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8c2c3df3
CM
1config ARM64
2 def_bool y
b6197b93 3 select ACPI_CCA_REQUIRED if ACPI
d8f4f161 4 select ACPI_GENERIC_GSI if ACPI
5f1ae4eb 5 select ACPI_GTDT if ACPI
c6bb8f89 6 select ACPI_IORT if ACPI
6933de0c 7 select ACPI_REDUCED_HARDWARE_ONLY if ACPI
52146173 8 select ACPI_MCFG if (ACPI && PCI)
888125a7 9 select ACPI_SPCR_TABLE if ACPI
0ce82232 10 select ACPI_PPTT if ACPI
1d8f51d4 11 select ARCH_CLOCKSOURCE_DATA
ec6d06ef 12 select ARCH_HAS_DEBUG_VIRTUAL
21266be9 13 select ARCH_HAS_DEVMEM_IS_ALLOWED
886643b7
CH
14 select ARCH_HAS_DMA_COHERENT_TO_PFN
15 select ARCH_HAS_DMA_MMAP_PGPROT
38b04a74 16 select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI
2b68f6ca 17 select ARCH_HAS_ELF_RANDOMIZE
e75bef2a 18 select ARCH_HAS_FAST_MULTIPLIER
6974f0c4 19 select ARCH_HAS_FORTIFY_SOURCE
957e3fac 20 select ARCH_HAS_GCOV_PROFILE_ALL
e1073d1e 21 select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
5e4c7549 22 select ARCH_HAS_KCOV
f1e3a12b 23 select ARCH_HAS_MEMBARRIER_SYNC_CORE
3010a5ea 24 select ARCH_HAS_PTE_SPECIAL
d2852a22 25 select ARCH_HAS_SET_MEMORY
ad21fc4f
LA
26 select ARCH_HAS_STRICT_KERNEL_RWX
27 select ARCH_HAS_STRICT_MODULE_RWX
886643b7
CH
28 select ARCH_HAS_SYNC_DMA_FOR_DEVICE
29 select ARCH_HAS_SYNC_DMA_FOR_CPU
4378a7d4 30 select ARCH_HAS_SYSCALL_WRAPPER
1f85008e 31 select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
396a5d4a 32 select ARCH_HAVE_NMI_SAFE_CMPXCHG
087133ac
WD
33 select ARCH_INLINE_READ_LOCK if !PREEMPT
34 select ARCH_INLINE_READ_LOCK_BH if !PREEMPT
35 select ARCH_INLINE_READ_LOCK_IRQ if !PREEMPT
36 select ARCH_INLINE_READ_LOCK_IRQSAVE if !PREEMPT
37 select ARCH_INLINE_READ_UNLOCK if !PREEMPT
38 select ARCH_INLINE_READ_UNLOCK_BH if !PREEMPT
39 select ARCH_INLINE_READ_UNLOCK_IRQ if !PREEMPT
40 select ARCH_INLINE_READ_UNLOCK_IRQRESTORE if !PREEMPT
41 select ARCH_INLINE_WRITE_LOCK if !PREEMPT
42 select ARCH_INLINE_WRITE_LOCK_BH if !PREEMPT
43 select ARCH_INLINE_WRITE_LOCK_IRQ if !PREEMPT
44 select ARCH_INLINE_WRITE_LOCK_IRQSAVE if !PREEMPT
45 select ARCH_INLINE_WRITE_UNLOCK if !PREEMPT
46 select ARCH_INLINE_WRITE_UNLOCK_BH if !PREEMPT
47 select ARCH_INLINE_WRITE_UNLOCK_IRQ if !PREEMPT
48 select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE if !PREEMPT
5d168964
WD
49 select ARCH_INLINE_SPIN_TRYLOCK if !PREEMPT
50 select ARCH_INLINE_SPIN_TRYLOCK_BH if !PREEMPT
51 select ARCH_INLINE_SPIN_LOCK if !PREEMPT
52 select ARCH_INLINE_SPIN_LOCK_BH if !PREEMPT
53 select ARCH_INLINE_SPIN_LOCK_IRQ if !PREEMPT
54 select ARCH_INLINE_SPIN_LOCK_IRQSAVE if !PREEMPT
55 select ARCH_INLINE_SPIN_UNLOCK if !PREEMPT
56 select ARCH_INLINE_SPIN_UNLOCK_BH if !PREEMPT
57 select ARCH_INLINE_SPIN_UNLOCK_IRQ if !PREEMPT
58 select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE if !PREEMPT
c63c8700 59 select ARCH_USE_CMPXCHG_LOCKREF
087133ac 60 select ARCH_USE_QUEUED_RWLOCKS
c1109047 61 select ARCH_USE_QUEUED_SPINLOCKS
c484f256 62 select ARCH_SUPPORTS_MEMORY_FAILURE
4badad35 63 select ARCH_SUPPORTS_ATOMIC_RMW
f3a53f7b 64 select ARCH_SUPPORTS_INT128 if GCC_VERSION >= 50000 || CC_IS_CLANG
56166230 65 select ARCH_SUPPORTS_NUMA_BALANCING
6212a512 66 select ARCH_WANT_COMPAT_IPC_PARSE_VERSION
b6f35981 67 select ARCH_WANT_FRAME_POINTERS
f0b7f8a4 68 select ARCH_HAS_UBSAN_SANITIZE_ALL
25c92a37 69 select ARM_AMBA
1aee5d7a 70 select ARM_ARCH_TIMER
c4188edc 71 select ARM_GIC
875cbf3e 72 select AUDIT_ARCH_COMPAT_GENERIC
3ee80364 73 select ARM_GIC_V2M if PCI
021f6537 74 select ARM_GIC_V3
3ee80364 75 select ARM_GIC_V3_ITS if PCI
bff60792 76 select ARM_PSCI_FW
adace895 77 select BUILDTIME_EXTABLE_SORT
db2789b5 78 select CLONE_BACKWARDS
7ca2ef33 79 select COMMON_CLK
166936ba 80 select CPU_PM if (SUSPEND || CPU_IDLE)
7481cddf 81 select CRC32
7bc13fd3 82 select DCACHE_WORD_ACCESS
0c3b3171 83 select DMA_DIRECT_REMAP
ef37566c 84 select EDAC_SUPPORT
2f34f173 85 select FRAME_POINTER
d4932f9e 86 select GENERIC_ALLOCATOR
2ef7a295 87 select GENERIC_ARCH_TOPOLOGY
8c2c3df3 88 select GENERIC_CLOCKEVENTS
4b3dc967 89 select GENERIC_CLOCKEVENTS_BROADCAST
3be1a5c4 90 select GENERIC_CPU_AUTOPROBE
bf4b558e 91 select GENERIC_EARLY_IOREMAP
2314ee4d 92 select GENERIC_IDLE_POLL_SETUP
78ae2e1c 93 select GENERIC_IRQ_MULTI_HANDLER
8c2c3df3
CM
94 select GENERIC_IRQ_PROBE
95 select GENERIC_IRQ_SHOW
6544e67b 96 select GENERIC_IRQ_SHOW_LEVEL
cb61f676 97 select GENERIC_PCI_IOMAP
65cd4f6c 98 select GENERIC_SCHED_CLOCK
8c2c3df3 99 select GENERIC_SMP_IDLE_THREAD
12a0ef7b
WD
100 select GENERIC_STRNCPY_FROM_USER
101 select GENERIC_STRNLEN_USER
8c2c3df3 102 select GENERIC_TIME_VSYSCALL
a1ddc74a 103 select HANDLE_DOMAIN_IRQ
8c2c3df3 104 select HARDIRQS_SW_RESEND
eb01d42a 105 select HAVE_PCI
9f9a35a7 106 select HAVE_ACPI_APEI if (ACPI && EFI)
5284e1b4 107 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
875cbf3e 108 select HAVE_ARCH_AUDITSYSCALL
8e7a4cef 109 select HAVE_ARCH_BITREVERSE
324420bf 110 select HAVE_ARCH_HUGE_VMAP
9732cafd 111 select HAVE_ARCH_JUMP_LABEL
c296146c 112 select HAVE_ARCH_JUMP_LABEL_RELATIVE
e17d8025 113 select HAVE_ARCH_KASAN if !(ARM64_16K_PAGES && ARM64_VA_BITS_48)
2d4acb90 114 select HAVE_ARCH_KASAN_SW_TAGS if HAVE_ARCH_KASAN
9529247d 115 select HAVE_ARCH_KGDB
8f0d3aa9
DC
116 select HAVE_ARCH_MMAP_RND_BITS
117 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT
271ca788 118 select HAVE_ARCH_PREL32_RELOCATIONS
a1ae65b2 119 select HAVE_ARCH_SECCOMP_FILTER
0b3e3366 120 select HAVE_ARCH_STACKLEAK
9e8084d3 121 select HAVE_ARCH_THREAD_STRUCT_WHITELIST
8c2c3df3 122 select HAVE_ARCH_TRACEHOOK
8ee70879 123 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
e3067861 124 select HAVE_ARCH_VMAP_STACK
8ee70879 125 select HAVE_ARM_SMCCC
6077776b 126 select HAVE_EBPF_JIT
af64d2aa 127 select HAVE_C_RECORDMCOUNT
5284e1b4 128 select HAVE_CMPXCHG_DOUBLE
95eff6b2 129 select HAVE_CMPXCHG_LOCAL
8ee70879 130 select HAVE_CONTEXT_TRACKING
9b2a60c4 131 select HAVE_DEBUG_BUGVERBOSE
b69ec42b 132 select HAVE_DEBUG_KMEMLEAK
6ac2104d 133 select HAVE_DMA_CONTIGUOUS
bd7d38db 134 select HAVE_DYNAMIC_FTRACE
50afc33a 135 select HAVE_EFFICIENT_UNALIGNED_ACCESS
af64d2aa 136 select HAVE_FTRACE_MCOUNT_RECORD
819e50e2
AT
137 select HAVE_FUNCTION_TRACER
138 select HAVE_FUNCTION_GRAPH_TRACER
6b90bd4b 139 select HAVE_GCC_PLUGINS
8c2c3df3 140 select HAVE_GENERIC_DMA_COHERENT
8c2c3df3 141 select HAVE_HW_BREAKPOINT if PERF_EVENTS
24da208d 142 select HAVE_IRQ_TIME_ACCOUNTING
1a2db300 143 select HAVE_MEMBLOCK_NODE_MAP if NUMA
396a5d4a 144 select HAVE_NMI
55834a77 145 select HAVE_PATA_PLATFORM
8c2c3df3 146 select HAVE_PERF_EVENTS
2ee0d7fd
JP
147 select HAVE_PERF_REGS
148 select HAVE_PERF_USER_STACK_DUMP
0a8ea52c 149 select HAVE_REGS_AND_STACK_ACCESS_API
5e5f6dc1 150 select HAVE_RCU_TABLE_FREE
ace8cb75 151 select HAVE_RCU_TABLE_INVALIDATE
409d5db4 152 select HAVE_RSEQ
d148eac0 153 select HAVE_STACKPROTECTOR
055b1212 154 select HAVE_SYSCALL_TRACEPOINTS
2dd0e8d2 155 select HAVE_KPROBES
cd1ee3b1 156 select HAVE_KRETPROBES
876945db 157 select IOMMU_DMA if IOMMU_SUPPORT
8c2c3df3 158 select IRQ_DOMAIN
e8557d1f 159 select IRQ_FORCED_THREADING
fea2acaa 160 select MODULES_USE_ELF_RELA
667b24d0 161 select MULTI_IRQ_HANDLER
f616ab59 162 select NEED_DMA_MAP_STATE
86596f0a 163 select NEED_SG_DMA_LENGTH
8c2c3df3
CM
164 select OF
165 select OF_EARLY_FLATTREE
9bf14b7c 166 select OF_RESERVED_MEM
2eac9c2d 167 select PCI_DOMAINS_GENERIC if PCI
52146173 168 select PCI_ECAM if (ACPI && PCI)
20f1b79d 169 select PCI_SYSCALL if PCI
aa1e8ec1
CM
170 select POWER_RESET
171 select POWER_SUPPLY
4adcec11 172 select REFCOUNT_FULL
8c2c3df3 173 select SPARSE_IRQ
09230cbc 174 select SWIOTLB
7ac57a89 175 select SYSCTL_EXCEPTION_TRACE
c02433dd 176 select THREAD_INFO_IN_TASK
8c2c3df3
CM
177 help
178 ARM 64-bit (AArch64) Linux support.
179
180config 64BIT
181 def_bool y
182
8c2c3df3
CM
183config MMU
184 def_bool y
185
030c4d24
MR
186config ARM64_PAGE_SHIFT
187 int
188 default 16 if ARM64_64K_PAGES
189 default 14 if ARM64_16K_PAGES
190 default 12
191
192config ARM64_CONT_SHIFT
193 int
194 default 5 if ARM64_64K_PAGES
195 default 7 if ARM64_16K_PAGES
196 default 4
197
8f0d3aa9
DC
198config ARCH_MMAP_RND_BITS_MIN
199 default 14 if ARM64_64K_PAGES
200 default 16 if ARM64_16K_PAGES
201 default 18
202
203# max bits determined by the following formula:
204# VA_BITS - PAGE_SHIFT - 3
205config ARCH_MMAP_RND_BITS_MAX
206 default 19 if ARM64_VA_BITS=36
207 default 24 if ARM64_VA_BITS=39
208 default 27 if ARM64_VA_BITS=42
209 default 30 if ARM64_VA_BITS=47
210 default 29 if ARM64_VA_BITS=48 && ARM64_64K_PAGES
211 default 31 if ARM64_VA_BITS=48 && ARM64_16K_PAGES
212 default 33 if ARM64_VA_BITS=48
213 default 14 if ARM64_64K_PAGES
214 default 16 if ARM64_16K_PAGES
215 default 18
216
217config ARCH_MMAP_RND_COMPAT_BITS_MIN
218 default 7 if ARM64_64K_PAGES
219 default 9 if ARM64_16K_PAGES
220 default 11
221
222config ARCH_MMAP_RND_COMPAT_BITS_MAX
223 default 16
224
ce816fa8 225config NO_IOPORT_MAP
d1e6dc91 226 def_bool y if !PCI
8c2c3df3
CM
227
228config STACKTRACE_SUPPORT
229 def_bool y
230
bf0c4e04
JVS
231config ILLEGAL_POINTER_VALUE
232 hex
233 default 0xdead000000000000
234
8c2c3df3
CM
235config LOCKDEP_SUPPORT
236 def_bool y
237
238config TRACE_IRQFLAGS_SUPPORT
239 def_bool y
240
c209f799 241config RWSEM_XCHGADD_ALGORITHM
8c2c3df3
CM
242 def_bool y
243
9fb7410f
DM
244config GENERIC_BUG
245 def_bool y
246 depends on BUG
247
248config GENERIC_BUG_RELATIVE_POINTERS
249 def_bool y
250 depends on GENERIC_BUG
251
8c2c3df3
CM
252config GENERIC_HWEIGHT
253 def_bool y
254
255config GENERIC_CSUM
256 def_bool y
257
258config GENERIC_CALIBRATE_DELAY
259 def_bool y
260
ad67f5a6 261config ZONE_DMA32
8c2c3df3
CM
262 def_bool y
263
e585513b 264config HAVE_GENERIC_GUP
29e56940
SC
265 def_bool y
266
4ab21506
RM
267config ARCH_ENABLE_MEMORY_HOTPLUG
268 def_bool y
269
4b3dc967
WD
270config SMP
271 def_bool y
272
4cfb3613
AB
273config KERNEL_MODE_NEON
274 def_bool y
275
92cc15fc
RH
276config FIX_EARLYCON_MEM
277 def_bool y
278
9f25e6ad
KS
279config PGTABLE_LEVELS
280 int
21539939 281 default 2 if ARM64_16K_PAGES && ARM64_VA_BITS_36
9f25e6ad 282 default 2 if ARM64_64K_PAGES && ARM64_VA_BITS_42
4d08d20f 283 default 3 if ARM64_64K_PAGES && (ARM64_VA_BITS_48 || ARM64_USER_VA_BITS_52)
9f25e6ad 284 default 3 if ARM64_4K_PAGES && ARM64_VA_BITS_39
44eaacf1
SP
285 default 3 if ARM64_16K_PAGES && ARM64_VA_BITS_47
286 default 4 if !ARM64_64K_PAGES && ARM64_VA_BITS_48
9f25e6ad 287
9842ceae
PA
288config ARCH_SUPPORTS_UPROBES
289 def_bool y
290
8f360948
AB
291config ARCH_PROC_KCORE_TEXT
292 def_bool y
293
6a377491 294source "arch/arm64/Kconfig.platforms"
8c2c3df3 295
8c2c3df3
CM
296menu "Kernel Features"
297
c0a01b84
AP
298menu "ARM errata workarounds via the alternatives framework"
299
c9460dcb
SP
300config ARM64_WORKAROUND_CLEAN_CACHE
301 def_bool n
302
c0a01b84
AP
303config ARM64_ERRATUM_826319
304 bool "Cortex-A53: 826319: System might deadlock if a write cannot complete until read data is accepted"
305 default y
c9460dcb 306 select ARM64_WORKAROUND_CLEAN_CACHE
c0a01b84
AP
307 help
308 This option adds an alternative code sequence to work around ARM
309 erratum 826319 on Cortex-A53 parts up to r0p2 with an AMBA 4 ACE or
310 AXI master interface and an L2 cache.
311
312 If a Cortex-A53 uses an AMBA AXI4 ACE interface to other processors
313 and is unable to accept a certain write via this interface, it will
314 not progress on read data presented on the read data channel and the
315 system can deadlock.
316
317 The workaround promotes data cache clean instructions to
318 data cache clean-and-invalidate.
319 Please note that this does not necessarily enable the workaround,
320 as it depends on the alternative framework, which will only patch
321 the kernel if an affected CPU is detected.
322
323 If unsure, say Y.
324
325config ARM64_ERRATUM_827319
326 bool "Cortex-A53: 827319: Data cache clean instructions might cause overlapping transactions to the interconnect"
327 default y
c9460dcb 328 select ARM64_WORKAROUND_CLEAN_CACHE
c0a01b84
AP
329 help
330 This option adds an alternative code sequence to work around ARM
331 erratum 827319 on Cortex-A53 parts up to r0p2 with an AMBA 5 CHI
332 master interface and an L2 cache.
333
334 Under certain conditions this erratum can cause a clean line eviction
335 to occur at the same time as another transaction to the same address
336 on the AMBA 5 CHI interface, which can cause data corruption if the
337 interconnect reorders the two transactions.
338
339 The workaround promotes data cache clean instructions to
340 data cache clean-and-invalidate.
341 Please note that this does not necessarily enable the workaround,
342 as it depends on the alternative framework, which will only patch
343 the kernel if an affected CPU is detected.
344
345 If unsure, say Y.
346
347config ARM64_ERRATUM_824069
348 bool "Cortex-A53: 824069: Cache line might not be marked as clean after a CleanShared snoop"
349 default y
c9460dcb 350 select ARM64_WORKAROUND_CLEAN_CACHE
c0a01b84
AP
351 help
352 This option adds an alternative code sequence to work around ARM
353 erratum 824069 on Cortex-A53 parts up to r0p2 when it is connected
354 to a coherent interconnect.
355
356 If a Cortex-A53 processor is executing a store or prefetch for
357 write instruction at the same time as a processor in another
358 cluster is executing a cache maintenance operation to the same
359 address, then this erratum might cause a clean cache line to be
360 incorrectly marked as dirty.
361
362 The workaround promotes data cache clean instructions to
363 data cache clean-and-invalidate.
364 Please note that this option does not necessarily enable the
365 workaround, as it depends on the alternative framework, which will
366 only patch the kernel if an affected CPU is detected.
367
368 If unsure, say Y.
369
370config ARM64_ERRATUM_819472
371 bool "Cortex-A53: 819472: Store exclusive instructions might cause data corruption"
372 default y
c9460dcb 373 select ARM64_WORKAROUND_CLEAN_CACHE
c0a01b84
AP
374 help
375 This option adds an alternative code sequence to work around ARM
376 erratum 819472 on Cortex-A53 parts up to r0p1 with an L2 cache
377 present when it is connected to a coherent interconnect.
378
379 If the processor is executing a load and store exclusive sequence at
380 the same time as a processor in another cluster is executing a cache
381 maintenance operation to the same address, then this erratum might
382 cause data corruption.
383
384 The workaround promotes data cache clean instructions to
385 data cache clean-and-invalidate.
386 Please note that this does not necessarily enable the workaround,
387 as it depends on the alternative framework, which will only patch
388 the kernel if an affected CPU is detected.
389
390 If unsure, say Y.
391
392config ARM64_ERRATUM_832075
393 bool "Cortex-A57: 832075: possible deadlock on mixing exclusive memory accesses with device loads"
394 default y
395 help
396 This option adds an alternative code sequence to work around ARM
397 erratum 832075 on Cortex-A57 parts up to r1p2.
398
399 Affected Cortex-A57 parts might deadlock when exclusive load/store
400 instructions to Write-Back memory are mixed with Device loads.
401
402 The workaround is to promote device loads to use Load-Acquire
403 semantics.
404 Please note that this does not necessarily enable the workaround,
498cd5c3
MZ
405 as it depends on the alternative framework, which will only patch
406 the kernel if an affected CPU is detected.
407
408 If unsure, say Y.
409
410config ARM64_ERRATUM_834220
411 bool "Cortex-A57: 834220: Stage 2 translation fault might be incorrectly reported in presence of a Stage 1 fault"
412 depends on KVM
413 default y
414 help
415 This option adds an alternative code sequence to work around ARM
416 erratum 834220 on Cortex-A57 parts up to r1p2.
417
418 Affected Cortex-A57 parts might report a Stage 2 translation
419 fault as the result of a Stage 1 fault for load crossing a
420 page boundary when there is a permission or device memory
421 alignment fault at Stage 1 and a translation fault at Stage 2.
422
423 The workaround is to verify that the Stage 1 translation
424 doesn't generate a fault before handling the Stage 2 fault.
425 Please note that this does not necessarily enable the workaround,
c0a01b84
AP
426 as it depends on the alternative framework, which will only patch
427 the kernel if an affected CPU is detected.
428
429 If unsure, say Y.
430
905e8c5d
WD
431config ARM64_ERRATUM_845719
432 bool "Cortex-A53: 845719: a load might read incorrect data"
433 depends on COMPAT
434 default y
435 help
436 This option adds an alternative code sequence to work around ARM
437 erratum 845719 on Cortex-A53 parts up to r0p4.
438
439 When running a compat (AArch32) userspace on an affected Cortex-A53
440 part, a load at EL0 from a virtual address that matches the bottom 32
441 bits of the virtual address used by a recent load at (AArch64) EL1
442 might return incorrect data.
443
444 The workaround is to write the contextidr_el1 register on exception
445 return to a 32-bit task.
446 Please note that this does not necessarily enable the workaround,
447 as it depends on the alternative framework, which will only patch
448 the kernel if an affected CPU is detected.
449
450 If unsure, say Y.
451
df057cc7
WD
452config ARM64_ERRATUM_843419
453 bool "Cortex-A53: 843419: A load or store might access an incorrect address"
df057cc7 454 default y
a257e025 455 select ARM64_MODULE_PLTS if MODULES
df057cc7 456 help
6ffe9923 457 This option links the kernel with '--fix-cortex-a53-843419' and
a257e025
AB
458 enables PLT support to replace certain ADRP instructions, which can
459 cause subsequent memory accesses to use an incorrect address on
460 Cortex-A53 parts up to r0p4.
df057cc7
WD
461
462 If unsure, say Y.
463
ece1397c
SP
464config ARM64_ERRATUM_1024718
465 bool "Cortex-A55: 1024718: Update of DBM/AP bits without break before make might result in incorrect update"
466 default y
467 help
468 This option adds work around for Arm Cortex-A55 Erratum 1024718.
469
470 Affected Cortex-A55 cores (r0p0, r0p1, r1p0) could cause incorrect
471 update of the hardware dirty bit when the DBM/AP bits are updated
472 without a break-before-make. The work around is to disable the usage
473 of hardware DBM locally on the affected cores. CPUs not affected by
474 erratum will continue to use the feature.
df057cc7
WD
475
476 If unsure, say Y.
477
95b861a4
MZ
478config ARM64_ERRATUM_1188873
479 bool "Cortex-A76: MRC read following MRRC read of specific Generic Timer in AArch32 might give incorrect result"
480 default y
040f3401 481 select ARM_ARCH_TIMER_OOL_WORKAROUND
95b861a4
MZ
482 help
483 This option adds work arounds for ARM Cortex-A76 erratum 1188873
484
485 Affected Cortex-A76 cores (r0p0, r1p0, r2p0) could cause
486 register corruption when accessing the timer registers from
487 AArch32 userspace.
488
489 If unsure, say Y.
490
a457b0f7
MZ
491config ARM64_ERRATUM_1165522
492 bool "Cortex-A76: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
493 default y
494 help
495 This option adds work arounds for ARM Cortex-A76 erratum 1165522
496
497 Affected Cortex-A76 cores (r0p0, r1p0, r2p0) could end-up with
498 corrupted TLBs by speculating an AT instruction during a guest
499 context switch.
500
501 If unsure, say Y.
502
ce8c80c5
CM
503config ARM64_ERRATUM_1286807
504 bool "Cortex-A76: Modification of the translation table for a virtual address might lead to read-after-read ordering violation"
505 default y
506 select ARM64_WORKAROUND_REPEAT_TLBI
507 help
508 This option adds workaround for ARM Cortex-A76 erratum 1286807
509
510 On the affected Cortex-A76 cores (r0p0 to r3p0), if a virtual
511 address for a cacheable mapping of a location is being
512 accessed by a core while another core is remapping the virtual
513 address to a new physical page using the recommended
514 break-before-make sequence, then under very rare circumstances
515 TLBI+DSB completes before a read using the translation being
516 invalidated has been observed by other observers. The
517 workaround repeats the TLBI+DSB operation.
518
519 If unsure, say Y.
520
94100970
RR
521config CAVIUM_ERRATUM_22375
522 bool "Cavium erratum 22375, 24313"
523 default y
524 help
525 Enable workaround for erratum 22375, 24313.
526
527 This implements two gicv3-its errata workarounds for ThunderX. Both
528 with small impact affecting only ITS table allocation.
529
530 erratum 22375: only alloc 8MB table size
531 erratum 24313: ignore memory access type
532
533 The fixes are in ITS initialization and basically ignore memory access
534 type and table size provided by the TYPER and BASER registers.
535
536 If unsure, say Y.
537
fbf8f40e
GK
538config CAVIUM_ERRATUM_23144
539 bool "Cavium erratum 23144: ITS SYNC hang on dual socket system"
540 depends on NUMA
541 default y
542 help
543 ITS SYNC command hang for cross node io and collections/cpu mapping.
544
545 If unsure, say Y.
546
6d4e11c5
RR
547config CAVIUM_ERRATUM_23154
548 bool "Cavium erratum 23154: Access to ICC_IAR1_EL1 is not sync'ed"
549 default y
550 help
551 The gicv3 of ThunderX requires a modified version for
552 reading the IAR status to ensure data synchronization
553 (access to icc_iar1_el1 is not sync'ed before and after).
554
555 If unsure, say Y.
556
104a0c02
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557config CAVIUM_ERRATUM_27456
558 bool "Cavium erratum 27456: Broadcast TLBI instructions may cause icache corruption"
559 default y
560 help
561 On ThunderX T88 pass 1.x through 2.1 parts, broadcast TLBI
562 instructions may cause the icache to become corrupted if it
563 contains data for a non-current ASID. The fix is to
564 invalidate the icache when changing the mm context.
565
566 If unsure, say Y.
567
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568config CAVIUM_ERRATUM_30115
569 bool "Cavium erratum 30115: Guest may disable interrupts in host"
570 default y
571 help
572 On ThunderX T88 pass 1.x through 2.2, T81 pass 1.0 through
573 1.2, and T83 Pass 1.0, KVM guest execution may disable
574 interrupts in host. Trapping both GICv3 group-0 and group-1
575 accesses sidesteps the issue.
576
577 If unsure, say Y.
578
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579config QCOM_FALKOR_ERRATUM_1003
580 bool "Falkor E1003: Incorrect translation due to ASID change"
581 default y
38fd94b0
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582 help
583 On Falkor v1, an incorrect ASID may be cached in the TLB when ASID
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584 and BADDR are changed together in TTBRx_EL1. Since we keep the ASID
585 in TTBR1_EL1, this situation only occurs in the entry trampoline and
586 then only for entries in the walk cache, since the leaf translation
587 is unchanged. Work around the erratum by invalidating the walk cache
588 entries for the trampoline before entering the kernel proper.
38fd94b0 589
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590config ARM64_WORKAROUND_REPEAT_TLBI
591 bool
592 help
593 Enable the repeat TLBI workaround for Falkor erratum 1009 and
594 Cortex-A76 erratum 1286807.
595
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596config QCOM_FALKOR_ERRATUM_1009
597 bool "Falkor E1009: Prematurely complete a DSB after a TLBI"
598 default y
ce8c80c5 599 select ARM64_WORKAROUND_REPEAT_TLBI
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600 help
601 On Falkor v1, the CPU may prematurely complete a DSB following a
602 TLBI xxIS invalidate maintenance operation. Repeat the TLBI operation
603 one more time to fix the issue.
604
605 If unsure, say Y.
606
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607config QCOM_QDF2400_ERRATUM_0065
608 bool "QDF2400 E0065: Incorrect GITS_TYPER.ITT_Entry_size"
609 default y
610 help
611 On Qualcomm Datacenter Technologies QDF2400 SoC, ITS hardware reports
612 ITE size incorrectly. The GITS_TYPER.ITT_Entry_size field should have
613 been indicated as 16Bytes (0xf), not 8Bytes (0x7).
614
615 If unsure, say Y.
616
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617config SOCIONEXT_SYNQUACER_PREITS
618 bool "Socionext Synquacer: Workaround for GICv3 pre-ITS"
619 default y
620 help
621 Socionext Synquacer SoCs implement a separate h/w block to generate
622 MSI doorbell writes with non-zero values for the device ID.
623
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624 If unsure, say Y.
625
626config HISILICON_ERRATUM_161600802
627 bool "Hip07 161600802: Erroneous redistributor VLPI base"
628 default y
629 help
630 The HiSilicon Hip07 SoC usees the wrong redistributor base
631 when issued ITS commands such as VMOVP and VMAPP, and requires
632 a 128kB offset to be applied to the target address in this commands.
633
558b0165 634 If unsure, say Y.
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635
636config QCOM_FALKOR_ERRATUM_E1041
637 bool "Falkor E1041: Speculative instruction fetches might cause errant memory access"
638 default y
639 help
640 Falkor CPU may speculatively fetch instructions from an improper
641 memory location when MMU translation is changed from SCTLR_ELn[M]=1
642 to SCTLR_ELn[M]=0. Prefix an ISB instruction to fix the problem.
643
644 If unsure, say Y.
645
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AP
646endmenu
647
648
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JL
649choice
650 prompt "Page size"
651 default ARM64_4K_PAGES
652 help
653 Page size (translation granule) configuration.
654
655config ARM64_4K_PAGES
656 bool "4KB"
657 help
658 This feature enables 4KB pages support.
659
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SP
660config ARM64_16K_PAGES
661 bool "16KB"
662 help
663 The system will use 16KB pages support. AArch32 emulation
664 requires applications compiled with 16K (or a multiple of 16K)
665 aligned segments.
666
8c2c3df3 667config ARM64_64K_PAGES
e41ceed0 668 bool "64KB"
8c2c3df3
CM
669 help
670 This feature enables 64KB pages support (4KB by default)
671 allowing only two levels of page tables and faster TLB
db488be3
SP
672 look-up. AArch32 emulation requires applications compiled
673 with 64K aligned segments.
8c2c3df3 674
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JL
675endchoice
676
677choice
678 prompt "Virtual address space size"
679 default ARM64_VA_BITS_39 if ARM64_4K_PAGES
44eaacf1 680 default ARM64_VA_BITS_47 if ARM64_16K_PAGES
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JL
681 default ARM64_VA_BITS_42 if ARM64_64K_PAGES
682 help
683 Allows choosing one of multiple possible virtual address
684 space sizes. The level of translation table is determined by
685 a combination of page size and virtual address space size.
686
21539939 687config ARM64_VA_BITS_36
56a3f30e 688 bool "36-bit" if EXPERT
21539939
SP
689 depends on ARM64_16K_PAGES
690
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691config ARM64_VA_BITS_39
692 bool "39-bit"
693 depends on ARM64_4K_PAGES
694
695config ARM64_VA_BITS_42
696 bool "42-bit"
697 depends on ARM64_64K_PAGES
698
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699config ARM64_VA_BITS_47
700 bool "47-bit"
701 depends on ARM64_16K_PAGES
702
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703config ARM64_VA_BITS_48
704 bool "48-bit"
c79b954b 705
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706config ARM64_USER_VA_BITS_52
707 bool "52-bit (user)"
708 depends on ARM64_64K_PAGES && (ARM64_PAN || !ARM64_SW_TTBR0_PAN)
709 help
710 Enable 52-bit virtual addressing for userspace when explicitly
711 requested via a hint to mmap(). The kernel will continue to
712 use 48-bit virtual addresses for its own mappings.
713
714 NOTE: Enabling 52-bit virtual addressing in conjunction with
715 ARMv8.3 Pointer Authentication will result in the PAC being
716 reduced from 7 bits to 3 bits, which may have a significant
717 impact on its susceptibility to brute-force attacks.
718
719 If unsure, select 48-bit virtual addressing instead.
720
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721endchoice
722
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723config ARM64_FORCE_52BIT
724 bool "Force 52-bit virtual addresses for userspace"
725 depends on ARM64_USER_VA_BITS_52 && EXPERT
726 help
727 For systems with 52-bit userspace VAs enabled, the kernel will attempt
728 to maintain compatibility with older software by providing 48-bit VAs
729 unless a hint is supplied to mmap.
730
731 This configuration option disables the 48-bit compatibility logic, and
732 forces all userspace addresses to be 52-bit on HW that supports it. One
733 should only enable this configuration option for stress testing userspace
734 memory management code. If unsure say N here.
735
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736config ARM64_VA_BITS
737 int
21539939 738 default 36 if ARM64_VA_BITS_36
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739 default 39 if ARM64_VA_BITS_39
740 default 42 if ARM64_VA_BITS_42
44eaacf1 741 default 47 if ARM64_VA_BITS_47
68d23da4 742 default 48 if ARM64_VA_BITS_48 || ARM64_USER_VA_BITS_52
e41ceed0 743
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744choice
745 prompt "Physical address space size"
746 default ARM64_PA_BITS_48
747 help
748 Choose the maximum physical address range that the kernel will
749 support.
750
751config ARM64_PA_BITS_48
752 bool "48-bit"
753
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754config ARM64_PA_BITS_52
755 bool "52-bit (ARMv8.2)"
756 depends on ARM64_64K_PAGES
757 depends on ARM64_PAN || !ARM64_SW_TTBR0_PAN
758 help
759 Enable support for a 52-bit physical address space, introduced as
760 part of the ARMv8.2-LPA extension.
761
762 With this enabled, the kernel will also continue to work on CPUs that
763 do not support ARMv8.2-LPA, but with some added memory overhead (and
764 minor performance overhead).
765
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766endchoice
767
768config ARM64_PA_BITS
769 int
770 default 48 if ARM64_PA_BITS_48
f77d2817 771 default 52 if ARM64_PA_BITS_52
982aa7c5 772
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773config CPU_BIG_ENDIAN
774 bool "Build big-endian kernel"
775 help
776 Say Y if you plan on running a kernel in big-endian mode.
777
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778config SCHED_MC
779 bool "Multi-core scheduler support"
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780 help
781 Multi-core scheduler support improves the CPU scheduler's decision
782 making when dealing with multi-core CPU chips at a cost of slightly
783 increased overhead in some places. If unsure say N here.
784
785config SCHED_SMT
786 bool "SMT scheduler support"
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787 help
788 Improves the CPU scheduler's decision making when dealing with
789 MultiThreading at a cost of slightly increased overhead in some
790 places. If unsure say N here.
791
8c2c3df3 792config NR_CPUS
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793 int "Maximum number of CPUs (2-4096)"
794 range 2 4096
15942853 795 # These have to remain sorted largest to smallest
e3672649 796 default "64"
8c2c3df3 797
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798config HOTPLUG_CPU
799 bool "Support for hot-pluggable CPUs"
217d453d 800 select GENERIC_IRQ_MIGRATION
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MR
801 help
802 Say Y here to experiment with turning CPUs off and on. CPUs
803 can be controlled through /sys/devices/system/cpu.
804
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805# Common NUMA Features
806config NUMA
807 bool "Numa Memory Allocation and Scheduler Support"
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KW
808 select ACPI_NUMA if ACPI
809 select OF_NUMA
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810 help
811 Enable NUMA (Non Uniform Memory Access) support.
812
813 The kernel will try to allocate memory used by a CPU on the
814 local memory of the CPU and add some more
815 NUMA awareness to the kernel.
816
817config NODES_SHIFT
818 int "Maximum NUMA Nodes (as a power of 2)"
819 range 1 10
820 default "2"
821 depends on NEED_MULTIPLE_NODES
822 help
823 Specify the maximum number of NUMA Nodes available on the target
824 system. Increases memory reserved to accommodate various tables.
825
826config USE_PERCPU_NUMA_NODE_ID
827 def_bool y
828 depends on NUMA
829
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830config HAVE_SETUP_PER_CPU_AREA
831 def_bool y
832 depends on NUMA
833
834config NEED_PER_CPU_EMBED_FIRST_CHUNK
835 def_bool y
836 depends on NUMA
837
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AB
838config HOLES_IN_ZONE
839 def_bool y
6d526ee2 840
8636a1f9 841source "kernel/Kconfig.hz"
8c2c3df3 842
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LA
843config ARCH_SUPPORTS_DEBUG_PAGEALLOC
844 def_bool y
845
8c2c3df3
CM
846config ARCH_SPARSEMEM_ENABLE
847 def_bool y
848 select SPARSEMEM_VMEMMAP_ENABLE
849
850config ARCH_SPARSEMEM_DEFAULT
851 def_bool ARCH_SPARSEMEM_ENABLE
852
853config ARCH_SELECT_MEMORY_MODEL
854 def_bool ARCH_SPARSEMEM_ENABLE
855
e7d4bac4 856config ARCH_FLATMEM_ENABLE
54501ac1 857 def_bool !NUMA
e7d4bac4 858
8c2c3df3 859config HAVE_ARCH_PFN_VALID
8a695a58 860 def_bool y
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CM
861
862config HW_PERF_EVENTS
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MR
863 def_bool y
864 depends on ARM_PMU
8c2c3df3 865
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SC
866config SYS_SUPPORTS_HUGETLBFS
867 def_bool y
868
084bd298 869config ARCH_WANT_HUGE_PMD_SHARE
21539939 870 def_bool y if ARM64_4K_PAGES || (ARM64_16K_PAGES && !ARM64_VA_BITS_36)
084bd298 871
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CM
872config ARCH_HAS_CACHE_LINE_SIZE
873 def_bool y
874
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875config SECCOMP
876 bool "Enable seccomp to safely compute untrusted bytecode"
877 ---help---
878 This kernel feature is useful for number crunching applications
879 that may need to compute untrusted bytecode during their
880 execution. By using pipes or other transports made available to
881 the process as file descriptors supporting the read/write
882 syscalls, it's possible to isolate those applications in
883 their own address space using seccomp. Once seccomp is
884 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
885 and the task is only allowed to execute a few safe syscalls
886 defined by each seccomp mode.
887
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888config PARAVIRT
889 bool "Enable paravirtualization code"
890 help
891 This changes the kernel so it can modify itself when it is run
892 under a hypervisor, potentially improving performance significantly
893 over full virtualization.
894
895config PARAVIRT_TIME_ACCOUNTING
896 bool "Paravirtual steal time accounting"
897 select PARAVIRT
898 default n
899 help
900 Select this option to enable fine granularity task steal time
901 accounting. Time spent executing other tasks in parallel with
902 the current vCPU is discounted from the vCPU power. To account for
903 that, there can be a small performance impact.
904
905 If in doubt, say N here.
906
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GL
907config KEXEC
908 depends on PM_SLEEP_SMP
909 select KEXEC_CORE
910 bool "kexec system call"
911 ---help---
912 kexec is a system call that implements the ability to shutdown your
913 current kernel, and to start another kernel. It is like a reboot
914 but it is independent of the system firmware. And like a reboot
915 you can start any kernel with it, not just Linux.
916
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AT
917config KEXEC_FILE
918 bool "kexec file based system call"
919 select KEXEC_CORE
920 help
921 This is new version of kexec system call. This system call is
922 file based and takes file descriptors as system call argument
923 for kernel and initramfs as opposed to list of segments as
924 accepted by previous system call.
925
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AT
926config KEXEC_VERIFY_SIG
927 bool "Verify kernel signature during kexec_file_load() syscall"
928 depends on KEXEC_FILE
929 help
930 Select this option to verify a signature with loaded kernel
931 image. If configured, any attempt of loading a image without
932 valid signature will fail.
933
934 In addition to that option, you need to enable signature
935 verification for the corresponding kernel image type being
936 loaded in order for this to work.
937
938config KEXEC_IMAGE_VERIFY_SIG
939 bool "Enable Image signature verification support"
940 default y
941 depends on KEXEC_VERIFY_SIG
942 depends on EFI && SIGNED_PE_FILE_VERIFICATION
943 help
944 Enable Image signature verification support.
945
946comment "Support for PE file signature verification disabled"
947 depends on KEXEC_VERIFY_SIG
948 depends on !EFI || !SIGNED_PE_FILE_VERIFICATION
949
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AT
950config CRASH_DUMP
951 bool "Build kdump crash kernel"
952 help
953 Generate crash dump after being started by kexec. This should
954 be normally only set in special crash dump kernels which are
955 loaded in the main kernel with kexec-tools into a specially
956 reserved region and then later executed after a crash by
957 kdump/kexec.
958
959 For more details see Documentation/kdump/kdump.txt
960
aa42aa13
SS
961config XEN_DOM0
962 def_bool y
963 depends on XEN
964
965config XEN
c2ba1f7d 966 bool "Xen guest support on ARM64"
aa42aa13 967 depends on ARM64 && OF
83862ccf 968 select SWIOTLB_XEN
dfd57bc3 969 select PARAVIRT
aa42aa13
SS
970 help
971 Say Y if you want to run Linux in a Virtual Machine on Xen on ARM64.
972
d03bb145
SC
973config FORCE_MAX_ZONEORDER
974 int
975 default "14" if (ARM64_64K_PAGES && TRANSPARENT_HUGEPAGE)
44eaacf1 976 default "12" if (ARM64_16K_PAGES && TRANSPARENT_HUGEPAGE)
d03bb145 977 default "11"
44eaacf1
SP
978 help
979 The kernel memory allocator divides physically contiguous memory
980 blocks into "zones", where each zone is a power of two number of
981 pages. This option selects the largest power of two that the kernel
982 keeps in the memory allocator. If you need to allocate very large
983 blocks of physically contiguous memory, then you may need to
984 increase this value.
985
986 This config option is actually maximum order plus one. For example,
987 a value of 11 means that the largest free memory block is 2^10 pages.
988
989 We make sure that we can allocate upto a HugePage size for each configuration.
990 Hence we have :
991 MAX_ORDER = (PMD_SHIFT - PAGE_SHIFT) + 1 => PAGE_SHIFT - 2
992
993 However for 4K, we choose a higher default value, 11 as opposed to 10, giving us
994 4M allocations matching the default size used by generic code.
d03bb145 995
084eb77c 996config UNMAP_KERNEL_AT_EL0
0617052d 997 bool "Unmap kernel when running in userspace (aka \"KAISER\")" if EXPERT
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WD
998 default y
999 help
0617052d
WD
1000 Speculation attacks against some high-performance processors can
1001 be used to bypass MMU permission checks and leak kernel data to
1002 userspace. This can be defended against by unmapping the kernel
1003 when running in userspace, mapping it back in on exception entry
1004 via a trampoline page in the vector table.
084eb77c
WD
1005
1006 If unsure, say Y.
1007
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WD
1008config HARDEN_BRANCH_PREDICTOR
1009 bool "Harden the branch predictor against aliasing attacks" if EXPERT
1010 default y
1011 help
1012 Speculation attacks against some high-performance processors rely on
1013 being able to manipulate the branch predictor for a victim context by
1014 executing aliasing branches in the attacker context. Such attacks
1015 can be partially mitigated against by clearing internal branch
1016 predictor state and limiting the prediction logic in some situations.
1017
1018 This config option will take CPU-specific actions to harden the
1019 branch predictor against aliasing attacks and may rely on specific
1020 instruction sequences or control bits being set by the system
1021 firmware.
1022
1023 If unsure, say Y.
1024
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1025config HARDEN_EL2_VECTORS
1026 bool "Harden EL2 vector mapping against system register leak" if EXPERT
1027 default y
1028 help
1029 Speculation attacks against some high-performance processors can
1030 be used to leak privileged information such as the vector base
1031 register, resulting in a potential defeat of the EL2 layout
1032 randomization.
1033
1034 This config option will map the vectors to a fixed location,
1035 independent of the EL2 code mapping, so that revealing VBAR_EL2
1036 to an attacker does not give away any extra information. This
1037 only gets enabled on affected CPUs.
1038
1039 If unsure, say Y.
1040
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MZ
1041config ARM64_SSBD
1042 bool "Speculative Store Bypass Disable" if EXPERT
1043 default y
1044 help
1045 This enables mitigation of the bypassing of previous stores
1046 by speculative loads.
1047
1048 If unsure, say Y.
1049
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AB
1050config RODATA_FULL_DEFAULT_ENABLED
1051 bool "Apply r/o permissions of VM areas also to their linear aliases"
1052 default y
1053 help
1054 Apply read-only attributes of VM areas to the linear alias of
1055 the backing pages as well. This prevents code or read-only data
1056 from being modified (inadvertently or intentionally) via another
1057 mapping of the same memory page. This additional enhancement can
1058 be turned off at runtime by passing rodata=[off|on] (and turned on
1059 with rodata=full if this option is set to 'n')
1060
1061 This requires the linear region to be mapped down to pages,
1062 which may adversely affect performance in some cases.
1063
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WD
1064menuconfig ARMV8_DEPRECATED
1065 bool "Emulate deprecated/obsolete ARMv8 instructions"
1066 depends on COMPAT
6cfa7cc4 1067 depends on SYSCTL
1b907f46
WD
1068 help
1069 Legacy software support may require certain instructions
1070 that have been deprecated or obsoleted in the architecture.
1071
1072 Enable this config to enable selective emulation of these
1073 features.
1074
1075 If unsure, say Y
1076
1077if ARMV8_DEPRECATED
1078
1079config SWP_EMULATION
1080 bool "Emulate SWP/SWPB instructions"
1081 help
1082 ARMv8 obsoletes the use of A32 SWP/SWPB instructions such that
1083 they are always undefined. Say Y here to enable software
1084 emulation of these instructions for userspace using LDXR/STXR.
1085
1086 In some older versions of glibc [<=2.8] SWP is used during futex
1087 trylock() operations with the assumption that the code will not
1088 be preempted. This invalid assumption may be more likely to fail
1089 with SWP emulation enabled, leading to deadlock of the user
1090 application.
1091
1092 NOTE: when accessing uncached shared regions, LDXR/STXR rely
1093 on an external transaction monitoring block called a global
1094 monitor to maintain update atomicity. If your system does not
1095 implement a global monitor, this option can cause programs that
1096 perform SWP operations to uncached memory to deadlock.
1097
1098 If unsure, say Y
1099
1100config CP15_BARRIER_EMULATION
1101 bool "Emulate CP15 Barrier instructions"
1102 help
1103 The CP15 barrier instructions - CP15ISB, CP15DSB, and
1104 CP15DMB - are deprecated in ARMv8 (and ARMv7). It is
1105 strongly recommended to use the ISB, DSB, and DMB
1106 instructions instead.
1107
1108 Say Y here to enable software emulation of these
1109 instructions for AArch32 userspace code. When this option is
1110 enabled, CP15 barrier usage is traced which can help
1111 identify software that needs updating.
1112
1113 If unsure, say Y
1114
2d888f48
SP
1115config SETEND_EMULATION
1116 bool "Emulate SETEND instruction"
1117 help
1118 The SETEND instruction alters the data-endianness of the
1119 AArch32 EL0, and is deprecated in ARMv8.
1120
1121 Say Y here to enable software emulation of the instruction
1122 for AArch32 userspace code.
1123
1124 Note: All the cpus on the system must have mixed endian support at EL0
1125 for this feature to be enabled. If a new CPU - which doesn't support mixed
1126 endian - is hotplugged in after this feature has been enabled, there could
1127 be unexpected results in the applications.
1128
1129 If unsure, say Y
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WD
1130endif
1131
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CM
1132config ARM64_SW_TTBR0_PAN
1133 bool "Emulate Privileged Access Never using TTBR0_EL1 switching"
1134 help
1135 Enabling this option prevents the kernel from accessing
1136 user-space memory directly by pointing TTBR0_EL1 to a reserved
1137 zeroed area and reserved ASID. The user access routines
1138 restore the valid TTBR0_EL1 temporarily.
1139
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WD
1140menu "ARMv8.1 architectural features"
1141
1142config ARM64_HW_AFDBM
1143 bool "Support for hardware updates of the Access and Dirty page flags"
1144 default y
1145 help
1146 The ARMv8.1 architecture extensions introduce support for
1147 hardware updates of the access and dirty information in page
1148 table entries. When enabled in TCR_EL1 (HA and HD bits) on
1149 capable processors, accesses to pages with PTE_AF cleared will
1150 set this bit instead of raising an access flag fault.
1151 Similarly, writes to read-only pages with the DBM bit set will
1152 clear the read-only bit (AP[2]) instead of raising a
1153 permission fault.
1154
1155 Kernels built with this configuration option enabled continue
1156 to work on pre-ARMv8.1 hardware and the performance impact is
1157 minimal. If unsure, say Y.
1158
1159config ARM64_PAN
1160 bool "Enable support for Privileged Access Never (PAN)"
1161 default y
1162 help
1163 Privileged Access Never (PAN; part of the ARMv8.1 Extensions)
1164 prevents the kernel or hypervisor from accessing user-space (EL0)
1165 memory directly.
1166
1167 Choosing this option will cause any unprotected (not using
1168 copy_to_user et al) memory access to fail with a permission fault.
1169
1170 The feature is detected at runtime, and will remain as a 'nop'
1171 instruction if the cpu does not implement the feature.
1172
1173config ARM64_LSE_ATOMICS
1174 bool "Atomic instructions"
7bd99b40 1175 default y
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WD
1176 help
1177 As part of the Large System Extensions, ARMv8.1 introduces new
1178 atomic instructions that are designed specifically to scale in
1179 very large systems.
1180
1181 Say Y here to make use of these instructions for the in-kernel
1182 atomic routines. This incurs a small overhead on CPUs that do
1183 not support these instructions and requires the kernel to be
7bd99b40
WD
1184 built with binutils >= 2.25 in order for the new instructions
1185 to be used.
0e4a0709 1186
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MZ
1187config ARM64_VHE
1188 bool "Enable support for Virtualization Host Extensions (VHE)"
1189 default y
1190 help
1191 Virtualization Host Extensions (VHE) allow the kernel to run
1192 directly at EL2 (instead of EL1) on processors that support
1193 it. This leads to better performance for KVM, as they reduce
1194 the cost of the world switch.
1195
1196 Selecting this option allows the VHE feature to be detected
1197 at runtime, and does not affect processors that do not
1198 implement this feature.
1199
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1200endmenu
1201
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1202menu "ARMv8.2 architectural features"
1203
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JM
1204config ARM64_UAO
1205 bool "Enable support for User Access Override (UAO)"
1206 default y
1207 help
1208 User Access Override (UAO; part of the ARMv8.2 Extensions)
1209 causes the 'unprivileged' variant of the load/store instructions to
83fc61a5 1210 be overridden to be privileged.
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JM
1211
1212 This option changes get_user() and friends to use the 'unprivileged'
1213 variant of the load/store instructions. This ensures that user-space
1214 really did have access to the supplied memory. When addr_limit is
1215 set to kernel memory the UAO bit will be set, allowing privileged
1216 access to kernel memory.
1217
1218 Choosing this option will cause copy_to_user() et al to use user-space
1219 memory permissions.
1220
1221 The feature is detected at runtime, the kernel will use the
1222 regular load/store instructions if the cpu does not implement the
1223 feature.
1224
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RM
1225config ARM64_PMEM
1226 bool "Enable support for persistent memory"
1227 select ARCH_HAS_PMEM_API
5d7bdeb1 1228 select ARCH_HAS_UACCESS_FLUSHCACHE
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RM
1229 help
1230 Say Y to enable support for the persistent memory API based on the
1231 ARMv8.2 DCPoP feature.
1232
1233 The feature is detected at runtime, and the kernel will use DC CVAC
1234 operations if DC CVAP is not supported (following the behaviour of
1235 DC CVAP itself if the system does not define a point of persistence).
1236
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1237config ARM64_RAS_EXTN
1238 bool "Enable support for RAS CPU Extensions"
1239 default y
1240 help
1241 CPUs that support the Reliability, Availability and Serviceability
1242 (RAS) Extensions, part of ARMv8.2 are able to track faults and
1243 errors, classify them and report them to software.
1244
1245 On CPUs with these extensions system software can use additional
1246 barriers to determine if faults are pending and read the
1247 classification from a new set of registers.
1248
1249 Selecting this feature will allow the kernel to use these barriers
1250 and access the new registers if the system supports the extension.
1251 Platform RAS features may additionally depend on firmware support.
1252
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VM
1253config ARM64_CNP
1254 bool "Enable support for Common Not Private (CNP) translations"
1255 default y
1256 depends on ARM64_PAN || !ARM64_SW_TTBR0_PAN
1257 help
1258 Common Not Private (CNP) allows translation table entries to
1259 be shared between different PEs in the same inner shareable
1260 domain, so the hardware can use this fact to optimise the
1261 caching of such entries in the TLB.
1262
1263 Selecting this option allows the CNP feature to be detected
1264 at runtime, and does not affect PEs that do not implement
1265 this feature.
1266
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1267endmenu
1268
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1269menu "ARMv8.3 architectural features"
1270
1271config ARM64_PTR_AUTH
1272 bool "Enable support for pointer authentication"
1273 default y
1274 help
1275 Pointer authentication (part of the ARMv8.3 Extensions) provides
1276 instructions for signing and authenticating pointers against secret
1277 keys, which can be used to mitigate Return Oriented Programming (ROP)
1278 and other attacks.
1279
1280 This option enables these instructions at EL0 (i.e. for userspace).
1281
1282 Choosing this option will cause the kernel to initialise secret keys
1283 for each process at exec() time, with these keys being
1284 context-switched along with the process.
1285
1286 The feature is detected at runtime. If the feature is not present in
1287 hardware it will not be advertised to userspace nor will it be
1288 enabled.
1289
1290endmenu
1291
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DM
1292config ARM64_SVE
1293 bool "ARM Scalable Vector Extension support"
1294 default y
85acda3b 1295 depends on !KVM || ARM64_VHE
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1296 help
1297 The Scalable Vector Extension (SVE) is an extension to the AArch64
1298 execution state which complements and extends the SIMD functionality
1299 of the base architecture to support much larger vectors and to enable
1300 additional vectorisation opportunities.
1301
1302 To enable use of this extension on CPUs that implement it, say Y.
1303
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1304 Note that for architectural reasons, firmware _must_ implement SVE
1305 support when running on SVE capable hardware. The required support
1306 is present in:
1307
1308 * version 1.5 and later of the ARM Trusted Firmware
1309 * the AArch64 boot wrapper since commit 5e1261e08abf
1310 ("bootwrapper: SVE: Enable SVE for EL2 and below").
1311
1312 For other firmware implementations, consult the firmware documentation
1313 or vendor.
1314
1315 If you need the kernel to boot on SVE-capable hardware with broken
1316 firmware, you may need to say N here until you get your firmware
1317 fixed. Otherwise, you may experience firmware panics or lockups when
1318 booting the kernel. If unsure and you are not observing these
1319 symptoms, you should assume that it is safe to say Y.
fd045f6c 1320
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1321 CPUs that support SVE are architecturally required to support the
1322 Virtualization Host Extensions (VHE), so the kernel makes no
1323 provision for supporting SVE alongside KVM without VHE enabled.
1324 Thus, you will need to enable CONFIG_ARM64_VHE if you want to support
1325 KVM in the same kernel image.
1326
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AB
1327config ARM64_MODULE_PLTS
1328 bool
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AB
1329 select HAVE_MOD_ARCH_SPECIFIC
1330
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AB
1331config RELOCATABLE
1332 bool
1333 help
1334 This builds the kernel as a Position Independent Executable (PIE),
1335 which retains all relocation metadata required to relocate the
1336 kernel binary at runtime to a different virtual address than the
1337 address it was linked at.
1338 Since AArch64 uses the RELA relocation format, this requires a
1339 relocation pass at runtime even if the kernel is loaded at the
1340 same address it was linked at.
1341
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AB
1342config RANDOMIZE_BASE
1343 bool "Randomize the address of the kernel image"
b9c220b5 1344 select ARM64_MODULE_PLTS if MODULES
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AB
1345 select RELOCATABLE
1346 help
1347 Randomizes the virtual address at which the kernel image is
1348 loaded, as a security feature that deters exploit attempts
1349 relying on knowledge of the location of kernel internals.
1350
1351 It is the bootloader's job to provide entropy, by passing a
1352 random u64 value in /chosen/kaslr-seed at kernel entry.
1353
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1354 When booting via the UEFI stub, it will invoke the firmware's
1355 EFI_RNG_PROTOCOL implementation (if available) to supply entropy
1356 to the kernel proper. In addition, it will randomise the physical
1357 location of the kernel Image as well.
1358
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1359 If unsure, say N.
1360
1361config RANDOMIZE_MODULE_REGION_FULL
f2b9ba87 1362 bool "Randomize the module region over a 4 GB range"
e71a4e1b 1363 depends on RANDOMIZE_BASE
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AB
1364 default y
1365 help
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AB
1366 Randomizes the location of the module region inside a 4 GB window
1367 covering the core kernel. This way, it is less likely for modules
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1368 to leak information about the location of core kernel data structures
1369 but it does imply that function calls between modules and the core
1370 kernel will need to be resolved via veneers in the module PLT.
1371
1372 When this option is not set, the module region will be randomized over
1373 a limited range that contains the [_stext, _etext] interval of the
1374 core kernel, so branch relocations are always in range.
1375
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1376config CC_HAVE_STACKPROTECTOR_SYSREG
1377 def_bool $(cc-option,-mstack-protector-guard=sysreg -mstack-protector-guard-reg=sp_el0 -mstack-protector-guard-offset=0)
1378
1379config STACKPROTECTOR_PER_TASK
1380 def_bool y
1381 depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_SYSREG
1382
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1383endmenu
1384
1385menu "Boot options"
1386
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1387config ARM64_ACPI_PARKING_PROTOCOL
1388 bool "Enable support for the ARM64 ACPI parking protocol"
1389 depends on ACPI
1390 help
1391 Enable support for the ARM64 ACPI parking protocol. If disabled
1392 the kernel will not allow booting through the ARM64 ACPI parking
1393 protocol even if the corresponding data is present in the ACPI
1394 MADT table.
1395
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CM
1396config CMDLINE
1397 string "Default kernel command string"
1398 default ""
1399 help
1400 Provide a set of default command-line options at build time by
1401 entering them here. As a minimum, you should specify the the
1402 root device (e.g. root=/dev/nfs).
1403
1404config CMDLINE_FORCE
1405 bool "Always use the default kernel command string"
1406 help
1407 Always use the default kernel command string, even if the boot
1408 loader passes other arguments to the kernel.
1409 This is useful if you cannot or don't want to change the
1410 command-line options your boot loader passes to the kernel.
1411
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1412config EFI_STUB
1413 bool
1414
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MS
1415config EFI
1416 bool "UEFI runtime support"
1417 depends on OF && !CPU_BIG_ENDIAN
b472db6c 1418 depends on KERNEL_MODE_NEON
2c870e61 1419 select ARCH_SUPPORTS_ACPI
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MS
1420 select LIBFDT
1421 select UCS2_STRING
1422 select EFI_PARAMS_FROM_FDT
e15dd494 1423 select EFI_RUNTIME_WRAPPERS
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AB
1424 select EFI_STUB
1425 select EFI_ARMSTUB
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MS
1426 default y
1427 help
1428 This option provides support for runtime services provided
1429 by UEFI firmware (such as non-volatile variables, realtime
3c7f2550
MS
1430 clock, and platform reset). A UEFI stub is also provided to
1431 allow the kernel to be booted as an EFI application. This
1432 is only useful on systems that have UEFI firmware.
f84d0275 1433
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YL
1434config DMI
1435 bool "Enable support for SMBIOS (DMI) tables"
1436 depends on EFI
1437 default y
1438 help
1439 This enables SMBIOS/DMI feature for systems.
1440
1441 This option is only useful on systems that have UEFI firmware.
1442 However, even with this option, the resultant kernel should
1443 continue to boot on existing non-UEFI platforms.
1444
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CM
1445endmenu
1446
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CM
1447config COMPAT
1448 bool "Kernel support for 32-bit EL0"
755e70b7 1449 depends on ARM64_4K_PAGES || EXPERT
2e449048 1450 select COMPAT_BINFMT_ELF if BINFMT_ELF
af1839eb 1451 select HAVE_UID16
84b9e9b4 1452 select OLD_SIGSUSPEND3
51682036 1453 select COMPAT_OLD_SIGACTION
8c2c3df3
CM
1454 help
1455 This option enables support for a 32-bit EL0 running under a 64-bit
1456 kernel at EL1. AArch32-specific components such as system calls,
1457 the user helper functions, VFP support and the ptrace interface are
1458 handled appropriately by the kernel.
1459
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SP
1460 If you use a page size other than 4KB (i.e, 16KB or 64KB), please be aware
1461 that you will only be able to execute AArch32 binaries that were compiled
1462 with page size aligned segments.
a8fcd8b1 1463
8c2c3df3
CM
1464 If you want to execute 32-bit userspace applications, say Y.
1465
1466config SYSVIPC_COMPAT
1467 def_bool y
1468 depends on COMPAT && SYSVIPC
1469
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LP
1470menu "Power management options"
1471
1472source "kernel/power/Kconfig"
1473
82869ac5
JM
1474config ARCH_HIBERNATION_POSSIBLE
1475 def_bool y
1476 depends on CPU_PM
1477
1478config ARCH_HIBERNATION_HEADER
1479 def_bool y
1480 depends on HIBERNATION
1481
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LP
1482config ARCH_SUSPEND_POSSIBLE
1483 def_bool y
1484
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LP
1485endmenu
1486
1307220d
LP
1487menu "CPU Power Management"
1488
1489source "drivers/cpuidle/Kconfig"
1490
52e7e816
RH
1491source "drivers/cpufreq/Kconfig"
1492
1493endmenu
1494
f84d0275
MS
1495source "drivers/firmware/Kconfig"
1496
b6a02173
GG
1497source "drivers/acpi/Kconfig"
1498
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MZ
1499source "arch/arm64/kvm/Kconfig"
1500
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AB
1501if CRYPTO
1502source "arch/arm64/crypto/Kconfig"
1503endif