1.NFD0 == 1.
749 case-2 TTBR0_EL2 with TCR_EL2.NFD0 == 1.
750 case-3 TTBR1_EL1 with TCR_EL1.NFD1 == 1.
751 case-4 TTBR1_EL2 with TCR_EL2.NFD1 == 1.
752
753 The workaround is to ensure these bits are clear in TCR_ELx.
754 The workaround only affects the Fujitsu-A64FX.
755
756 If unsure, say Y.
757
758config HISILICON_ERRATUM_161600802
759 bool "Hip07 161600802: Erroneous redistributor VLPI base"
760 default y
761 help
762 The HiSilicon Hip07 SoC uses the wrong redistributor base
763 when issued ITS commands such as VMOVP and VMAPP, and requires
764 a 128kB offset to be applied to the target address in this commands.
765
766 If unsure, say Y.
767
38fd94b0
CC
768config QCOM_FALKOR_ERRATUM_1003
769 bool "Falkor E1003: Incorrect translation due to ASID change"
770 default y
38fd94b0
CC
771 help
772 On Falkor v1, an incorrect ASID may be cached in the TLB when ASID
d1777e68
WD
773 and BADDR are changed together in TTBRx_EL1. Since we keep the ASID
774 in TTBR1_EL1, this situation only occurs in the entry trampoline and
775 then only for entries in the walk cache, since the leaf translation
776 is unchanged. Work around the erratum by invalidating the walk cache
777 entries for the trampoline before entering the kernel proper.
38fd94b0 778
d9ff80f8
CC
779config QCOM_FALKOR_ERRATUM_1009
780 bool "Falkor E1009: Prematurely complete a DSB after a TLBI"
781 default y
ce8c80c5 782 select ARM64_WORKAROUND_REPEAT_TLBI
d9ff80f8
CC
783 help
784 On Falkor v1, the CPU may prematurely complete a DSB following a
785 TLBI xxIS invalidate maintenance operation. Repeat the TLBI operation
786 one more time to fix the issue.
787
788 If unsure, say Y.
789
90922a2d
SD
790config QCOM_QDF2400_ERRATUM_0065
791 bool "QDF2400 E0065: Incorrect GITS_TYPER.ITT_Entry_size"
792 default y
793 help
794 On Qualcomm Datacenter Technologies QDF2400 SoC, ITS hardware reports
795 ITE size incorrectly. The GITS_TYPER.ITT_Entry_size field should have
796 been indicated as 16Bytes (0xf), not 8Bytes (0x7).
797
798 If unsure, say Y.
799
932b50c7
SD
800config QCOM_FALKOR_ERRATUM_E1041
801 bool "Falkor E1041: Speculative instruction fetches might cause errant memory access"
802 default y
803 help
804 Falkor CPU may speculatively fetch instructions from an improper
805 memory location when MMU translation is changed from SCTLR_ELn[M]=1
806 to SCTLR_ELn[M]=0. Prefix an ISB instruction to fix the problem.
807
808 If unsure, say Y.
809
ebcea694
GU
810config SOCIONEXT_SYNQUACER_PREITS
811 bool "Socionext Synquacer: Workaround for GICv3 pre-ITS"
3e32131a
ZL
812 default y
813 help
ebcea694
GU
814 Socionext Synquacer SoCs implement a separate h/w block to generate
815 MSI doorbell writes with non-zero values for the device ID.
3e32131a
ZL
816
817 If unsure, say Y.
818
c0a01b84
AP
819endmenu
820
821
e41ceed0
JL
822choice
823 prompt "Page size"
824 default ARM64_4K_PAGES
825 help
826 Page size (translation granule) configuration.
827
828config ARM64_4K_PAGES
829 bool "4KB"
830 help
831 This feature enables 4KB pages support.
832
44eaacf1
SP
833config ARM64_16K_PAGES
834 bool "16KB"
835 help
836 The system will use 16KB pages support. AArch32 emulation
837 requires applications compiled with 16K (or a multiple of 16K)
838 aligned segments.
839
8c2c3df3 840config ARM64_64K_PAGES
e41ceed0 841 bool "64KB"
8c2c3df3
CM
842 help
843 This feature enables 64KB pages support (4KB by default)
844 allowing only two levels of page tables and faster TLB
db488be3
SP
845 look-up. AArch32 emulation requires applications compiled
846 with 64K aligned segments.
8c2c3df3 847
e41ceed0
JL
848endchoice
849
850choice
851 prompt "Virtual address space size"
852 default ARM64_VA_BITS_39 if ARM64_4K_PAGES
44eaacf1 853 default ARM64_VA_BITS_47 if ARM64_16K_PAGES
e41ceed0
JL
854 default ARM64_VA_BITS_42 if ARM64_64K_PAGES
855 help
856 Allows choosing one of multiple possible virtual address
857 space sizes. The level of translation table is determined by
858 a combination of page size and virtual address space size.
859
21539939 860config ARM64_VA_BITS_36
56a3f30e 861 bool "36-bit" if EXPERT
21539939
SP
862 depends on ARM64_16K_PAGES
863
e41ceed0
JL
864config ARM64_VA_BITS_39
865 bool "39-bit"
866 depends on ARM64_4K_PAGES
867
868config ARM64_VA_BITS_42
869 bool "42-bit"
870 depends on ARM64_64K_PAGES
871
44eaacf1
SP
872config ARM64_VA_BITS_47
873 bool "47-bit"
874 depends on ARM64_16K_PAGES
875
c79b954b
JL
876config ARM64_VA_BITS_48
877 bool "48-bit"
c79b954b 878
b6d00d47
SC
879config ARM64_VA_BITS_52
880 bool "52-bit"
68d23da4
WD
881 depends on ARM64_64K_PAGES && (ARM64_PAN || !ARM64_SW_TTBR0_PAN)
882 help
883 Enable 52-bit virtual addressing for userspace when explicitly
b6d00d47
SC
884 requested via a hint to mmap(). The kernel will also use 52-bit
885 virtual addresses for its own mappings (provided HW support for
886 this feature is available, otherwise it reverts to 48-bit).
68d23da4
WD
887
888 NOTE: Enabling 52-bit virtual addressing in conjunction with
889 ARMv8.3 Pointer Authentication will result in the PAC being
890 reduced from 7 bits to 3 bits, which may have a significant
891 impact on its susceptibility to brute-force attacks.
892
893 If unsure, select 48-bit virtual addressing instead.
894
e41ceed0
JL
895endchoice
896
68d23da4
WD
897config ARM64_FORCE_52BIT
898 bool "Force 52-bit virtual addresses for userspace"
b6d00d47 899 depends on ARM64_VA_BITS_52 && EXPERT
68d23da4
WD
900 help
901 For systems with 52-bit userspace VAs enabled, the kernel will attempt
902 to maintain compatibility with older software by providing 48-bit VAs
903 unless a hint is supplied to mmap.
904
905 This configuration option disables the 48-bit compatibility logic, and
906 forces all userspace addresses to be 52-bit on HW that supports it. One
907 should only enable this configuration option for stress testing userspace
908 memory management code. If unsure say N here.
909
e41ceed0
JL
910config ARM64_VA_BITS
911 int
21539939 912 default 36 if ARM64_VA_BITS_36
e41ceed0
JL
913 default 39 if ARM64_VA_BITS_39
914 default 42 if ARM64_VA_BITS_42
44eaacf1 915 default 47 if ARM64_VA_BITS_47
b6d00d47
SC
916 default 48 if ARM64_VA_BITS_48
917 default 52 if ARM64_VA_BITS_52
e41ceed0 918
982aa7c5
KM
919choice
920 prompt "Physical address space size"
921 default ARM64_PA_BITS_48
922 help
923 Choose the maximum physical address range that the kernel will
924 support.
925
926config ARM64_PA_BITS_48
927 bool "48-bit"
928
f77d2817
KM
929config ARM64_PA_BITS_52
930 bool "52-bit (ARMv8.2)"
931 depends on ARM64_64K_PAGES
932 depends on ARM64_PAN || !ARM64_SW_TTBR0_PAN
933 help
934 Enable support for a 52-bit physical address space, introduced as
935 part of the ARMv8.2-LPA extension.
936
937 With this enabled, the kernel will also continue to work on CPUs that
938 do not support ARMv8.2-LPA, but with some added memory overhead (and
939 minor performance overhead).
940
982aa7c5
KM
941endchoice
942
943config ARM64_PA_BITS
944 int
945 default 48 if ARM64_PA_BITS_48
f77d2817 946 default 52 if ARM64_PA_BITS_52
982aa7c5 947
d8e85e14
AR
948choice
949 prompt "Endianness"
950 default CPU_LITTLE_ENDIAN
951 help
952 Select the endianness of data accesses performed by the CPU. Userspace
953 applications will need to be compiled and linked for the endianness
954 that is selected here.
955
a872013d
WD
956config CPU_BIG_ENDIAN
957 bool "Build big-endian kernel"
958 help
d8e85e14
AR
959 Say Y if you plan on running a kernel with a big-endian userspace.
960
961config CPU_LITTLE_ENDIAN
962 bool "Build little-endian kernel"
963 help
964 Say Y if you plan on running a kernel with a little-endian userspace.
965 This is usually the case for distributions targeting arm64.
966
967endchoice
a872013d 968
f6e763b9
MB
969config SCHED_MC
970 bool "Multi-core scheduler support"
f6e763b9
MB
971 help
972 Multi-core scheduler support improves the CPU scheduler's decision
973 making when dealing with multi-core CPU chips at a cost of slightly
974 increased overhead in some places. If unsure say N here.
975
976config SCHED_SMT
977 bool "SMT scheduler support"
f6e763b9
MB
978 help
979 Improves the CPU scheduler's decision making when dealing with
980 MultiThreading at a cost of slightly increased overhead in some
981 places. If unsure say N here.
982
8c2c3df3 983config NR_CPUS
62aa9655
GK
984 int "Maximum number of CPUs (2-4096)"
985 range 2 4096
846a415b 986 default "256"
8c2c3df3 987
9327e2c6
MR
988config HOTPLUG_CPU
989 bool "Support for hot-pluggable CPUs"
217d453d 990 select GENERIC_IRQ_MIGRATION
9327e2c6
MR
991 help
992 Say Y here to experiment with turning CPUs off and on. CPUs
993 can be controlled through /sys/devices/system/cpu.
994
1a2db300
GK
995# Common NUMA Features
996config NUMA
4399e6cd 997 bool "NUMA Memory Allocation and Scheduler Support"
0c2a6cce
KW
998 select ACPI_NUMA if ACPI
999 select OF_NUMA
1a2db300 1000 help
4399e6cd 1001 Enable NUMA (Non-Uniform Memory Access) support.
1a2db300
GK
1002
1003 The kernel will try to allocate memory used by a CPU on the
1004 local memory of the CPU and add some more
1005 NUMA awareness to the kernel.
1006
1007config NODES_SHIFT
1008 int "Maximum NUMA Nodes (as a power of 2)"
1009 range 1 10
2a13c13b 1010 default "4"
1a2db300
GK
1011 depends on NEED_MULTIPLE_NODES
1012 help
1013 Specify the maximum number of NUMA Nodes available on the target
1014 system. Increases memory reserved to accommodate various tables.
1015
1016config USE_PERCPU_NUMA_NODE_ID
1017 def_bool y
1018 depends on NUMA
1019
7af3a0a9
ZL
1020config HAVE_SETUP_PER_CPU_AREA
1021 def_bool y
1022 depends on NUMA
1023
1024config NEED_PER_CPU_EMBED_FIRST_CHUNK
1025 def_bool y
1026 depends on NUMA
1027
6d526ee2
AB
1028config HOLES_IN_ZONE
1029 def_bool y
6d526ee2 1030
8636a1f9 1031source "kernel/Kconfig.hz"
8c2c3df3 1032
8c2c3df3
CM
1033config ARCH_SPARSEMEM_ENABLE
1034 def_bool y
1035 select SPARSEMEM_VMEMMAP_ENABLE
1036
1037config ARCH_SPARSEMEM_DEFAULT
1038 def_bool ARCH_SPARSEMEM_ENABLE
1039
1040config ARCH_SELECT_MEMORY_MODEL
1041 def_bool ARCH_SPARSEMEM_ENABLE
1042
e7d4bac4 1043config ARCH_FLATMEM_ENABLE
54501ac1 1044 def_bool !NUMA
e7d4bac4 1045
8c2c3df3 1046config HW_PERF_EVENTS
6475b2d8
MR
1047 def_bool y
1048 depends on ARM_PMU
8c2c3df3 1049
084bd298
SC
1050config SYS_SUPPORTS_HUGETLBFS
1051 def_bool y
1052
084bd298 1053config ARCH_WANT_HUGE_PMD_SHARE
084bd298 1054
a41dc0e8
CM
1055config ARCH_HAS_CACHE_LINE_SIZE
1056 def_bool y
1057
54c8d911
YZ
1058config ARCH_ENABLE_SPLIT_PMD_PTLOCK
1059 def_bool y if PGTABLE_LEVELS > 2
1060
5287569a
ST
1061# Supported by clang >= 7.0
1062config CC_HAVE_SHADOW_CALL_STACK
1063 def_bool $(cc-option, -fsanitize=shadow-call-stack -ffixed-x18)
1064
dfd57bc3
SS
1065config PARAVIRT
1066 bool "Enable paravirtualization code"
1067 help
1068 This changes the kernel so it can modify itself when it is run
1069 under a hypervisor, potentially improving performance significantly
1070 over full virtualization.
1071
1072config PARAVIRT_TIME_ACCOUNTING
1073 bool "Paravirtual steal time accounting"
1074 select PARAVIRT
dfd57bc3
SS
1075 help
1076 Select this option to enable fine granularity task steal time
1077 accounting. Time spent executing other tasks in parallel with
1078 the current vCPU is discounted from the vCPU power. To account for
1079 that, there can be a small performance impact.
1080
1081 If in doubt, say N here.
1082
d28f6df1
GL
1083config KEXEC
1084 depends on PM_SLEEP_SMP
1085 select KEXEC_CORE
1086 bool "kexec system call"
a7f7f624 1087 help
d28f6df1
GL
1088 kexec is a system call that implements the ability to shutdown your
1089 current kernel, and to start another kernel. It is like a reboot
1090 but it is independent of the system firmware. And like a reboot
1091 you can start any kernel with it, not just Linux.
1092
3ddd9992
AT
1093config KEXEC_FILE
1094 bool "kexec file based system call"
1095 select KEXEC_CORE
1096 help
1097 This is new version of kexec system call. This system call is
1098 file based and takes file descriptors as system call argument
1099 for kernel and initramfs as opposed to list of segments as
1100 accepted by previous system call.
1101
99d5cadf 1102config KEXEC_SIG
732b7b93
AT
1103 bool "Verify kernel signature during kexec_file_load() syscall"
1104 depends on KEXEC_FILE
1105 help
1106 Select this option to verify a signature with loaded kernel
1107 image. If configured, any attempt of loading a image without
1108 valid signature will fail.
1109
1110 In addition to that option, you need to enable signature
1111 verification for the corresponding kernel image type being
1112 loaded in order for this to work.
1113
1114config KEXEC_IMAGE_VERIFY_SIG
1115 bool "Enable Image signature verification support"
1116 default y
99d5cadf 1117 depends on KEXEC_SIG
732b7b93
AT
1118 depends on EFI && SIGNED_PE_FILE_VERIFICATION
1119 help
1120 Enable Image signature verification support.
1121
1122comment "Support for PE file signature verification disabled"
99d5cadf 1123 depends on KEXEC_SIG
732b7b93
AT
1124 depends on !EFI || !SIGNED_PE_FILE_VERIFICATION
1125
e62aaeac
AT
1126config CRASH_DUMP
1127 bool "Build kdump crash kernel"
1128 help
1129 Generate crash dump after being started by kexec. This should
1130 be normally only set in special crash dump kernels which are
1131 loaded in the main kernel with kexec-tools into a specially
1132 reserved region and then later executed after a crash by
1133 kdump/kexec.
1134
330d4810 1135 For more details see Documentation/admin-guide/kdump/kdump.rst
e62aaeac 1136
aa42aa13
SS
1137config XEN_DOM0
1138 def_bool y
1139 depends on XEN
1140
1141config XEN
c2ba1f7d 1142 bool "Xen guest support on ARM64"
aa42aa13 1143 depends on ARM64 && OF
83862ccf 1144 select SWIOTLB_XEN
dfd57bc3 1145 select PARAVIRT
aa42aa13
SS
1146 help
1147 Say Y if you want to run Linux in a Virtual Machine on Xen on ARM64.
1148
d03bb145
SC
1149config FORCE_MAX_ZONEORDER
1150 int
1151 default "14" if (ARM64_64K_PAGES && TRANSPARENT_HUGEPAGE)
44eaacf1 1152 default "12" if (ARM64_16K_PAGES && TRANSPARENT_HUGEPAGE)
d03bb145 1153 default "11"
44eaacf1
SP
1154 help
1155 The kernel memory allocator divides physically contiguous memory
1156 blocks into "zones", where each zone is a power of two number of
1157 pages. This option selects the largest power of two that the kernel
1158 keeps in the memory allocator. If you need to allocate very large
1159 blocks of physically contiguous memory, then you may need to
1160 increase this value.
1161
1162 This config option is actually maximum order plus one. For example,
1163 a value of 11 means that the largest free memory block is 2^10 pages.
1164
1165 We make sure that we can allocate upto a HugePage size for each configuration.
1166 Hence we have :
1167 MAX_ORDER = (PMD_SHIFT - PAGE_SHIFT) + 1 => PAGE_SHIFT - 2
1168
1169 However for 4K, we choose a higher default value, 11 as opposed to 10, giving us
1170 4M allocations matching the default size used by generic code.
d03bb145 1171
084eb77c 1172config UNMAP_KERNEL_AT_EL0
0617052d 1173 bool "Unmap kernel when running in userspace (aka \"KAISER\")" if EXPERT
084eb77c
WD
1174 default y
1175 help
0617052d
WD
1176 Speculation attacks against some high-performance processors can
1177 be used to bypass MMU permission checks and leak kernel data to
1178 userspace. This can be defended against by unmapping the kernel
1179 when running in userspace, mapping it back in on exception entry
1180 via a trampoline page in the vector table.
084eb77c
WD
1181
1182 If unsure, say Y.
1183
c55191e9
AB
1184config RODATA_FULL_DEFAULT_ENABLED
1185 bool "Apply r/o permissions of VM areas also to their linear aliases"
1186 default y
1187 help
1188 Apply read-only attributes of VM areas to the linear alias of
1189 the backing pages as well. This prevents code or read-only data
1190 from being modified (inadvertently or intentionally) via another
1191 mapping of the same memory page. This additional enhancement can
1192 be turned off at runtime by passing rodata=[off|on] (and turned on
1193 with rodata=full if this option is set to 'n')
1194
1195 This requires the linear region to be mapped down to pages,
1196 which may adversely affect performance in some cases.
1197
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WD
1198config ARM64_SW_TTBR0_PAN
1199 bool "Emulate Privileged Access Never using TTBR0_EL1 switching"
1200 help
1201 Enabling this option prevents the kernel from accessing
1202 user-space memory directly by pointing TTBR0_EL1 to a reserved
1203 zeroed area and reserved ASID. The user access routines
1204 restore the valid TTBR0_EL1 temporarily.
1205
63f0c603
CM
1206config ARM64_TAGGED_ADDR_ABI
1207 bool "Enable the tagged user addresses syscall ABI"
1208 default y
1209 help
1210 When this option is enabled, user applications can opt in to a
1211 relaxed ABI via prctl() allowing tagged addresses to be passed
1212 to system calls as pointer arguments. For details, see
799c8510 1213 Documentation/arm64/tagged-address-abi.rst.
63f0c603 1214
dd523791
WD
1215menuconfig COMPAT
1216 bool "Kernel support for 32-bit EL0"
1217 depends on ARM64_4K_PAGES || EXPERT
1218 select COMPAT_BINFMT_ELF if BINFMT_ELF
1219 select HAVE_UID16
1220 select OLD_SIGSUSPEND3
1221 select COMPAT_OLD_SIGACTION
1222 help
1223 This option enables support for a 32-bit EL0 running under a 64-bit
1224 kernel at EL1. AArch32-specific components such as system calls,
1225 the user helper functions, VFP support and the ptrace interface are
1226 handled appropriately by the kernel.
1227
1228 If you use a page size other than 4KB (i.e, 16KB or 64KB), please be aware
1229 that you will only be able to execute AArch32 binaries that were compiled
1230 with page size aligned segments.
1231
1232 If you want to execute 32-bit userspace applications, say Y.
1233
1234if COMPAT
1235
1236config KUSER_HELPERS
7c4791c9 1237 bool "Enable kuser helpers page for 32-bit applications"
dd523791
WD
1238 default y
1239 help
1240 Warning: disabling this option may break 32-bit user programs.
1241
1242 Provide kuser helpers to compat tasks. The kernel provides
1243 helper code to userspace in read only form at a fixed location
1244 to allow userspace to be independent of the CPU type fitted to
1245 the system. This permits binaries to be run on ARMv4 through
1246 to ARMv8 without modification.
1247
dc7a12bd 1248 See Documentation/arm/kernel_user_helpers.rst for details.
dd523791
WD
1249
1250 However, the fixed address nature of these helpers can be used
1251 by ROP (return orientated programming) authors when creating
1252 exploits.
1253
1254 If all of the binaries and libraries which run on your platform
1255 are built specifically for your platform, and make no use of
1256 these helpers, then you can turn this option off to hinder
1257 such exploits. However, in that case, if a binary or library
1258 relying on those helpers is run, it will not function correctly.
1259
1260 Say N here only if you are absolutely certain that you do not
1261 need these helpers; otherwise, the safe option is to say Y.
1262
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WD
1263config COMPAT_VDSO
1264 bool "Enable vDSO for 32-bit applications"
1265 depends on !CPU_BIG_ENDIAN && "$(CROSS_COMPILE_COMPAT)" != ""
1266 select GENERIC_COMPAT_VDSO
1267 default y
1268 help
1269 Place in the process address space of 32-bit applications an
1270 ELF shared object providing fast implementations of gettimeofday
1271 and clock_gettime.
1272
1273 You must have a 32-bit build of glibc 2.22 or later for programs
1274 to seamlessly take advantage of this.
dd523791 1275
625412c2
ND
1276config THUMB2_COMPAT_VDSO
1277 bool "Compile the 32-bit vDSO for Thumb-2 mode" if EXPERT
1278 depends on COMPAT_VDSO
1279 default y
1280 help
1281 Compile the compat vDSO with '-mthumb -fomit-frame-pointer' if y,
1282 otherwise with '-marm'.
1283
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WD
1284menuconfig ARMV8_DEPRECATED
1285 bool "Emulate deprecated/obsolete ARMv8 instructions"
6cfa7cc4 1286 depends on SYSCTL
1b907f46
WD
1287 help
1288 Legacy software support may require certain instructions
1289 that have been deprecated or obsoleted in the architecture.
1290
1291 Enable this config to enable selective emulation of these
1292 features.
1293
1294 If unsure, say Y
1295
1296if ARMV8_DEPRECATED
1297
1298config SWP_EMULATION
1299 bool "Emulate SWP/SWPB instructions"
1300 help
1301 ARMv8 obsoletes the use of A32 SWP/SWPB instructions such that
1302 they are always undefined. Say Y here to enable software
1303 emulation of these instructions for userspace using LDXR/STXR.
dd720784
MB
1304 This feature can be controlled at runtime with the abi.swp
1305 sysctl which is disabled by default.
1b907f46
WD
1306
1307 In some older versions of glibc [<=2.8] SWP is used during futex
1308 trylock() operations with the assumption that the code will not
1309 be preempted. This invalid assumption may be more likely to fail
1310 with SWP emulation enabled, leading to deadlock of the user
1311 application.
1312
1313 NOTE: when accessing uncached shared regions, LDXR/STXR rely
1314 on an external transaction monitoring block called a global
1315 monitor to maintain update atomicity. If your system does not
1316 implement a global monitor, this option can cause programs that
1317 perform SWP operations to uncached memory to deadlock.
1318
1319 If unsure, say Y
1320
1321config CP15_BARRIER_EMULATION
1322 bool "Emulate CP15 Barrier instructions"
1323 help
1324 The CP15 barrier instructions - CP15ISB, CP15DSB, and
1325 CP15DMB - are deprecated in ARMv8 (and ARMv7). It is
1326 strongly recommended to use the ISB, DSB, and DMB
1327 instructions instead.
1328
1329 Say Y here to enable software emulation of these
1330 instructions for AArch32 userspace code. When this option is
1331 enabled, CP15 barrier usage is traced which can help
dd720784
MB
1332 identify software that needs updating. This feature can be
1333 controlled at runtime with the abi.cp15_barrier sysctl.
1b907f46
WD
1334
1335 If unsure, say Y
1336
2d888f48
SP
1337config SETEND_EMULATION
1338 bool "Emulate SETEND instruction"
1339 help
1340 The SETEND instruction alters the data-endianness of the
1341 AArch32 EL0, and is deprecated in ARMv8.
1342
1343 Say Y here to enable software emulation of the instruction
dd720784
MB
1344 for AArch32 userspace code. This feature can be controlled
1345 at runtime with the abi.setend sysctl.
2d888f48
SP
1346
1347 Note: All the cpus on the system must have mixed endian support at EL0
1348 for this feature to be enabled. If a new CPU - which doesn't support mixed
1349 endian - is hotplugged in after this feature has been enabled, there could
1350 be unexpected results in the applications.
1351
1352 If unsure, say Y
1b907f46
WD
1353endif
1354
dd523791 1355endif
ba42822a 1356
0e4a0709
WD
1357menu "ARMv8.1 architectural features"
1358
1359config ARM64_HW_AFDBM
1360 bool "Support for hardware updates of the Access and Dirty page flags"
1361 default y
1362 help
1363 The ARMv8.1 architecture extensions introduce support for
1364 hardware updates of the access and dirty information in page
1365 table entries. When enabled in TCR_EL1 (HA and HD bits) on
1366 capable processors, accesses to pages with PTE_AF cleared will
1367 set this bit instead of raising an access flag fault.
1368 Similarly, writes to read-only pages with the DBM bit set will
1369 clear the read-only bit (AP[2]) instead of raising a
1370 permission fault.
1371
1372 Kernels built with this configuration option enabled continue
1373 to work on pre-ARMv8.1 hardware and the performance impact is
1374 minimal. If unsure, say Y.
1375
1376config ARM64_PAN
1377 bool "Enable support for Privileged Access Never (PAN)"
1378 default y
1379 help
1380 Privileged Access Never (PAN; part of the ARMv8.1 Extensions)
1381 prevents the kernel or hypervisor from accessing user-space (EL0)
1382 memory directly.
1383
1384 Choosing this option will cause any unprotected (not using
1385 copy_to_user et al) memory access to fail with a permission fault.
1386
1387 The feature is detected at runtime, and will remain as a 'nop'
1388 instruction if the cpu does not implement the feature.
1389
364a5a8a
WD
1390config AS_HAS_LDAPR
1391 def_bool $(as-instr,.arch_extension rcpc)
1392
0e4a0709 1393config ARM64_LSE_ATOMICS
395af861
CM
1394 bool
1395 default ARM64_USE_LSE_ATOMICS
1396 depends on $(as-instr,.arch_extension lse)
1397
1398config ARM64_USE_LSE_ATOMICS
0e4a0709 1399 bool "Atomic instructions"
b32baf91 1400 depends on JUMP_LABEL
7bd99b40 1401 default y
0e4a0709
WD
1402 help
1403 As part of the Large System Extensions, ARMv8.1 introduces new
1404 atomic instructions that are designed specifically to scale in
1405 very large systems.
1406
1407 Say Y here to make use of these instructions for the in-kernel
1408 atomic routines. This incurs a small overhead on CPUs that do
1409 not support these instructions and requires the kernel to be
7bd99b40
WD
1410 built with binutils >= 2.25 in order for the new instructions
1411 to be used.
0e4a0709 1412
1f364c8c
MZ
1413config ARM64_VHE
1414 bool "Enable support for Virtualization Host Extensions (VHE)"
1415 default y
1416 help
1417 Virtualization Host Extensions (VHE) allow the kernel to run
1418 directly at EL2 (instead of EL1) on processors that support
1419 it. This leads to better performance for KVM, as they reduce
1420 the cost of the world switch.
1421
1422 Selecting this option allows the VHE feature to be detected
1423 at runtime, and does not affect processors that do not
1424 implement this feature.
1425
0e4a0709
WD
1426endmenu
1427
f993318b
WD
1428menu "ARMv8.2 architectural features"
1429
d50e071f
RM
1430config ARM64_PMEM
1431 bool "Enable support for persistent memory"
1432 select ARCH_HAS_PMEM_API
5d7bdeb1 1433 select ARCH_HAS_UACCESS_FLUSHCACHE
d50e071f
RM
1434 help
1435 Say Y to enable support for the persistent memory API based on the
1436 ARMv8.2 DCPoP feature.
1437
1438 The feature is detected at runtime, and the kernel will use DC CVAC
1439 operations if DC CVAP is not supported (following the behaviour of
1440 DC CVAP itself if the system does not define a point of persistence).
1441
64c02720
XX
1442config ARM64_RAS_EXTN
1443 bool "Enable support for RAS CPU Extensions"
1444 default y
1445 help
1446 CPUs that support the Reliability, Availability and Serviceability
1447 (RAS) Extensions, part of ARMv8.2 are able to track faults and
1448 errors, classify them and report them to software.
1449
1450 On CPUs with these extensions system software can use additional
1451 barriers to determine if faults are pending and read the
1452 classification from a new set of registers.
1453
1454 Selecting this feature will allow the kernel to use these barriers
1455 and access the new registers if the system supports the extension.
1456 Platform RAS features may additionally depend on firmware support.
1457
5ffdfaed
VM
1458config ARM64_CNP
1459 bool "Enable support for Common Not Private (CNP) translations"
1460 default y
1461 depends on ARM64_PAN || !ARM64_SW_TTBR0_PAN
1462 help
1463 Common Not Private (CNP) allows translation table entries to
1464 be shared between different PEs in the same inner shareable
1465 domain, so the hardware can use this fact to optimise the
1466 caching of such entries in the TLB.
1467
1468 Selecting this option allows the CNP feature to be detected
1469 at runtime, and does not affect PEs that do not implement
1470 this feature.
1471
f993318b
WD
1472endmenu
1473
04ca3204
MR
1474menu "ARMv8.3 architectural features"
1475
1476config ARM64_PTR_AUTH
1477 bool "Enable support for pointer authentication"
1478 default y
74afda40 1479 depends on (CC_HAS_SIGN_RETURN_ADDRESS || CC_HAS_BRANCH_PROT_PAC_RET) && AS_HAS_PAC
4dc9b282 1480 # Modern compilers insert a .note.gnu.property section note for PAC
15cd0e67 1481 # which is only understood by binutils starting with version 2.33.1.
4dc9b282 1482 depends on LD_IS_LLD || LD_VERSION >= 233010000 || (CC_IS_GCC && GCC_VERSION < 90100)
15cd0e67 1483 depends on !CC_IS_CLANG || AS_HAS_CFI_NEGATE_RA_STATE
74afda40 1484 depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_REGS)
04ca3204
MR
1485 help
1486 Pointer authentication (part of the ARMv8.3 Extensions) provides
1487 instructions for signing and authenticating pointers against secret
1488 keys, which can be used to mitigate Return Oriented Programming (ROP)
1489 and other attacks.
1490
1491 This option enables these instructions at EL0 (i.e. for userspace).
04ca3204
MR
1492 Choosing this option will cause the kernel to initialise secret keys
1493 for each process at exec() time, with these keys being
1494 context-switched along with the process.
1495
74afda40
KM
1496 If the compiler supports the -mbranch-protection or
1497 -msign-return-address flag (e.g. GCC 7 or later), then this option
1498 will also cause the kernel itself to be compiled with return address
1499 protection. In this case, and if the target hardware is known to
1500 support pointer authentication, then CONFIG_STACKPROTECTOR can be
1501 disabled with minimal loss of protection.
1502
04ca3204 1503 The feature is detected at runtime. If the feature is not present in
384b40ca 1504 hardware it will not be advertised to userspace/KVM guest nor will it
dfb0589c 1505 be enabled.
04ca3204 1506
6982934e
KM
1507 If the feature is present on the boot CPU but not on a late CPU, then
1508 the late CPU will be parked. Also, if the boot CPU does not have
1509 address auth and the late CPU has then the late CPU will still boot
1510 but with the feature disabled. On such a system, this option should
1511 not be selected.
1512
74afda40
KM
1513 This feature works with FUNCTION_GRAPH_TRACER option only if
1514 DYNAMIC_FTRACE_WITH_REGS is enabled.
1515
1516config CC_HAS_BRANCH_PROT_PAC_RET
1517 # GCC 9 or later, clang 8 or later
1518 def_bool $(cc-option,-mbranch-protection=pac-ret+leaf)
1519
1520config CC_HAS_SIGN_RETURN_ADDRESS
1521 # GCC 7, 8
1522 def_bool $(cc-option,-msign-return-address=all)
1523
1524config AS_HAS_PAC
4d0831e8 1525 def_bool $(cc-option,-Wa$(comma)-march=armv8.3-a)
74afda40 1526
3b446c7d
ND
1527config AS_HAS_CFI_NEGATE_RA_STATE
1528 def_bool $(as-instr,.cfi_startproc\n.cfi_negate_ra_state\n.cfi_endproc\n)
1529
04ca3204
MR
1530endmenu
1531
2c9d45b4
IV
1532menu "ARMv8.4 architectural features"
1533
1534config ARM64_AMU_EXTN
1535 bool "Enable support for the Activity Monitors Unit CPU extension"
1536 default y
1537 help
1538 The activity monitors extension is an optional extension introduced
1539 by the ARMv8.4 CPU architecture. This enables support for version 1
1540 of the activity monitors architecture, AMUv1.
1541
1542 To enable the use of this extension on CPUs that implement it, say Y.
1543
1544 Note that for architectural reasons, firmware _must_ implement AMU
1545 support when running on CPUs that present the activity monitors
1546 extension. The required support is present in:
1547 * Version 1.5 and later of the ARM Trusted Firmware
1548
1549 For kernels that have this configuration enabled but boot with broken
1550 firmware, you may need to say N here until the firmware is fixed.
1551 Otherwise you may experience firmware panics or lockups when
1552 accessing the counter registers. Even if you are not observing these
1553 symptoms, the values returned by the register reads might not
1554 correctly reflect reality. Most commonly, the value read will be 0,
1555 indicating that the counter is not enabled.
1556
7c78f67e
ZY
1557config AS_HAS_ARMV8_4
1558 def_bool $(cc-option,-Wa$(comma)-march=armv8.4-a)
1559
1560config ARM64_TLB_RANGE
1561 bool "Enable support for tlbi range feature"
1562 default y
1563 depends on AS_HAS_ARMV8_4
1564 help
1565 ARMv8.4-TLBI provides TLBI invalidation instruction that apply to a
1566 range of input addresses.
1567
1568 The feature introduces new assembly instructions, and they were
1569 support when binutils >= 2.30.
1570
04ca3204
MR
1571endmenu
1572
3e6c69a0
MB
1573menu "ARMv8.5 architectural features"
1574
383499f8
DM
1575config ARM64_BTI
1576 bool "Branch Target Identification support"
1577 default y
1578 help
1579 Branch Target Identification (part of the ARMv8.5 Extensions)
1580 provides a mechanism to limit the set of locations to which computed
1581 branch instructions such as BR or BLR can jump.
1582
1583 To make use of BTI on CPUs that support it, say Y.
1584
1585 BTI is intended to provide complementary protection to other control
1586 flow integrity protection mechanisms, such as the Pointer
1587 authentication mechanism provided as part of the ARMv8.3 Extensions.
1588 For this reason, it does not make sense to enable this option without
1589 also enabling support for pointer authentication. Thus, when
1590 enabling this option you should also select ARM64_PTR_AUTH=y.
1591
1592 Userspace binaries must also be specifically compiled to make use of
1593 this mechanism. If you say N here or the hardware does not support
1594 BTI, such binaries can still run, but you get no additional
1595 enforcement of branch destinations.
1596
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MB
1597config ARM64_BTI_KERNEL
1598 bool "Use Branch Target Identification for kernel"
1599 default y
1600 depends on ARM64_BTI
1601 depends on ARM64_PTR_AUTH
1602 depends on CC_HAS_BRANCH_PROT_PAC_RET_BTI
3a88d7c5
WD
1603 # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94697
1604 depends on !CC_IS_GCC || GCC_VERSION >= 100100
97fed779
MB
1605 depends on !(CC_IS_CLANG && GCOV_KERNEL)
1606 depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_REGS)
1607 help
1608 Build the kernel with Branch Target Identification annotations
1609 and enable enforcement of this for kernel code. When this option
1610 is enabled and the system supports BTI all kernel code including
1611 modular code must have BTI enabled.
1612
1613config CC_HAS_BRANCH_PROT_PAC_RET_BTI
1614 # GCC 9 or later, clang 8 or later
1615 def_bool $(cc-option,-mbranch-protection=pac-ret+leaf+bti)
1616
3e6c69a0
MB
1617config ARM64_E0PD
1618 bool "Enable support for E0PD"
1619 default y
1620 help
e717d93b
WD
1621 E0PD (part of the ARMv8.5 extensions) allows us to ensure
1622 that EL0 accesses made via TTBR1 always fault in constant time,
1623 providing similar benefits to KASLR as those provided by KPTI, but
1624 with lower overhead and without disrupting legitimate access to
1625 kernel memory such as SPE.
3e6c69a0 1626
e717d93b 1627 This option enables E0PD for TTBR1 where available.
3e6c69a0 1628
1a50ec0b
RH
1629config ARCH_RANDOM
1630 bool "Enable support for random number generation"
1631 default y
1632 help
1633 Random number generation (part of the ARMv8.5 Extensions)
1634 provides a high bandwidth, cryptographically secure
1635 hardware random number generator.
1636
89b94df9
VF
1637config ARM64_AS_HAS_MTE
1638 # Initial support for MTE went in binutils 2.32.0, checked with
1639 # ".arch armv8.5-a+memtag" below. However, this was incomplete
1640 # as a late addition to the final architecture spec (LDGM/STGM)
1641 # is only supported in the newer 2.32.x and 2.33 binutils
1642 # versions, hence the extra "stgm" instruction check below.
1643 def_bool $(as-instr,.arch armv8.5-a+memtag\nstgm xzr$(comma)[x0])
1644
1645config ARM64_MTE
1646 bool "Memory Tagging Extension support"
1647 default y
1648 depends on ARM64_AS_HAS_MTE && ARM64_TAGGED_ADDR_ABI
1649 select ARCH_USES_HIGH_VMA_FLAGS
1650 help
1651 Memory Tagging (part of the ARMv8.5 Extensions) provides
1652 architectural support for run-time, always-on detection of
1653 various classes of memory error to aid with software debugging
1654 to eliminate vulnerabilities arising from memory-unsafe
1655 languages.
1656
1657 This option enables the support for the Memory Tagging
1658 Extension at EL0 (i.e. for userspace).
1659
1660 Selecting this option allows the feature to be detected at
1661 runtime. Any secondary CPU not implementing this feature will
1662 not be allowed a late bring-up.
1663
1664 Userspace binaries that want to use this feature must
1665 explicitly opt in. The mechanism for the userspace is
1666 described in:
1667
1668 Documentation/arm64/memory-tagging-extension.rst.
1669
3e6c69a0
MB
1670endmenu
1671
ddd25ad1
DM
1672config ARM64_SVE
1673 bool "ARM Scalable Vector Extension support"
1674 default y
85acda3b 1675 depends on !KVM || ARM64_VHE
ddd25ad1
DM
1676 help
1677 The Scalable Vector Extension (SVE) is an extension to the AArch64
1678 execution state which complements and extends the SIMD functionality
1679 of the base architecture to support much larger vectors and to enable
1680 additional vectorisation opportunities.
1681
1682 To enable use of this extension on CPUs that implement it, say Y.
1683
06a916fe
DM
1684 On CPUs that support the SVE2 extensions, this option will enable
1685 those too.
1686
5043694e
DM
1687 Note that for architectural reasons, firmware _must_ implement SVE
1688 support when running on SVE capable hardware. The required support
1689 is present in:
1690
1691 * version 1.5 and later of the ARM Trusted Firmware
1692 * the AArch64 boot wrapper since commit 5e1261e08abf
1693 ("bootwrapper: SVE: Enable SVE for EL2 and below").
1694
1695 For other firmware implementations, consult the firmware documentation
1696 or vendor.
1697
1698 If you need the kernel to boot on SVE-capable hardware with broken
1699 firmware, you may need to say N here until you get your firmware
1700 fixed. Otherwise, you may experience firmware panics or lockups when
1701 booting the kernel. If unsure and you are not observing these
1702 symptoms, you should assume that it is safe to say Y.
fd045f6c 1703
85acda3b
DM
1704 CPUs that support SVE are architecturally required to support the
1705 Virtualization Host Extensions (VHE), so the kernel makes no
1706 provision for supporting SVE alongside KVM without VHE enabled.
1707 Thus, you will need to enable CONFIG_ARM64_VHE if you want to support
1708 KVM in the same kernel image.
1709
fd045f6c 1710config ARM64_MODULE_PLTS
58557e48 1711 bool "Use PLTs to allow module memory to spill over into vmalloc area"
faaa73bc 1712 depends on MODULES
fd045f6c 1713 select HAVE_MOD_ARCH_SPECIFIC
58557e48
FF
1714 help
1715 Allocate PLTs when loading modules so that jumps and calls whose
1716 targets are too far away for their relative offsets to be encoded
1717 in the instructions themselves can be bounced via veneers in the
1718 module's PLT. This allows modules to be allocated in the generic
1719 vmalloc area after the dedicated module memory area has been
1720 exhausted.
1721
1722 When running with address space randomization (KASLR), the module
1723 region itself may be too far away for ordinary relative jumps and
1724 calls, and so in that case, module PLTs are required and cannot be
1725 disabled.
1726
1727 Specific errata workaround(s) might also force module PLTs to be
1728 enabled (ARM64_ERRATUM_843419).
fd045f6c 1729
bc3c03cc
JT
1730config ARM64_PSEUDO_NMI
1731 bool "Support for NMI-like interrupts"
3c9c1dcd 1732 select ARM_GIC_V3
bc3c03cc
JT
1733 help
1734 Adds support for mimicking Non-Maskable Interrupts through the use of
1735 GIC interrupt priority. This support requires version 3 or later of
bc15cf70 1736 ARM GIC.
bc3c03cc
JT
1737
1738 This high priority configuration for interrupts needs to be
1739 explicitly enabled by setting the kernel parameter
1740 "irqchip.gicv3_pseudo_nmi" to 1.
1741
1742 If unsure, say N
1743
48ce8f80
JT
1744if ARM64_PSEUDO_NMI
1745config ARM64_DEBUG_PRIORITY_MASKING
1746 bool "Debug interrupt priority masking"
1747 help
1748 This adds runtime checks to functions enabling/disabling
1749 interrupts when using priority masking. The additional checks verify
1750 the validity of ICC_PMR_EL1 when calling concerned functions.
1751
1752 If unsure, say N
1753endif
1754
1e48ef7f 1755config RELOCATABLE
dd4bc607 1756 bool "Build a relocatable kernel image" if EXPERT
5cf896fb 1757 select ARCH_HAS_RELR
dd4bc607 1758 default y
1e48ef7f
AB
1759 help
1760 This builds the kernel as a Position Independent Executable (PIE),
1761 which retains all relocation metadata required to relocate the
1762 kernel binary at runtime to a different virtual address than the
1763 address it was linked at.
1764 Since AArch64 uses the RELA relocation format, this requires a
1765 relocation pass at runtime even if the kernel is loaded at the
1766 same address it was linked at.
1767
f80fb3a3
AB
1768config RANDOMIZE_BASE
1769 bool "Randomize the address of the kernel image"
b9c220b5 1770 select ARM64_MODULE_PLTS if MODULES
f80fb3a3
AB
1771 select RELOCATABLE
1772 help
1773 Randomizes the virtual address at which the kernel image is
1774 loaded, as a security feature that deters exploit attempts
1775 relying on knowledge of the location of kernel internals.
1776
1777 It is the bootloader's job to provide entropy, by passing a
1778 random u64 value in /chosen/kaslr-seed at kernel entry.
1779
2b5fe07a
AB
1780 When booting via the UEFI stub, it will invoke the firmware's
1781 EFI_RNG_PROTOCOL implementation (if available) to supply entropy
1782 to the kernel proper. In addition, it will randomise the physical
1783 location of the kernel Image as well.
1784
f80fb3a3
AB
1785 If unsure, say N.
1786
1787config RANDOMIZE_MODULE_REGION_FULL
f2b9ba87 1788 bool "Randomize the module region over a 4 GB range"
e71a4e1b 1789 depends on RANDOMIZE_BASE
f80fb3a3
AB
1790 default y
1791 help
f2b9ba87
AB
1792 Randomizes the location of the module region inside a 4 GB window
1793 covering the core kernel. This way, it is less likely for modules
f80fb3a3
AB
1794 to leak information about the location of core kernel data structures
1795 but it does imply that function calls between modules and the core
1796 kernel will need to be resolved via veneers in the module PLT.
1797
1798 When this option is not set, the module region will be randomized over
1799 a limited range that contains the [_stext, _etext] interval of the
1800 core kernel, so branch relocations are always in range.
1801
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AB
1802config CC_HAVE_STACKPROTECTOR_SYSREG
1803 def_bool $(cc-option,-mstack-protector-guard=sysreg -mstack-protector-guard-reg=sp_el0 -mstack-protector-guard-offset=0)
1804
1805config STACKPROTECTOR_PER_TASK
1806 def_bool y
1807 depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_SYSREG
1808
8c2c3df3
CM
1809endmenu
1810
1811menu "Boot options"
1812
5e89c55e
LP
1813config ARM64_ACPI_PARKING_PROTOCOL
1814 bool "Enable support for the ARM64 ACPI parking protocol"
1815 depends on ACPI
1816 help
1817 Enable support for the ARM64 ACPI parking protocol. If disabled
1818 the kernel will not allow booting through the ARM64 ACPI parking
1819 protocol even if the corresponding data is present in the ACPI
1820 MADT table.
1821
8c2c3df3
CM
1822config CMDLINE
1823 string "Default kernel command string"
1824 default ""
1825 help
1826 Provide a set of default command-line options at build time by
1827 entering them here. As a minimum, you should specify the the
1828 root device (e.g. root=/dev/nfs).
1829
1e40d105
TH
1830choice
1831 prompt "Kernel command line type" if CMDLINE != ""
1832 default CMDLINE_FROM_BOOTLOADER
1833 help
1834 Choose how the kernel will handle the provided default kernel
1835 command line string.
1836
1837config CMDLINE_FROM_BOOTLOADER
1838 bool "Use bootloader kernel arguments if available"
1839 help
1840 Uses the command-line options passed by the boot loader. If
1841 the boot loader doesn't provide any, the default kernel command
1842 string provided in CMDLINE will be used.
1843
1844config CMDLINE_EXTEND
1845 bool "Extend bootloader kernel arguments"
1846 help
1847 The command-line arguments provided by the boot loader will be
1848 appended to the default kernel command string.
1849
8c2c3df3
CM
1850config CMDLINE_FORCE
1851 bool "Always use the default kernel command string"
1852 help
1853 Always use the default kernel command string, even if the boot
1854 loader passes other arguments to the kernel.
1855 This is useful if you cannot or don't want to change the
1856 command-line options your boot loader passes to the kernel.
1857
1e40d105
TH
1858endchoice
1859
f4f75ad5
AB
1860config EFI_STUB
1861 bool
1862
f84d0275
MS
1863config EFI
1864 bool "UEFI runtime support"
1865 depends on OF && !CPU_BIG_ENDIAN
b472db6c 1866 depends on KERNEL_MODE_NEON
2c870e61 1867 select ARCH_SUPPORTS_ACPI
f84d0275
MS
1868 select LIBFDT
1869 select UCS2_STRING
1870 select EFI_PARAMS_FROM_FDT
e15dd494 1871 select EFI_RUNTIME_WRAPPERS
f4f75ad5 1872 select EFI_STUB
2e0eb483 1873 select EFI_GENERIC_STUB
f84d0275
MS
1874 default y
1875 help
1876 This option provides support for runtime services provided
1877 by UEFI firmware (such as non-volatile variables, realtime
3c7f2550
MS
1878 clock, and platform reset). A UEFI stub is also provided to
1879 allow the kernel to be booted as an EFI application. This
1880 is only useful on systems that have UEFI firmware.
f84d0275 1881
d1ae8c00
YL
1882config DMI
1883 bool "Enable support for SMBIOS (DMI) tables"
1884 depends on EFI
1885 default y
1886 help
1887 This enables SMBIOS/DMI feature for systems.
1888
1889 This option is only useful on systems that have UEFI firmware.
1890 However, even with this option, the resultant kernel should
1891 continue to boot on existing non-UEFI platforms.
1892
8c2c3df3
CM
1893endmenu
1894
8c2c3df3
CM
1895config SYSVIPC_COMPAT
1896 def_bool y
1897 depends on COMPAT && SYSVIPC
1898
4a03a058
AK
1899config ARCH_ENABLE_HUGEPAGE_MIGRATION
1900 def_bool y
1901 depends on HUGETLB_PAGE && MIGRATION
1902
53fa117b
AK
1903config ARCH_ENABLE_THP_MIGRATION
1904 def_bool y
1905 depends on TRANSPARENT_HUGEPAGE
1906
166936ba
LP
1907menu "Power management options"
1908
1909source "kernel/power/Kconfig"
1910
82869ac5
JM
1911config ARCH_HIBERNATION_POSSIBLE
1912 def_bool y
1913 depends on CPU_PM
1914
1915config ARCH_HIBERNATION_HEADER
1916 def_bool y
1917 depends on HIBERNATION
1918
166936ba
LP
1919config ARCH_SUSPEND_POSSIBLE
1920 def_bool y
1921
166936ba
LP
1922endmenu
1923
1307220d
LP
1924menu "CPU Power Management"
1925
1926source "drivers/cpuidle/Kconfig"
1927
52e7e816
RH
1928source "drivers/cpufreq/Kconfig"
1929
1930endmenu
1931
f84d0275
MS
1932source "drivers/firmware/Kconfig"
1933
b6a02173
GG
1934source "drivers/acpi/Kconfig"
1935
c3eb5b14
MZ
1936source "arch/arm64/kvm/Kconfig"
1937
2c98833a
AB
1938if CRYPTO
1939source "arch/arm64/crypto/Kconfig"
1940endif
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