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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
1e866974 14 select ARCH_ENABLE_HUGEPAGE_MIGRATION if HUGETLB_PAGE && MIGRATION
91024b3c
AK
15 select ARCH_ENABLE_MEMORY_HOTPLUG
16 select ARCH_ENABLE_MEMORY_HOTREMOVE
66f24fa7 17 select ARCH_ENABLE_SPLIT_PMD_PTLOCK if PGTABLE_LEVELS > 2
1e866974 18 select ARCH_ENABLE_THP_MIGRATION if TRANSPARENT_HUGEPAGE
c2280be8 19 select ARCH_HAS_CACHE_LINE_SIZE
ec6d06ef 20 select ARCH_HAS_DEBUG_VIRTUAL
399145f9 21 select ARCH_HAS_DEBUG_VM_PGTABLE
13bf5ced 22 select ARCH_HAS_DMA_PREP_COHERENT
38b04a74 23 select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI
e75bef2a 24 select ARCH_HAS_FAST_MULTIPLIER
6974f0c4 25 select ARCH_HAS_FORTIFY_SOURCE
957e3fac 26 select ARCH_HAS_GCOV_PROFILE_ALL
4eb0716e 27 select ARCH_HAS_GIGANTIC_PAGE
5e4c7549 28 select ARCH_HAS_KCOV
d8ae8a37 29 select ARCH_HAS_KEEPINITRD
f1e3a12b 30 select ARCH_HAS_MEMBARRIER_SYNC_CORE
0ebeea8c 31 select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
73b20c84 32 select ARCH_HAS_PTE_DEVMAP
3010a5ea 33 select ARCH_HAS_PTE_SPECIAL
347cb6af 34 select ARCH_HAS_SETUP_DMA_OPS
4739d53f 35 select ARCH_HAS_SET_DIRECT_MAP
d2852a22 36 select ARCH_HAS_SET_MEMORY
5fc57df2 37 select ARCH_STACKWALK
ad21fc4f
LA
38 select ARCH_HAS_STRICT_KERNEL_RWX
39 select ARCH_HAS_STRICT_MODULE_RWX
886643b7
CH
40 select ARCH_HAS_SYNC_DMA_FOR_DEVICE
41 select ARCH_HAS_SYNC_DMA_FOR_CPU
4378a7d4 42 select ARCH_HAS_SYSCALL_WRAPPER
dc2acded 43 select ARCH_HAS_TEARDOWN_DMA_OPS if IOMMU_SUPPORT
1f85008e 44 select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
63703f37 45 select ARCH_HAS_ZONE_DMA_SET if EXPERT
ab7876a9 46 select ARCH_HAVE_ELF_PROT
396a5d4a 47 select ARCH_HAVE_NMI_SAFE_CMPXCHG
7ef858da
TG
48 select ARCH_INLINE_READ_LOCK if !PREEMPTION
49 select ARCH_INLINE_READ_LOCK_BH if !PREEMPTION
50 select ARCH_INLINE_READ_LOCK_IRQ if !PREEMPTION
51 select ARCH_INLINE_READ_LOCK_IRQSAVE if !PREEMPTION
52 select ARCH_INLINE_READ_UNLOCK if !PREEMPTION
53 select ARCH_INLINE_READ_UNLOCK_BH if !PREEMPTION
54 select ARCH_INLINE_READ_UNLOCK_IRQ if !PREEMPTION
55 select ARCH_INLINE_READ_UNLOCK_IRQRESTORE if !PREEMPTION
56 select ARCH_INLINE_WRITE_LOCK if !PREEMPTION
57 select ARCH_INLINE_WRITE_LOCK_BH if !PREEMPTION
58 select ARCH_INLINE_WRITE_LOCK_IRQ if !PREEMPTION
59 select ARCH_INLINE_WRITE_LOCK_IRQSAVE if !PREEMPTION
60 select ARCH_INLINE_WRITE_UNLOCK if !PREEMPTION
61 select ARCH_INLINE_WRITE_UNLOCK_BH if !PREEMPTION
62 select ARCH_INLINE_WRITE_UNLOCK_IRQ if !PREEMPTION
63 select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE if !PREEMPTION
64 select ARCH_INLINE_SPIN_TRYLOCK if !PREEMPTION
65 select ARCH_INLINE_SPIN_TRYLOCK_BH if !PREEMPTION
66 select ARCH_INLINE_SPIN_LOCK if !PREEMPTION
67 select ARCH_INLINE_SPIN_LOCK_BH if !PREEMPTION
68 select ARCH_INLINE_SPIN_LOCK_IRQ if !PREEMPTION
69 select ARCH_INLINE_SPIN_LOCK_IRQSAVE if !PREEMPTION
70 select ARCH_INLINE_SPIN_UNLOCK if !PREEMPTION
71 select ARCH_INLINE_SPIN_UNLOCK_BH if !PREEMPTION
72 select ARCH_INLINE_SPIN_UNLOCK_IRQ if !PREEMPTION
73 select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE if !PREEMPTION
350e88ba 74 select ARCH_KEEP_MEMBLOCK
c63c8700 75 select ARCH_USE_CMPXCHG_LOCKREF
bf7f15c5 76 select ARCH_USE_GNU_PROPERTY
dce44566 77 select ARCH_USE_MEMTEST
087133ac 78 select ARCH_USE_QUEUED_RWLOCKS
c1109047 79 select ARCH_USE_QUEUED_SPINLOCKS
50479d58 80 select ARCH_USE_SYM_ANNOTATIONS
5d6ad668 81 select ARCH_SUPPORTS_DEBUG_PAGEALLOC
855f9a8e 82 select ARCH_SUPPORTS_HUGETLBFS
c484f256 83 select ARCH_SUPPORTS_MEMORY_FAILURE
5287569a 84 select ARCH_SUPPORTS_SHADOW_CALL_STACK if CC_HAVE_SHADOW_CALL_STACK
112b6a8e
ST
85 select ARCH_SUPPORTS_LTO_CLANG if CPU_LITTLE_ENDIAN
86 select ARCH_SUPPORTS_LTO_CLANG_THIN
9186ad8e 87 select ARCH_SUPPORTS_CFI_CLANG
4badad35 88 select ARCH_SUPPORTS_ATOMIC_RMW
42a7ba16 89 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
56166230 90 select ARCH_SUPPORTS_NUMA_BALANCING
84c187af 91 select ARCH_WANT_COMPAT_IPC_PARSE_VERSION if COMPAT
81c22041 92 select ARCH_WANT_DEFAULT_BPF_JIT
67f3977f 93 select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT
b6f35981 94 select ARCH_WANT_FRAME_POINTERS
3876d4a3 95 select ARCH_WANT_HUGE_PMD_SHARE if ARM64_4K_PAGES || (ARM64_16K_PAGES && !ARM64_VA_BITS_36)
59612b24 96 select ARCH_WANT_LD_ORPHAN_WARN
51c2ee6d 97 select ARCH_WANTS_NO_INSTR
f0b7f8a4 98 select ARCH_HAS_UBSAN_SANITIZE_ALL
25c92a37 99 select ARM_AMBA
1aee5d7a 100 select ARM_ARCH_TIMER
c4188edc 101 select ARM_GIC
875cbf3e 102 select AUDIT_ARCH_COMPAT_GENERIC
3ee80364 103 select ARM_GIC_V2M if PCI
021f6537 104 select ARM_GIC_V3
3ee80364 105 select ARM_GIC_V3_ITS if PCI
bff60792 106 select ARM_PSCI_FW
10916706 107 select BUILDTIME_TABLE_SORT
db2789b5 108 select CLONE_BACKWARDS
7ca2ef33 109 select COMMON_CLK
166936ba 110 select CPU_PM if (SUSPEND || CPU_IDLE)
7481cddf 111 select CRC32
7bc13fd3 112 select DCACHE_WORD_ACCESS
0c3b3171 113 select DMA_DIRECT_REMAP
ef37566c 114 select EDAC_SUPPORT
2f34f173 115 select FRAME_POINTER
d4932f9e 116 select GENERIC_ALLOCATOR
2ef7a295 117 select GENERIC_ARCH_TOPOLOGY
4b3dc967 118 select GENERIC_CLOCKEVENTS_BROADCAST
3be1a5c4 119 select GENERIC_CPU_AUTOPROBE
61ae1321 120 select GENERIC_CPU_VULNERABILITIES
bf4b558e 121 select GENERIC_EARLY_IOREMAP
98c5ec77 122 select GENERIC_FIND_FIRST_BIT
2314ee4d 123 select GENERIC_IDLE_POLL_SETUP
d3afc7f1 124 select GENERIC_IRQ_IPI
8c2c3df3
CM
125 select GENERIC_IRQ_PROBE
126 select GENERIC_IRQ_SHOW
6544e67b 127 select GENERIC_IRQ_SHOW_LEVEL
6585bd82 128 select GENERIC_LIB_DEVMEM_IS_ALLOWED
cb61f676 129 select GENERIC_PCI_IOMAP
102f45fd 130 select GENERIC_PTDUMP
65cd4f6c 131 select GENERIC_SCHED_CLOCK
8c2c3df3
CM
132 select GENERIC_SMP_IDLE_THREAD
133 select GENERIC_TIME_VSYSCALL
28b1a824 134 select GENERIC_GETTIMEOFDAY
9614cc57 135 select GENERIC_VDSO_TIME_NS
a1ddc74a 136 select HANDLE_DOMAIN_IRQ
8c2c3df3 137 select HARDIRQS_SW_RESEND
45544eee 138 select HAVE_MOVE_PMD
f5308c89 139 select HAVE_MOVE_PUD
eb01d42a 140 select HAVE_PCI
9f9a35a7 141 select HAVE_ACPI_APEI if (ACPI && EFI)
5284e1b4 142 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
875cbf3e 143 select HAVE_ARCH_AUDITSYSCALL
8e7a4cef 144 select HAVE_ARCH_BITREVERSE
689eae42 145 select HAVE_ARCH_COMPILER_H
324420bf 146 select HAVE_ARCH_HUGE_VMAP
9732cafd 147 select HAVE_ARCH_JUMP_LABEL
c296146c 148 select HAVE_ARCH_JUMP_LABEL_RELATIVE
e17d8025 149 select HAVE_ARCH_KASAN if !(ARM64_16K_PAGES && ARM64_VA_BITS_48)
71b613fc 150 select HAVE_ARCH_KASAN_VMALLOC if HAVE_ARCH_KASAN
2d4acb90 151 select HAVE_ARCH_KASAN_SW_TAGS if HAVE_ARCH_KASAN
94ab5b61 152 select HAVE_ARCH_KASAN_HW_TAGS if (HAVE_ARCH_KASAN && ARM64_MTE)
840b2398 153 select HAVE_ARCH_KFENCE
9529247d 154 select HAVE_ARCH_KGDB
8f0d3aa9
DC
155 select HAVE_ARCH_MMAP_RND_BITS
156 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT
3eb9cdff 157 select HAVE_ARCH_PFN_VALID
271ca788 158 select HAVE_ARCH_PREL32_RELOCATIONS
70918779 159 select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET
a1ae65b2 160 select HAVE_ARCH_SECCOMP_FILTER
0b3e3366 161 select HAVE_ARCH_STACKLEAK
9e8084d3 162 select HAVE_ARCH_THREAD_STRUCT_WHITELIST
8c2c3df3 163 select HAVE_ARCH_TRACEHOOK
8ee70879 164 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
e3067861 165 select HAVE_ARCH_VMAP_STACK
8ee70879 166 select HAVE_ARM_SMCCC
2ff2b7ec 167 select HAVE_ASM_MODVERSIONS
6077776b 168 select HAVE_EBPF_JIT
af64d2aa 169 select HAVE_C_RECORDMCOUNT
5284e1b4 170 select HAVE_CMPXCHG_DOUBLE
95eff6b2 171 select HAVE_CMPXCHG_LOCAL
8ee70879 172 select HAVE_CONTEXT_TRACKING
b69ec42b 173 select HAVE_DEBUG_KMEMLEAK
6ac2104d 174 select HAVE_DMA_CONTIGUOUS
bd7d38db 175 select HAVE_DYNAMIC_FTRACE
3b23e499
TD
176 select HAVE_DYNAMIC_FTRACE_WITH_REGS \
177 if $(cc-option,-fpatchable-function-entry=2)
a31d793d
ST
178 select FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY \
179 if DYNAMIC_FTRACE_WITH_REGS
50afc33a 180 select HAVE_EFFICIENT_UNALIGNED_ACCESS
67a929e0 181 select HAVE_FAST_GUP
af64d2aa 182 select HAVE_FTRACE_MCOUNT_RECORD
819e50e2 183 select HAVE_FUNCTION_TRACER
42d038c4 184 select HAVE_FUNCTION_ERROR_INJECTION
819e50e2 185 select HAVE_FUNCTION_GRAPH_TRACER
6b90bd4b 186 select HAVE_GCC_PLUGINS
8c2c3df3 187 select HAVE_HW_BREAKPOINT if PERF_EVENTS
24da208d 188 select HAVE_IRQ_TIME_ACCOUNTING
396a5d4a 189 select HAVE_NMI
55834a77 190 select HAVE_PATA_PLATFORM
8c2c3df3 191 select HAVE_PERF_EVENTS
2ee0d7fd
JP
192 select HAVE_PERF_REGS
193 select HAVE_PERF_USER_STACK_DUMP
0a8ea52c 194 select HAVE_REGS_AND_STACK_ACCESS_API
a823c35f 195 select HAVE_FUNCTION_ARG_ACCESS_API
98346023 196 select HAVE_FUTEX_CMPXCHG if FUTEX
ff2e6d72 197 select MMU_GATHER_RCU_TABLE_FREE
409d5db4 198 select HAVE_RSEQ
d148eac0 199 select HAVE_STACKPROTECTOR
055b1212 200 select HAVE_SYSCALL_TRACEPOINTS
2dd0e8d2 201 select HAVE_KPROBES
cd1ee3b1 202 select HAVE_KRETPROBES
28b1a824 203 select HAVE_GENERIC_VDSO
876945db 204 select IOMMU_DMA if IOMMU_SUPPORT
8c2c3df3 205 select IRQ_DOMAIN
e8557d1f 206 select IRQ_FORCED_THREADING
acc3042d 207 select KASAN_VMALLOC if KASAN_GENERIC
fea2acaa 208 select MODULES_USE_ELF_RELA
f616ab59 209 select NEED_DMA_MAP_STATE
86596f0a 210 select NEED_SG_DMA_LENGTH
8c2c3df3
CM
211 select OF
212 select OF_EARLY_FLATTREE
2eac9c2d 213 select PCI_DOMAINS_GENERIC if PCI
52146173 214 select PCI_ECAM if (ACPI && PCI)
20f1b79d 215 select PCI_SYSCALL if PCI
aa1e8ec1
CM
216 select POWER_RESET
217 select POWER_SUPPLY
8c2c3df3 218 select SPARSE_IRQ
09230cbc 219 select SWIOTLB
7ac57a89 220 select SYSCTL_EXCEPTION_TRACE
c02433dd 221 select THREAD_INFO_IN_TASK
7677f7fd 222 select HAVE_ARCH_USERFAULTFD_MINOR if USERFAULTFD
4aae683f 223 select TRACE_IRQFLAGS_SUPPORT
8c2c3df3
CM
224 help
225 ARM 64-bit (AArch64) Linux support.
226
227config 64BIT
228 def_bool y
229
8c2c3df3
CM
230config MMU
231 def_bool y
232
030c4d24
MR
233config ARM64_PAGE_SHIFT
234 int
235 default 16 if ARM64_64K_PAGES
236 default 14 if ARM64_16K_PAGES
237 default 12
238
c0d6de32 239config ARM64_CONT_PTE_SHIFT
030c4d24
MR
240 int
241 default 5 if ARM64_64K_PAGES
242 default 7 if ARM64_16K_PAGES
243 default 4
244
e6765941
GS
245config ARM64_CONT_PMD_SHIFT
246 int
247 default 5 if ARM64_64K_PAGES
248 default 5 if ARM64_16K_PAGES
249 default 4
250
8f0d3aa9
DC
251config ARCH_MMAP_RND_BITS_MIN
252 default 14 if ARM64_64K_PAGES
253 default 16 if ARM64_16K_PAGES
254 default 18
255
256# max bits determined by the following formula:
257# VA_BITS - PAGE_SHIFT - 3
258config ARCH_MMAP_RND_BITS_MAX
259 default 19 if ARM64_VA_BITS=36
260 default 24 if ARM64_VA_BITS=39
261 default 27 if ARM64_VA_BITS=42
262 default 30 if ARM64_VA_BITS=47
263 default 29 if ARM64_VA_BITS=48 && ARM64_64K_PAGES
264 default 31 if ARM64_VA_BITS=48 && ARM64_16K_PAGES
265 default 33 if ARM64_VA_BITS=48
266 default 14 if ARM64_64K_PAGES
267 default 16 if ARM64_16K_PAGES
268 default 18
269
270config ARCH_MMAP_RND_COMPAT_BITS_MIN
271 default 7 if ARM64_64K_PAGES
272 default 9 if ARM64_16K_PAGES
273 default 11
274
275config ARCH_MMAP_RND_COMPAT_BITS_MAX
276 default 16
277
ce816fa8 278config NO_IOPORT_MAP
d1e6dc91 279 def_bool y if !PCI
8c2c3df3
CM
280
281config STACKTRACE_SUPPORT
282 def_bool y
283
bf0c4e04
JVS
284config ILLEGAL_POINTER_VALUE
285 hex
286 default 0xdead000000000000
287
8c2c3df3
CM
288config LOCKDEP_SUPPORT
289 def_bool y
290
9fb7410f
DM
291config GENERIC_BUG
292 def_bool y
293 depends on BUG
294
295config GENERIC_BUG_RELATIVE_POINTERS
296 def_bool y
297 depends on GENERIC_BUG
298
8c2c3df3
CM
299config GENERIC_HWEIGHT
300 def_bool y
301
302config GENERIC_CSUM
303 def_bool y
304
305config GENERIC_CALIBRATE_DELAY
306 def_bool y
307
ca6e51d5
OS
308config ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE
309 def_bool y
310
4b3dc967
WD
311config SMP
312 def_bool y
313
4cfb3613
AB
314config KERNEL_MODE_NEON
315 def_bool y
316
92cc15fc
RH
317config FIX_EARLYCON_MEM
318 def_bool y
319
9f25e6ad
KS
320config PGTABLE_LEVELS
321 int
21539939 322 default 2 if ARM64_16K_PAGES && ARM64_VA_BITS_36
9f25e6ad 323 default 2 if ARM64_64K_PAGES && ARM64_VA_BITS_42
b6d00d47 324 default 3 if ARM64_64K_PAGES && (ARM64_VA_BITS_48 || ARM64_VA_BITS_52)
9f25e6ad 325 default 3 if ARM64_4K_PAGES && ARM64_VA_BITS_39
44eaacf1
SP
326 default 3 if ARM64_16K_PAGES && ARM64_VA_BITS_47
327 default 4 if !ARM64_64K_PAGES && ARM64_VA_BITS_48
9f25e6ad 328
9842ceae
PA
329config ARCH_SUPPORTS_UPROBES
330 def_bool y
331
8f360948
AB
332config ARCH_PROC_KCORE_TEXT
333 def_bool y
334
8bf9284d
VM
335config BROKEN_GAS_INST
336 def_bool !$(as-instr,1:\n.inst 0\n.rept . - 1b\n\nnop\n.endr\n)
337
6bd1d0be
SC
338config KASAN_SHADOW_OFFSET
339 hex
0fea6e9a 340 depends on KASAN_GENERIC || KASAN_SW_TAGS
f4693c27
AB
341 default 0xdfff800000000000 if (ARM64_VA_BITS_48 || ARM64_VA_BITS_52) && !KASAN_SW_TAGS
342 default 0xdfffc00000000000 if ARM64_VA_BITS_47 && !KASAN_SW_TAGS
343 default 0xdffffe0000000000 if ARM64_VA_BITS_42 && !KASAN_SW_TAGS
344 default 0xdfffffc000000000 if ARM64_VA_BITS_39 && !KASAN_SW_TAGS
345 default 0xdffffff800000000 if ARM64_VA_BITS_36 && !KASAN_SW_TAGS
346 default 0xefff800000000000 if (ARM64_VA_BITS_48 || ARM64_VA_BITS_52) && KASAN_SW_TAGS
347 default 0xefffc00000000000 if ARM64_VA_BITS_47 && KASAN_SW_TAGS
348 default 0xeffffe0000000000 if ARM64_VA_BITS_42 && KASAN_SW_TAGS
349 default 0xefffffc000000000 if ARM64_VA_BITS_39 && KASAN_SW_TAGS
350 default 0xeffffff800000000 if ARM64_VA_BITS_36 && KASAN_SW_TAGS
6bd1d0be
SC
351 default 0xffffffffffffffff
352
6a377491 353source "arch/arm64/Kconfig.platforms"
8c2c3df3 354
8c2c3df3
CM
355menu "Kernel Features"
356
c0a01b84
AP
357menu "ARM errata workarounds via the alternatives framework"
358
c9460dcb 359config ARM64_WORKAROUND_CLEAN_CACHE
bc15cf70 360 bool
c9460dcb 361
c0a01b84
AP
362config ARM64_ERRATUM_826319
363 bool "Cortex-A53: 826319: System might deadlock if a write cannot complete until read data is accepted"
364 default y
c9460dcb 365 select ARM64_WORKAROUND_CLEAN_CACHE
c0a01b84
AP
366 help
367 This option adds an alternative code sequence to work around ARM
368 erratum 826319 on Cortex-A53 parts up to r0p2 with an AMBA 4 ACE or
369 AXI master interface and an L2 cache.
370
371 If a Cortex-A53 uses an AMBA AXI4 ACE interface to other processors
372 and is unable to accept a certain write via this interface, it will
373 not progress on read data presented on the read data channel and the
374 system can deadlock.
375
376 The workaround promotes data cache clean instructions to
377 data cache clean-and-invalidate.
378 Please note that this does not necessarily enable the workaround,
379 as it depends on the alternative framework, which will only patch
380 the kernel if an affected CPU is detected.
381
382 If unsure, say Y.
383
384config ARM64_ERRATUM_827319
385 bool "Cortex-A53: 827319: Data cache clean instructions might cause overlapping transactions to the interconnect"
386 default y
c9460dcb 387 select ARM64_WORKAROUND_CLEAN_CACHE
c0a01b84
AP
388 help
389 This option adds an alternative code sequence to work around ARM
390 erratum 827319 on Cortex-A53 parts up to r0p2 with an AMBA 5 CHI
391 master interface and an L2 cache.
392
393 Under certain conditions this erratum can cause a clean line eviction
394 to occur at the same time as another transaction to the same address
395 on the AMBA 5 CHI interface, which can cause data corruption if the
396 interconnect reorders the two transactions.
397
398 The workaround promotes data cache clean instructions to
399 data cache clean-and-invalidate.
400 Please note that this does not necessarily enable the workaround,
401 as it depends on the alternative framework, which will only patch
402 the kernel if an affected CPU is detected.
403
404 If unsure, say Y.
405
406config ARM64_ERRATUM_824069
407 bool "Cortex-A53: 824069: Cache line might not be marked as clean after a CleanShared snoop"
408 default y
c9460dcb 409 select ARM64_WORKAROUND_CLEAN_CACHE
c0a01b84
AP
410 help
411 This option adds an alternative code sequence to work around ARM
412 erratum 824069 on Cortex-A53 parts up to r0p2 when it is connected
413 to a coherent interconnect.
414
415 If a Cortex-A53 processor is executing a store or prefetch for
416 write instruction at the same time as a processor in another
417 cluster is executing a cache maintenance operation to the same
418 address, then this erratum might cause a clean cache line to be
419 incorrectly marked as dirty.
420
421 The workaround promotes data cache clean instructions to
422 data cache clean-and-invalidate.
423 Please note that this option does not necessarily enable the
424 workaround, as it depends on the alternative framework, which will
425 only patch the kernel if an affected CPU is detected.
426
427 If unsure, say Y.
428
429config ARM64_ERRATUM_819472
430 bool "Cortex-A53: 819472: Store exclusive instructions might cause data corruption"
431 default y
c9460dcb 432 select ARM64_WORKAROUND_CLEAN_CACHE
c0a01b84
AP
433 help
434 This option adds an alternative code sequence to work around ARM
435 erratum 819472 on Cortex-A53 parts up to r0p1 with an L2 cache
436 present when it is connected to a coherent interconnect.
437
438 If the processor is executing a load and store exclusive sequence at
439 the same time as a processor in another cluster is executing a cache
440 maintenance operation to the same address, then this erratum might
441 cause data corruption.
442
443 The workaround promotes data cache clean instructions to
444 data cache clean-and-invalidate.
445 Please note that this does not necessarily enable the workaround,
446 as it depends on the alternative framework, which will only patch
447 the kernel if an affected CPU is detected.
448
449 If unsure, say Y.
450
451config ARM64_ERRATUM_832075
452 bool "Cortex-A57: 832075: possible deadlock on mixing exclusive memory accesses with device loads"
453 default y
454 help
455 This option adds an alternative code sequence to work around ARM
456 erratum 832075 on Cortex-A57 parts up to r1p2.
457
458 Affected Cortex-A57 parts might deadlock when exclusive load/store
459 instructions to Write-Back memory are mixed with Device loads.
460
461 The workaround is to promote device loads to use Load-Acquire
462 semantics.
463 Please note that this does not necessarily enable the workaround,
498cd5c3
MZ
464 as it depends on the alternative framework, which will only patch
465 the kernel if an affected CPU is detected.
466
467 If unsure, say Y.
468
469config ARM64_ERRATUM_834220
470 bool "Cortex-A57: 834220: Stage 2 translation fault might be incorrectly reported in presence of a Stage 1 fault"
471 depends on KVM
472 default y
473 help
474 This option adds an alternative code sequence to work around ARM
475 erratum 834220 on Cortex-A57 parts up to r1p2.
476
477 Affected Cortex-A57 parts might report a Stage 2 translation
478 fault as the result of a Stage 1 fault for load crossing a
479 page boundary when there is a permission or device memory
480 alignment fault at Stage 1 and a translation fault at Stage 2.
481
482 The workaround is to verify that the Stage 1 translation
483 doesn't generate a fault before handling the Stage 2 fault.
484 Please note that this does not necessarily enable the workaround,
c0a01b84
AP
485 as it depends on the alternative framework, which will only patch
486 the kernel if an affected CPU is detected.
487
488 If unsure, say Y.
489
905e8c5d
WD
490config ARM64_ERRATUM_845719
491 bool "Cortex-A53: 845719: a load might read incorrect data"
492 depends on COMPAT
493 default y
494 help
495 This option adds an alternative code sequence to work around ARM
496 erratum 845719 on Cortex-A53 parts up to r0p4.
497
498 When running a compat (AArch32) userspace on an affected Cortex-A53
499 part, a load at EL0 from a virtual address that matches the bottom 32
500 bits of the virtual address used by a recent load at (AArch64) EL1
501 might return incorrect data.
502
503 The workaround is to write the contextidr_el1 register on exception
504 return to a 32-bit task.
505 Please note that this does not necessarily enable the workaround,
506 as it depends on the alternative framework, which will only patch
507 the kernel if an affected CPU is detected.
508
509 If unsure, say Y.
510
df057cc7
WD
511config ARM64_ERRATUM_843419
512 bool "Cortex-A53: 843419: A load or store might access an incorrect address"
df057cc7 513 default y
a257e025 514 select ARM64_MODULE_PLTS if MODULES
df057cc7 515 help
6ffe9923 516 This option links the kernel with '--fix-cortex-a53-843419' and
a257e025
AB
517 enables PLT support to replace certain ADRP instructions, which can
518 cause subsequent memory accesses to use an incorrect address on
519 Cortex-A53 parts up to r0p4.
df057cc7
WD
520
521 If unsure, say Y.
522
987fdfec
MY
523config ARM64_LD_HAS_FIX_ERRATUM_843419
524 def_bool $(ld-option,--fix-cortex-a53-843419)
525
ece1397c
SP
526config ARM64_ERRATUM_1024718
527 bool "Cortex-A55: 1024718: Update of DBM/AP bits without break before make might result in incorrect update"
528 default y
529 help
bc15cf70 530 This option adds a workaround for ARM Cortex-A55 Erratum 1024718.
ece1397c 531
c0b15c25 532 Affected Cortex-A55 cores (all revisions) could cause incorrect
ece1397c 533 update of the hardware dirty bit when the DBM/AP bits are updated
bc15cf70 534 without a break-before-make. The workaround is to disable the usage
ece1397c 535 of hardware DBM locally on the affected cores. CPUs not affected by
bc15cf70 536 this erratum will continue to use the feature.
df057cc7
WD
537
538 If unsure, say Y.
539
a5325089 540config ARM64_ERRATUM_1418040
6989303a 541 bool "Cortex-A76/Neoverse-N1: MRC read following MRRC read of specific Generic Timer in AArch32 might give incorrect result"
95b861a4 542 default y
c2b5bba3 543 depends on COMPAT
95b861a4 544 help
24cf262d 545 This option adds a workaround for ARM Cortex-A76/Neoverse-N1
a5325089 546 errata 1188873 and 1418040.
95b861a4 547
a5325089 548 Affected Cortex-A76/Neoverse-N1 cores (r0p0 to r3p1) could
6989303a
MZ
549 cause register corruption when accessing the timer registers
550 from AArch32 userspace.
95b861a4
MZ
551
552 If unsure, say Y.
553
02ab1f50 554config ARM64_WORKAROUND_SPECULATIVE_AT
e85d68fa
SP
555 bool
556
a457b0f7 557config ARM64_ERRATUM_1165522
02ab1f50 558 bool "Cortex-A76: 1165522: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
a457b0f7 559 default y
02ab1f50 560 select ARM64_WORKAROUND_SPECULATIVE_AT
a457b0f7 561 help
bc15cf70 562 This option adds a workaround for ARM Cortex-A76 erratum 1165522.
a457b0f7
MZ
563
564 Affected Cortex-A76 cores (r0p0, r1p0, r2p0) could end-up with
565 corrupted TLBs by speculating an AT instruction during a guest
566 context switch.
567
568 If unsure, say Y.
569
02ab1f50
AS
570config ARM64_ERRATUM_1319367
571 bool "Cortex-A57/A72: 1319537: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
572 default y
573 select ARM64_WORKAROUND_SPECULATIVE_AT
574 help
575 This option adds work arounds for ARM Cortex-A57 erratum 1319537
576 and A72 erratum 1319367
577
578 Cortex-A57 and A72 cores could end-up with corrupted TLBs by
579 speculating an AT instruction during a guest context switch.
580
581 If unsure, say Y.
582
275fa0ea 583config ARM64_ERRATUM_1530923
02ab1f50 584 bool "Cortex-A55: 1530923: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
275fa0ea 585 default y
02ab1f50 586 select ARM64_WORKAROUND_SPECULATIVE_AT
275fa0ea
SP
587 help
588 This option adds a workaround for ARM Cortex-A55 erratum 1530923.
589
590 Affected Cortex-A55 cores (r0p0, r0p1, r1p0, r2p0) could end-up with
591 corrupted TLBs by speculating an AT instruction during a guest
592 context switch.
593
594 If unsure, say Y.
a457b0f7 595
ebcea694
GU
596config ARM64_WORKAROUND_REPEAT_TLBI
597 bool
598
ce8c80c5
CM
599config ARM64_ERRATUM_1286807
600 bool "Cortex-A76: Modification of the translation table for a virtual address might lead to read-after-read ordering violation"
601 default y
602 select ARM64_WORKAROUND_REPEAT_TLBI
603 help
bc15cf70 604 This option adds a workaround for ARM Cortex-A76 erratum 1286807.
ce8c80c5
CM
605
606 On the affected Cortex-A76 cores (r0p0 to r3p0), if a virtual
607 address for a cacheable mapping of a location is being
608 accessed by a core while another core is remapping the virtual
609 address to a new physical page using the recommended
610 break-before-make sequence, then under very rare circumstances
611 TLBI+DSB completes before a read using the translation being
612 invalidated has been observed by other observers. The
613 workaround repeats the TLBI+DSB operation.
614
969f5ea6
WD
615config ARM64_ERRATUM_1463225
616 bool "Cortex-A76: Software Step might prevent interrupt recognition"
617 default y
618 help
619 This option adds a workaround for Arm Cortex-A76 erratum 1463225.
620
621 On the affected Cortex-A76 cores (r0p0 to r3p1), software stepping
622 of a system call instruction (SVC) can prevent recognition of
623 subsequent interrupts when software stepping is disabled in the
624 exception handler of the system call and either kernel debugging
625 is enabled or VHE is in use.
626
627 Work around the erratum by triggering a dummy step exception
628 when handling a system call from a task that is being stepped
629 in a VHE configuration of the kernel.
630
631 If unsure, say Y.
632
05460849
JM
633config ARM64_ERRATUM_1542419
634 bool "Neoverse-N1: workaround mis-ordering of instruction fetches"
635 default y
636 help
637 This option adds a workaround for ARM Neoverse-N1 erratum
638 1542419.
639
640 Affected Neoverse-N1 cores could execute a stale instruction when
641 modified by another CPU. The workaround depends on a firmware
642 counterpart.
643
644 Workaround the issue by hiding the DIC feature from EL0. This
645 forces user-space to perform cache maintenance.
646
647 If unsure, say Y.
648
96d389ca
RH
649config ARM64_ERRATUM_1508412
650 bool "Cortex-A77: 1508412: workaround deadlock on sequence of NC/Device load and store exclusive or PAR read"
651 default y
652 help
653 This option adds a workaround for Arm Cortex-A77 erratum 1508412.
654
655 Affected Cortex-A77 cores (r0p0, r1p0) could deadlock on a sequence
656 of a store-exclusive or read of PAR_EL1 and a load with device or
657 non-cacheable memory attributes. The workaround depends on a firmware
658 counterpart.
659
660 KVM guests must also have the workaround implemented or they can
661 deadlock the system.
662
663 Work around the issue by inserting DMB SY barriers around PAR_EL1
664 register reads and warning KVM users. The DMB barrier is sufficient
665 to prevent a speculative PAR_EL1 read.
666
667 If unsure, say Y.
668
94100970
RR
669config CAVIUM_ERRATUM_22375
670 bool "Cavium erratum 22375, 24313"
671 default y
672 help
bc15cf70 673 Enable workaround for errata 22375 and 24313.
94100970
RR
674
675 This implements two gicv3-its errata workarounds for ThunderX. Both
bc15cf70 676 with a small impact affecting only ITS table allocation.
94100970
RR
677
678 erratum 22375: only alloc 8MB table size
679 erratum 24313: ignore memory access type
680
681 The fixes are in ITS initialization and basically ignore memory access
682 type and table size provided by the TYPER and BASER registers.
683
684 If unsure, say Y.
685
fbf8f40e
GK
686config CAVIUM_ERRATUM_23144
687 bool "Cavium erratum 23144: ITS SYNC hang on dual socket system"
688 depends on NUMA
689 default y
690 help
691 ITS SYNC command hang for cross node io and collections/cpu mapping.
692
693 If unsure, say Y.
694
6d4e11c5
RR
695config CAVIUM_ERRATUM_23154
696 bool "Cavium erratum 23154: Access to ICC_IAR1_EL1 is not sync'ed"
697 default y
698 help
699 The gicv3 of ThunderX requires a modified version for
700 reading the IAR status to ensure data synchronization
701 (access to icc_iar1_el1 is not sync'ed before and after).
702
703 If unsure, say Y.
704
104a0c02
AP
705config CAVIUM_ERRATUM_27456
706 bool "Cavium erratum 27456: Broadcast TLBI instructions may cause icache corruption"
707 default y
708 help
709 On ThunderX T88 pass 1.x through 2.1 parts, broadcast TLBI
710 instructions may cause the icache to become corrupted if it
711 contains data for a non-current ASID. The fix is to
712 invalidate the icache when changing the mm context.
713
714 If unsure, say Y.
715
690a3415
DD
716config CAVIUM_ERRATUM_30115
717 bool "Cavium erratum 30115: Guest may disable interrupts in host"
718 default y
719 help
720 On ThunderX T88 pass 1.x through 2.2, T81 pass 1.0 through
721 1.2, and T83 Pass 1.0, KVM guest execution may disable
722 interrupts in host. Trapping both GICv3 group-0 and group-1
723 accesses sidesteps the issue.
724
725 If unsure, say Y.
726
603afdc9
MZ
727config CAVIUM_TX2_ERRATUM_219
728 bool "Cavium ThunderX2 erratum 219: PRFM between TTBR change and ISB fails"
729 default y
730 help
731 On Cavium ThunderX2, a load, store or prefetch instruction between a
732 TTBR update and the corresponding context synchronizing operation can
733 cause a spurious Data Abort to be delivered to any hardware thread in
734 the CPU core.
735
736 Work around the issue by avoiding the problematic code sequence and
737 trapping KVM guest TTBRx_EL1 writes to EL2 when SMT is enabled. The
738 trap handler performs the corresponding register access, skips the
739 instruction and ensures context synchronization by virtue of the
740 exception return.
741
742 If unsure, say Y.
743
ebcea694
GU
744config FUJITSU_ERRATUM_010001
745 bool "Fujitsu-A64FX erratum E#010001: Undefined fault may occur wrongly"
746 default y
747 help
748 This option adds a workaround for Fujitsu-A64FX erratum E#010001.
749 On some variants of the Fujitsu-A64FX cores ver(1.0, 1.1), memory
750 accesses may cause undefined fault (Data abort, DFSC=0b111111).
751 This fault occurs under a specific hardware condition when a
752 load/store instruction performs an address translation using:
753 case-1 TTBR0_EL1 with TCR_EL1.NFD0 == 1.
754 case-2 TTBR0_EL2 with TCR_EL2.NFD0 == 1.
755 case-3 TTBR1_EL1 with TCR_EL1.NFD1 == 1.
756 case-4 TTBR1_EL2 with TCR_EL2.NFD1 == 1.
757
758 The workaround is to ensure these bits are clear in TCR_ELx.
759 The workaround only affects the Fujitsu-A64FX.
760
761 If unsure, say Y.
762
763config HISILICON_ERRATUM_161600802
764 bool "Hip07 161600802: Erroneous redistributor VLPI base"
765 default y
766 help
767 The HiSilicon Hip07 SoC uses the wrong redistributor base
768 when issued ITS commands such as VMOVP and VMAPP, and requires
769 a 128kB offset to be applied to the target address in this commands.
770
771 If unsure, say Y.
772
38fd94b0
CC
773config QCOM_FALKOR_ERRATUM_1003
774 bool "Falkor E1003: Incorrect translation due to ASID change"
775 default y
38fd94b0
CC
776 help
777 On Falkor v1, an incorrect ASID may be cached in the TLB when ASID
d1777e68
WD
778 and BADDR are changed together in TTBRx_EL1. Since we keep the ASID
779 in TTBR1_EL1, this situation only occurs in the entry trampoline and
780 then only for entries in the walk cache, since the leaf translation
781 is unchanged. Work around the erratum by invalidating the walk cache
782 entries for the trampoline before entering the kernel proper.
38fd94b0 783
d9ff80f8
CC
784config QCOM_FALKOR_ERRATUM_1009
785 bool "Falkor E1009: Prematurely complete a DSB after a TLBI"
786 default y
ce8c80c5 787 select ARM64_WORKAROUND_REPEAT_TLBI
d9ff80f8
CC
788 help
789 On Falkor v1, the CPU may prematurely complete a DSB following a
790 TLBI xxIS invalidate maintenance operation. Repeat the TLBI operation
791 one more time to fix the issue.
792
793 If unsure, say Y.
794
90922a2d
SD
795config QCOM_QDF2400_ERRATUM_0065
796 bool "QDF2400 E0065: Incorrect GITS_TYPER.ITT_Entry_size"
797 default y
798 help
799 On Qualcomm Datacenter Technologies QDF2400 SoC, ITS hardware reports
800 ITE size incorrectly. The GITS_TYPER.ITT_Entry_size field should have
801 been indicated as 16Bytes (0xf), not 8Bytes (0x7).
802
803 If unsure, say Y.
804
932b50c7
SD
805config QCOM_FALKOR_ERRATUM_E1041
806 bool "Falkor E1041: Speculative instruction fetches might cause errant memory access"
807 default y
808 help
809 Falkor CPU may speculatively fetch instructions from an improper
810 memory location when MMU translation is changed from SCTLR_ELn[M]=1
811 to SCTLR_ELn[M]=0. Prefix an ISB instruction to fix the problem.
812
813 If unsure, say Y.
814
20109a85
RW
815config NVIDIA_CARMEL_CNP_ERRATUM
816 bool "NVIDIA Carmel CNP: CNP on Carmel semantically different than ARM cores"
817 default y
818 help
819 If CNP is enabled on Carmel cores, non-sharable TLBIs on a core will not
820 invalidate shared TLB entries installed by a different core, as it would
821 on standard ARM cores.
822
823 If unsure, say Y.
824
ebcea694
GU
825config SOCIONEXT_SYNQUACER_PREITS
826 bool "Socionext Synquacer: Workaround for GICv3 pre-ITS"
3e32131a
ZL
827 default y
828 help
ebcea694
GU
829 Socionext Synquacer SoCs implement a separate h/w block to generate
830 MSI doorbell writes with non-zero values for the device ID.
3e32131a
ZL
831
832 If unsure, say Y.
833
c0a01b84
AP
834endmenu
835
836
e41ceed0
JL
837choice
838 prompt "Page size"
839 default ARM64_4K_PAGES
840 help
841 Page size (translation granule) configuration.
842
843config ARM64_4K_PAGES
844 bool "4KB"
845 help
846 This feature enables 4KB pages support.
847
44eaacf1
SP
848config ARM64_16K_PAGES
849 bool "16KB"
850 help
851 The system will use 16KB pages support. AArch32 emulation
852 requires applications compiled with 16K (or a multiple of 16K)
853 aligned segments.
854
8c2c3df3 855config ARM64_64K_PAGES
e41ceed0 856 bool "64KB"
8c2c3df3
CM
857 help
858 This feature enables 64KB pages support (4KB by default)
859 allowing only two levels of page tables and faster TLB
db488be3
SP
860 look-up. AArch32 emulation requires applications compiled
861 with 64K aligned segments.
8c2c3df3 862
e41ceed0
JL
863endchoice
864
865choice
866 prompt "Virtual address space size"
867 default ARM64_VA_BITS_39 if ARM64_4K_PAGES
44eaacf1 868 default ARM64_VA_BITS_47 if ARM64_16K_PAGES
e41ceed0
JL
869 default ARM64_VA_BITS_42 if ARM64_64K_PAGES
870 help
871 Allows choosing one of multiple possible virtual address
872 space sizes. The level of translation table is determined by
873 a combination of page size and virtual address space size.
874
21539939 875config ARM64_VA_BITS_36
56a3f30e 876 bool "36-bit" if EXPERT
21539939
SP
877 depends on ARM64_16K_PAGES
878
e41ceed0
JL
879config ARM64_VA_BITS_39
880 bool "39-bit"
881 depends on ARM64_4K_PAGES
882
883config ARM64_VA_BITS_42
884 bool "42-bit"
885 depends on ARM64_64K_PAGES
886
44eaacf1
SP
887config ARM64_VA_BITS_47
888 bool "47-bit"
889 depends on ARM64_16K_PAGES
890
c79b954b
JL
891config ARM64_VA_BITS_48
892 bool "48-bit"
c79b954b 893
b6d00d47
SC
894config ARM64_VA_BITS_52
895 bool "52-bit"
68d23da4
WD
896 depends on ARM64_64K_PAGES && (ARM64_PAN || !ARM64_SW_TTBR0_PAN)
897 help
898 Enable 52-bit virtual addressing for userspace when explicitly
b6d00d47
SC
899 requested via a hint to mmap(). The kernel will also use 52-bit
900 virtual addresses for its own mappings (provided HW support for
901 this feature is available, otherwise it reverts to 48-bit).
68d23da4
WD
902
903 NOTE: Enabling 52-bit virtual addressing in conjunction with
904 ARMv8.3 Pointer Authentication will result in the PAC being
905 reduced from 7 bits to 3 bits, which may have a significant
906 impact on its susceptibility to brute-force attacks.
907
908 If unsure, select 48-bit virtual addressing instead.
909
e41ceed0
JL
910endchoice
911
68d23da4
WD
912config ARM64_FORCE_52BIT
913 bool "Force 52-bit virtual addresses for userspace"
b6d00d47 914 depends on ARM64_VA_BITS_52 && EXPERT
68d23da4
WD
915 help
916 For systems with 52-bit userspace VAs enabled, the kernel will attempt
917 to maintain compatibility with older software by providing 48-bit VAs
918 unless a hint is supplied to mmap.
919
920 This configuration option disables the 48-bit compatibility logic, and
921 forces all userspace addresses to be 52-bit on HW that supports it. One
922 should only enable this configuration option for stress testing userspace
923 memory management code. If unsure say N here.
924
e41ceed0
JL
925config ARM64_VA_BITS
926 int
21539939 927 default 36 if ARM64_VA_BITS_36
e41ceed0
JL
928 default 39 if ARM64_VA_BITS_39
929 default 42 if ARM64_VA_BITS_42
44eaacf1 930 default 47 if ARM64_VA_BITS_47
b6d00d47
SC
931 default 48 if ARM64_VA_BITS_48
932 default 52 if ARM64_VA_BITS_52
e41ceed0 933
982aa7c5
KM
934choice
935 prompt "Physical address space size"
936 default ARM64_PA_BITS_48
937 help
938 Choose the maximum physical address range that the kernel will
939 support.
940
941config ARM64_PA_BITS_48
942 bool "48-bit"
943
f77d2817
KM
944config ARM64_PA_BITS_52
945 bool "52-bit (ARMv8.2)"
946 depends on ARM64_64K_PAGES
947 depends on ARM64_PAN || !ARM64_SW_TTBR0_PAN
948 help
949 Enable support for a 52-bit physical address space, introduced as
950 part of the ARMv8.2-LPA extension.
951
952 With this enabled, the kernel will also continue to work on CPUs that
953 do not support ARMv8.2-LPA, but with some added memory overhead (and
954 minor performance overhead).
955
982aa7c5
KM
956endchoice
957
958config ARM64_PA_BITS
959 int
960 default 48 if ARM64_PA_BITS_48
f77d2817 961 default 52 if ARM64_PA_BITS_52
982aa7c5 962
d8e85e14
AR
963choice
964 prompt "Endianness"
965 default CPU_LITTLE_ENDIAN
966 help
967 Select the endianness of data accesses performed by the CPU. Userspace
968 applications will need to be compiled and linked for the endianness
969 that is selected here.
970
a872013d 971config CPU_BIG_ENDIAN
e9c6deee
NC
972 bool "Build big-endian kernel"
973 depends on !LD_IS_LLD || LLD_VERSION >= 130000
974 help
d8e85e14
AR
975 Say Y if you plan on running a kernel with a big-endian userspace.
976
977config CPU_LITTLE_ENDIAN
978 bool "Build little-endian kernel"
979 help
980 Say Y if you plan on running a kernel with a little-endian userspace.
981 This is usually the case for distributions targeting arm64.
982
983endchoice
a872013d 984
f6e763b9
MB
985config SCHED_MC
986 bool "Multi-core scheduler support"
f6e763b9
MB
987 help
988 Multi-core scheduler support improves the CPU scheduler's decision
989 making when dealing with multi-core CPU chips at a cost of slightly
990 increased overhead in some places. If unsure say N here.
991
992config SCHED_SMT
993 bool "SMT scheduler support"
f6e763b9
MB
994 help
995 Improves the CPU scheduler's decision making when dealing with
996 MultiThreading at a cost of slightly increased overhead in some
997 places. If unsure say N here.
998
8c2c3df3 999config NR_CPUS
62aa9655
GK
1000 int "Maximum number of CPUs (2-4096)"
1001 range 2 4096
846a415b 1002 default "256"
8c2c3df3 1003
9327e2c6
MR
1004config HOTPLUG_CPU
1005 bool "Support for hot-pluggable CPUs"
217d453d 1006 select GENERIC_IRQ_MIGRATION
9327e2c6
MR
1007 help
1008 Say Y here to experiment with turning CPUs off and on. CPUs
1009 can be controlled through /sys/devices/system/cpu.
1010
1a2db300
GK
1011# Common NUMA Features
1012config NUMA
4399e6cd 1013 bool "NUMA Memory Allocation and Scheduler Support"
ae3c107c 1014 select GENERIC_ARCH_NUMA
0c2a6cce
KW
1015 select ACPI_NUMA if ACPI
1016 select OF_NUMA
1a2db300 1017 help
4399e6cd 1018 Enable NUMA (Non-Uniform Memory Access) support.
1a2db300
GK
1019
1020 The kernel will try to allocate memory used by a CPU on the
1021 local memory of the CPU and add some more
1022 NUMA awareness to the kernel.
1023
1024config NODES_SHIFT
1025 int "Maximum NUMA Nodes (as a power of 2)"
1026 range 1 10
2a13c13b 1027 default "4"
a9ee6cf5 1028 depends on NUMA
1a2db300
GK
1029 help
1030 Specify the maximum number of NUMA Nodes available on the target
1031 system. Increases memory reserved to accommodate various tables.
1032
1033config USE_PERCPU_NUMA_NODE_ID
1034 def_bool y
1035 depends on NUMA
1036
7af3a0a9
ZL
1037config HAVE_SETUP_PER_CPU_AREA
1038 def_bool y
1039 depends on NUMA
1040
1041config NEED_PER_CPU_EMBED_FIRST_CHUNK
1042 def_bool y
1043 depends on NUMA
1044
8636a1f9 1045source "kernel/Kconfig.hz"
8c2c3df3 1046
8c2c3df3
CM
1047config ARCH_SPARSEMEM_ENABLE
1048 def_bool y
1049 select SPARSEMEM_VMEMMAP_ENABLE
782276b4 1050 select SPARSEMEM_VMEMMAP
e7d4bac4 1051
8c2c3df3 1052config HW_PERF_EVENTS
6475b2d8
MR
1053 def_bool y
1054 depends on ARM_PMU
8c2c3df3 1055
5287569a
ST
1056# Supported by clang >= 7.0
1057config CC_HAVE_SHADOW_CALL_STACK
1058 def_bool $(cc-option, -fsanitize=shadow-call-stack -ffixed-x18)
1059
dfd57bc3
SS
1060config PARAVIRT
1061 bool "Enable paravirtualization code"
1062 help
1063 This changes the kernel so it can modify itself when it is run
1064 under a hypervisor, potentially improving performance significantly
1065 over full virtualization.
1066
1067config PARAVIRT_TIME_ACCOUNTING
1068 bool "Paravirtual steal time accounting"
1069 select PARAVIRT
dfd57bc3
SS
1070 help
1071 Select this option to enable fine granularity task steal time
1072 accounting. Time spent executing other tasks in parallel with
1073 the current vCPU is discounted from the vCPU power. To account for
1074 that, there can be a small performance impact.
1075
1076 If in doubt, say N here.
1077
d28f6df1
GL
1078config KEXEC
1079 depends on PM_SLEEP_SMP
1080 select KEXEC_CORE
1081 bool "kexec system call"
a7f7f624 1082 help
d28f6df1
GL
1083 kexec is a system call that implements the ability to shutdown your
1084 current kernel, and to start another kernel. It is like a reboot
1085 but it is independent of the system firmware. And like a reboot
1086 you can start any kernel with it, not just Linux.
1087
3ddd9992
AT
1088config KEXEC_FILE
1089 bool "kexec file based system call"
1090 select KEXEC_CORE
dce92f6b 1091 select HAVE_IMA_KEXEC if IMA
3ddd9992
AT
1092 help
1093 This is new version of kexec system call. This system call is
1094 file based and takes file descriptors as system call argument
1095 for kernel and initramfs as opposed to list of segments as
1096 accepted by previous system call.
1097
99d5cadf 1098config KEXEC_SIG
732b7b93
AT
1099 bool "Verify kernel signature during kexec_file_load() syscall"
1100 depends on KEXEC_FILE
1101 help
1102 Select this option to verify a signature with loaded kernel
1103 image. If configured, any attempt of loading a image without
1104 valid signature will fail.
1105
1106 In addition to that option, you need to enable signature
1107 verification for the corresponding kernel image type being
1108 loaded in order for this to work.
1109
1110config KEXEC_IMAGE_VERIFY_SIG
1111 bool "Enable Image signature verification support"
1112 default y
99d5cadf 1113 depends on KEXEC_SIG
732b7b93
AT
1114 depends on EFI && SIGNED_PE_FILE_VERIFICATION
1115 help
1116 Enable Image signature verification support.
1117
1118comment "Support for PE file signature verification disabled"
99d5cadf 1119 depends on KEXEC_SIG
732b7b93
AT
1120 depends on !EFI || !SIGNED_PE_FILE_VERIFICATION
1121
e62aaeac
AT
1122config CRASH_DUMP
1123 bool "Build kdump crash kernel"
1124 help
1125 Generate crash dump after being started by kexec. This should
1126 be normally only set in special crash dump kernels which are
1127 loaded in the main kernel with kexec-tools into a specially
1128 reserved region and then later executed after a crash by
1129 kdump/kexec.
1130
330d4810 1131 For more details see Documentation/admin-guide/kdump/kdump.rst
e62aaeac 1132
072e3d96
PT
1133config TRANS_TABLE
1134 def_bool y
1135 depends on HIBERNATION
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
79cc2ed5 1151 default "14" if ARM64_64K_PAGES
c904ee69 1152 default "13" if (ARCH_THUNDER && ARM64_4K_PAGES)
79cc2ed5 1153 default "12" if ARM64_16K_PAGES
d03bb145 1154 default "11"
44eaacf1
SP
1155 help
1156 The kernel memory allocator divides physically contiguous memory
1157 blocks into "zones", where each zone is a power of two number of
1158 pages. This option selects the largest power of two that the kernel
1159 keeps in the memory allocator. If you need to allocate very large
1160 blocks of physically contiguous memory, then you may need to
1161 increase this value.
1162
1163 This config option is actually maximum order plus one. For example,
1164 a value of 11 means that the largest free memory block is 2^10 pages.
1165
1166 We make sure that we can allocate upto a HugePage size for each configuration.
1167 Hence we have :
1168 MAX_ORDER = (PMD_SHIFT - PAGE_SHIFT) + 1 => PAGE_SHIFT - 2
1169
1170 However for 4K, we choose a higher default value, 11 as opposed to 10, giving us
1171 4M allocations matching the default size used by generic code.
d03bb145 1172
084eb77c 1173config UNMAP_KERNEL_AT_EL0
0617052d 1174 bool "Unmap kernel when running in userspace (aka \"KAISER\")" if EXPERT
084eb77c
WD
1175 default y
1176 help
0617052d
WD
1177 Speculation attacks against some high-performance processors can
1178 be used to bypass MMU permission checks and leak kernel data to
1179 userspace. This can be defended against by unmapping the kernel
1180 when running in userspace, mapping it back in on exception entry
1181 via a trampoline page in the vector table.
084eb77c
WD
1182
1183 If unsure, say Y.
1184
61b7114e
JM
1185config MITIGATE_SPECTRE_BRANCH_HISTORY
1186 bool "Mitigate Spectre style attacks against branch history" if EXPERT
1187 default y
1188 help
1189 Speculation attacks against some high-performance processors can
1190 make use of branch history to influence future speculation.
1191 When taking an exception from user-space, a sequence of branches
1192 or a firmware call overwrites the branch history.
1193
c55191e9
AB
1194config RODATA_FULL_DEFAULT_ENABLED
1195 bool "Apply r/o permissions of VM areas also to their linear aliases"
1196 default y
1197 help
1198 Apply read-only attributes of VM areas to the linear alias of
1199 the backing pages as well. This prevents code or read-only data
1200 from being modified (inadvertently or intentionally) via another
1201 mapping of the same memory page. This additional enhancement can
1202 be turned off at runtime by passing rodata=[off|on] (and turned on
1203 with rodata=full if this option is set to 'n')
1204
1205 This requires the linear region to be mapped down to pages,
1206 which may adversely affect performance in some cases.
1207
dd523791
WD
1208config ARM64_SW_TTBR0_PAN
1209 bool "Emulate Privileged Access Never using TTBR0_EL1 switching"
1210 help
1211 Enabling this option prevents the kernel from accessing
1212 user-space memory directly by pointing TTBR0_EL1 to a reserved
1213 zeroed area and reserved ASID. The user access routines
1214 restore the valid TTBR0_EL1 temporarily.
1215
63f0c603
CM
1216config ARM64_TAGGED_ADDR_ABI
1217 bool "Enable the tagged user addresses syscall ABI"
1218 default y
1219 help
1220 When this option is enabled, user applications can opt in to a
1221 relaxed ABI via prctl() allowing tagged addresses to be passed
1222 to system calls as pointer arguments. For details, see
799c8510 1223 Documentation/arm64/tagged-address-abi.rst.
63f0c603 1224
dd523791
WD
1225menuconfig COMPAT
1226 bool "Kernel support for 32-bit EL0"
1227 depends on ARM64_4K_PAGES || EXPERT
dd523791
WD
1228 select HAVE_UID16
1229 select OLD_SIGSUSPEND3
1230 select COMPAT_OLD_SIGACTION
1231 help
1232 This option enables support for a 32-bit EL0 running under a 64-bit
1233 kernel at EL1. AArch32-specific components such as system calls,
1234 the user helper functions, VFP support and the ptrace interface are
1235 handled appropriately by the kernel.
1236
1237 If you use a page size other than 4KB (i.e, 16KB or 64KB), please be aware
1238 that you will only be able to execute AArch32 binaries that were compiled
1239 with page size aligned segments.
1240
1241 If you want to execute 32-bit userspace applications, say Y.
1242
1243if COMPAT
1244
1245config KUSER_HELPERS
7c4791c9 1246 bool "Enable kuser helpers page for 32-bit applications"
dd523791
WD
1247 default y
1248 help
1249 Warning: disabling this option may break 32-bit user programs.
1250
1251 Provide kuser helpers to compat tasks. The kernel provides
1252 helper code to userspace in read only form at a fixed location
1253 to allow userspace to be independent of the CPU type fitted to
1254 the system. This permits binaries to be run on ARMv4 through
1255 to ARMv8 without modification.
1256
dc7a12bd 1257 See Documentation/arm/kernel_user_helpers.rst for details.
dd523791
WD
1258
1259 However, the fixed address nature of these helpers can be used
1260 by ROP (return orientated programming) authors when creating
1261 exploits.
1262
1263 If all of the binaries and libraries which run on your platform
1264 are built specifically for your platform, and make no use of
1265 these helpers, then you can turn this option off to hinder
1266 such exploits. However, in that case, if a binary or library
1267 relying on those helpers is run, it will not function correctly.
1268
1269 Say N here only if you are absolutely certain that you do not
1270 need these helpers; otherwise, the safe option is to say Y.
1271
7c4791c9
WD
1272config COMPAT_VDSO
1273 bool "Enable vDSO for 32-bit applications"
169791c3
ND
1274 depends on !CPU_BIG_ENDIAN
1275 depends on (CC_IS_CLANG && LD_IS_LLD) || "$(CROSS_COMPILE_COMPAT)" != ""
7c4791c9
WD
1276 select GENERIC_COMPAT_VDSO
1277 default y
1278 help
1279 Place in the process address space of 32-bit applications an
1280 ELF shared object providing fast implementations of gettimeofday
1281 and clock_gettime.
1282
1283 You must have a 32-bit build of glibc 2.22 or later for programs
1284 to seamlessly take advantage of this.
dd523791 1285
625412c2
ND
1286config THUMB2_COMPAT_VDSO
1287 bool "Compile the 32-bit vDSO for Thumb-2 mode" if EXPERT
1288 depends on COMPAT_VDSO
1289 default y
1290 help
1291 Compile the compat vDSO with '-mthumb -fomit-frame-pointer' if y,
1292 otherwise with '-marm'.
1293
1b907f46
WD
1294menuconfig ARMV8_DEPRECATED
1295 bool "Emulate deprecated/obsolete ARMv8 instructions"
6cfa7cc4 1296 depends on SYSCTL
1b907f46
WD
1297 help
1298 Legacy software support may require certain instructions
1299 that have been deprecated or obsoleted in the architecture.
1300
1301 Enable this config to enable selective emulation of these
1302 features.
1303
1304 If unsure, say Y
1305
1306if ARMV8_DEPRECATED
1307
1308config SWP_EMULATION
1309 bool "Emulate SWP/SWPB instructions"
1310 help
1311 ARMv8 obsoletes the use of A32 SWP/SWPB instructions such that
1312 they are always undefined. Say Y here to enable software
1313 emulation of these instructions for userspace using LDXR/STXR.
dd720784
MB
1314 This feature can be controlled at runtime with the abi.swp
1315 sysctl which is disabled by default.
1b907f46
WD
1316
1317 In some older versions of glibc [<=2.8] SWP is used during futex
1318 trylock() operations with the assumption that the code will not
1319 be preempted. This invalid assumption may be more likely to fail
1320 with SWP emulation enabled, leading to deadlock of the user
1321 application.
1322
1323 NOTE: when accessing uncached shared regions, LDXR/STXR rely
1324 on an external transaction monitoring block called a global
1325 monitor to maintain update atomicity. If your system does not
1326 implement a global monitor, this option can cause programs that
1327 perform SWP operations to uncached memory to deadlock.
1328
1329 If unsure, say Y
1330
1331config CP15_BARRIER_EMULATION
1332 bool "Emulate CP15 Barrier instructions"
1333 help
1334 The CP15 barrier instructions - CP15ISB, CP15DSB, and
1335 CP15DMB - are deprecated in ARMv8 (and ARMv7). It is
1336 strongly recommended to use the ISB, DSB, and DMB
1337 instructions instead.
1338
1339 Say Y here to enable software emulation of these
1340 instructions for AArch32 userspace code. When this option is
1341 enabled, CP15 barrier usage is traced which can help
dd720784
MB
1342 identify software that needs updating. This feature can be
1343 controlled at runtime with the abi.cp15_barrier sysctl.
1b907f46
WD
1344
1345 If unsure, say Y
1346
2d888f48
SP
1347config SETEND_EMULATION
1348 bool "Emulate SETEND instruction"
1349 help
1350 The SETEND instruction alters the data-endianness of the
1351 AArch32 EL0, and is deprecated in ARMv8.
1352
1353 Say Y here to enable software emulation of the instruction
dd720784
MB
1354 for AArch32 userspace code. This feature can be controlled
1355 at runtime with the abi.setend sysctl.
2d888f48
SP
1356
1357 Note: All the cpus on the system must have mixed endian support at EL0
1358 for this feature to be enabled. If a new CPU - which doesn't support mixed
1359 endian - is hotplugged in after this feature has been enabled, there could
1360 be unexpected results in the applications.
1361
1362 If unsure, say Y
1b907f46
WD
1363endif
1364
dd523791 1365endif
ba42822a 1366
0e4a0709
WD
1367menu "ARMv8.1 architectural features"
1368
1369config ARM64_HW_AFDBM
1370 bool "Support for hardware updates of the Access and Dirty page flags"
1371 default y
1372 help
1373 The ARMv8.1 architecture extensions introduce support for
1374 hardware updates of the access and dirty information in page
1375 table entries. When enabled in TCR_EL1 (HA and HD bits) on
1376 capable processors, accesses to pages with PTE_AF cleared will
1377 set this bit instead of raising an access flag fault.
1378 Similarly, writes to read-only pages with the DBM bit set will
1379 clear the read-only bit (AP[2]) instead of raising a
1380 permission fault.
1381
1382 Kernels built with this configuration option enabled continue
1383 to work on pre-ARMv8.1 hardware and the performance impact is
1384 minimal. If unsure, say Y.
1385
1386config ARM64_PAN
1387 bool "Enable support for Privileged Access Never (PAN)"
1388 default y
1389 help
1390 Privileged Access Never (PAN; part of the ARMv8.1 Extensions)
1391 prevents the kernel or hypervisor from accessing user-space (EL0)
1392 memory directly.
1393
1394 Choosing this option will cause any unprotected (not using
1395 copy_to_user et al) memory access to fail with a permission fault.
1396
1397 The feature is detected at runtime, and will remain as a 'nop'
1398 instruction if the cpu does not implement the feature.
1399
364a5a8a
WD
1400config AS_HAS_LDAPR
1401 def_bool $(as-instr,.arch_extension rcpc)
1402
2decad92
CM
1403config AS_HAS_LSE_ATOMICS
1404 def_bool $(as-instr,.arch_extension lse)
1405
0e4a0709 1406config ARM64_LSE_ATOMICS
395af861
CM
1407 bool
1408 default ARM64_USE_LSE_ATOMICS
2decad92 1409 depends on AS_HAS_LSE_ATOMICS
395af861
CM
1410
1411config ARM64_USE_LSE_ATOMICS
0e4a0709 1412 bool "Atomic instructions"
b32baf91 1413 depends on JUMP_LABEL
7bd99b40 1414 default y
0e4a0709
WD
1415 help
1416 As part of the Large System Extensions, ARMv8.1 introduces new
1417 atomic instructions that are designed specifically to scale in
1418 very large systems.
1419
1420 Say Y here to make use of these instructions for the in-kernel
1421 atomic routines. This incurs a small overhead on CPUs that do
1422 not support these instructions and requires the kernel to be
7bd99b40
WD
1423 built with binutils >= 2.25 in order for the new instructions
1424 to be used.
0e4a0709
WD
1425
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
1479 help
1480 Pointer authentication (part of the ARMv8.3 Extensions) provides
1481 instructions for signing and authenticating pointers against secret
1482 keys, which can be used to mitigate Return Oriented Programming (ROP)
1483 and other attacks.
1484
1485 This option enables these instructions at EL0 (i.e. for userspace).
04ca3204
MR
1486 Choosing this option will cause the kernel to initialise secret keys
1487 for each process at exec() time, with these keys being
1488 context-switched along with the process.
1489
1490 The feature is detected at runtime. If the feature is not present in
384b40ca 1491 hardware it will not be advertised to userspace/KVM guest nor will it
dfb0589c 1492 be enabled.
04ca3204 1493
6982934e
KM
1494 If the feature is present on the boot CPU but not on a late CPU, then
1495 the late CPU will be parked. Also, if the boot CPU does not have
1496 address auth and the late CPU has then the late CPU will still boot
1497 but with the feature disabled. On such a system, this option should
1498 not be selected.
1499
b27a9f41 1500config ARM64_PTR_AUTH_KERNEL
d053e71a 1501 bool "Use pointer authentication for kernel"
b27a9f41
DK
1502 default y
1503 depends on ARM64_PTR_AUTH
1504 depends on (CC_HAS_SIGN_RETURN_ADDRESS || CC_HAS_BRANCH_PROT_PAC_RET) && AS_HAS_PAC
1505 # Modern compilers insert a .note.gnu.property section note for PAC
1506 # which is only understood by binutils starting with version 2.33.1.
1507 depends on LD_IS_LLD || LD_VERSION >= 23301 || (CC_IS_GCC && GCC_VERSION < 90100)
1508 depends on !CC_IS_CLANG || AS_HAS_CFI_NEGATE_RA_STATE
1509 depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_REGS)
1510 help
1511 If the compiler supports the -mbranch-protection or
1512 -msign-return-address flag (e.g. GCC 7 or later), then this option
1513 will cause the kernel itself to be compiled with return address
1514 protection. In this case, and if the target hardware is known to
1515 support pointer authentication, then CONFIG_STACKPROTECTOR can be
1516 disabled with minimal loss of protection.
1517
74afda40
KM
1518 This feature works with FUNCTION_GRAPH_TRACER option only if
1519 DYNAMIC_FTRACE_WITH_REGS is enabled.
1520
1521config CC_HAS_BRANCH_PROT_PAC_RET
1522 # GCC 9 or later, clang 8 or later
1523 def_bool $(cc-option,-mbranch-protection=pac-ret+leaf)
1524
1525config CC_HAS_SIGN_RETURN_ADDRESS
1526 # GCC 7, 8
1527 def_bool $(cc-option,-msign-return-address=all)
1528
1529config AS_HAS_PAC
4d0831e8 1530 def_bool $(cc-option,-Wa$(comma)-march=armv8.3-a)
74afda40 1531
3b446c7d
ND
1532config AS_HAS_CFI_NEGATE_RA_STATE
1533 def_bool $(as-instr,.cfi_startproc\n.cfi_negate_ra_state\n.cfi_endproc\n)
1534
04ca3204
MR
1535endmenu
1536
2c9d45b4
IV
1537menu "ARMv8.4 architectural features"
1538
1539config ARM64_AMU_EXTN
1540 bool "Enable support for the Activity Monitors Unit CPU extension"
1541 default y
1542 help
1543 The activity monitors extension is an optional extension introduced
1544 by the ARMv8.4 CPU architecture. This enables support for version 1
1545 of the activity monitors architecture, AMUv1.
1546
1547 To enable the use of this extension on CPUs that implement it, say Y.
1548
1549 Note that for architectural reasons, firmware _must_ implement AMU
1550 support when running on CPUs that present the activity monitors
1551 extension. The required support is present in:
1552 * Version 1.5 and later of the ARM Trusted Firmware
1553
1554 For kernels that have this configuration enabled but boot with broken
1555 firmware, you may need to say N here until the firmware is fixed.
1556 Otherwise you may experience firmware panics or lockups when
1557 accessing the counter registers. Even if you are not observing these
1558 symptoms, the values returned by the register reads might not
1559 correctly reflect reality. Most commonly, the value read will be 0,
1560 indicating that the counter is not enabled.
1561
7c78f67e
ZY
1562config AS_HAS_ARMV8_4
1563 def_bool $(cc-option,-Wa$(comma)-march=armv8.4-a)
1564
1565config ARM64_TLB_RANGE
1566 bool "Enable support for tlbi range feature"
1567 default y
1568 depends on AS_HAS_ARMV8_4
1569 help
1570 ARMv8.4-TLBI provides TLBI invalidation instruction that apply to a
1571 range of input addresses.
1572
1573 The feature introduces new assembly instructions, and they were
1574 support when binutils >= 2.30.
1575
04ca3204
MR
1576endmenu
1577
3e6c69a0
MB
1578menu "ARMv8.5 architectural features"
1579
f469c032
VF
1580config AS_HAS_ARMV8_5
1581 def_bool $(cc-option,-Wa$(comma)-march=armv8.5-a)
1582
383499f8
DM
1583config ARM64_BTI
1584 bool "Branch Target Identification support"
1585 default y
1586 help
1587 Branch Target Identification (part of the ARMv8.5 Extensions)
1588 provides a mechanism to limit the set of locations to which computed
1589 branch instructions such as BR or BLR can jump.
1590
1591 To make use of BTI on CPUs that support it, say Y.
1592
1593 BTI is intended to provide complementary protection to other control
1594 flow integrity protection mechanisms, such as the Pointer
1595 authentication mechanism provided as part of the ARMv8.3 Extensions.
1596 For this reason, it does not make sense to enable this option without
1597 also enabling support for pointer authentication. Thus, when
1598 enabling this option you should also select ARM64_PTR_AUTH=y.
1599
1600 Userspace binaries must also be specifically compiled to make use of
1601 this mechanism. If you say N here or the hardware does not support
1602 BTI, such binaries can still run, but you get no additional
1603 enforcement of branch destinations.
1604
97fed779
MB
1605config ARM64_BTI_KERNEL
1606 bool "Use Branch Target Identification for kernel"
1607 default y
1608 depends on ARM64_BTI
b27a9f41 1609 depends on ARM64_PTR_AUTH_KERNEL
97fed779 1610 depends on CC_HAS_BRANCH_PROT_PAC_RET_BTI
3a88d7c5
WD
1611 # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94697
1612 depends on !CC_IS_GCC || GCC_VERSION >= 100100
8cdd23c2
NC
1613 # https://github.com/llvm/llvm-project/commit/a88c722e687e6780dcd6a58718350dc76fcc4cc9
1614 depends on !CC_IS_CLANG || CLANG_VERSION >= 120000
97fed779
MB
1615 depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_REGS)
1616 help
1617 Build the kernel with Branch Target Identification annotations
1618 and enable enforcement of this for kernel code. When this option
1619 is enabled and the system supports BTI all kernel code including
1620 modular code must have BTI enabled.
1621
1622config CC_HAS_BRANCH_PROT_PAC_RET_BTI
1623 # GCC 9 or later, clang 8 or later
1624 def_bool $(cc-option,-mbranch-protection=pac-ret+leaf+bti)
1625
3e6c69a0
MB
1626config ARM64_E0PD
1627 bool "Enable support for E0PD"
1628 default y
1629 help
e717d93b
WD
1630 E0PD (part of the ARMv8.5 extensions) allows us to ensure
1631 that EL0 accesses made via TTBR1 always fault in constant time,
1632 providing similar benefits to KASLR as those provided by KPTI, but
1633 with lower overhead and without disrupting legitimate access to
1634 kernel memory such as SPE.
3e6c69a0 1635
e717d93b 1636 This option enables E0PD for TTBR1 where available.
3e6c69a0 1637
1a50ec0b
RH
1638config ARCH_RANDOM
1639 bool "Enable support for random number generation"
1640 default y
1641 help
1642 Random number generation (part of the ARMv8.5 Extensions)
1643 provides a high bandwidth, cryptographically secure
1644 hardware random number generator.
1645
89b94df9
VF
1646config ARM64_AS_HAS_MTE
1647 # Initial support for MTE went in binutils 2.32.0, checked with
1648 # ".arch armv8.5-a+memtag" below. However, this was incomplete
1649 # as a late addition to the final architecture spec (LDGM/STGM)
1650 # is only supported in the newer 2.32.x and 2.33 binutils
1651 # versions, hence the extra "stgm" instruction check below.
1652 def_bool $(as-instr,.arch armv8.5-a+memtag\nstgm xzr$(comma)[x0])
1653
1654config ARM64_MTE
1655 bool "Memory Tagging Extension support"
1656 default y
1657 depends on ARM64_AS_HAS_MTE && ARM64_TAGGED_ADDR_ABI
f469c032 1658 depends on AS_HAS_ARMV8_5
2decad92 1659 depends on AS_HAS_LSE_ATOMICS
98c970da
VF
1660 # Required for tag checking in the uaccess routines
1661 depends on ARM64_PAN
89b94df9
VF
1662 select ARCH_USES_HIGH_VMA_FLAGS
1663 help
1664 Memory Tagging (part of the ARMv8.5 Extensions) provides
1665 architectural support for run-time, always-on detection of
1666 various classes of memory error to aid with software debugging
1667 to eliminate vulnerabilities arising from memory-unsafe
1668 languages.
1669
1670 This option enables the support for the Memory Tagging
1671 Extension at EL0 (i.e. for userspace).
1672
1673 Selecting this option allows the feature to be detected at
1674 runtime. Any secondary CPU not implementing this feature will
1675 not be allowed a late bring-up.
1676
1677 Userspace binaries that want to use this feature must
1678 explicitly opt in. The mechanism for the userspace is
1679 described in:
1680
1681 Documentation/arm64/memory-tagging-extension.rst.
1682
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MB
1683endmenu
1684
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VM
1685menu "ARMv8.7 architectural features"
1686
1687config ARM64_EPAN
1688 bool "Enable support for Enhanced Privileged Access Never (EPAN)"
1689 default y
1690 depends on ARM64_PAN
1691 help
1692 Enhanced Privileged Access Never (EPAN) allows Privileged
1693 Access Never to be used with Execute-only mappings.
1694
1695 The feature is detected at runtime, and will remain disabled
1696 if the cpu does not implement the feature.
1697endmenu
1698
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DM
1699config ARM64_SVE
1700 bool "ARM Scalable Vector Extension support"
1701 default y
1702 help
1703 The Scalable Vector Extension (SVE) is an extension to the AArch64
1704 execution state which complements and extends the SIMD functionality
1705 of the base architecture to support much larger vectors and to enable
1706 additional vectorisation opportunities.
1707
1708 To enable use of this extension on CPUs that implement it, say Y.
1709
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1710 On CPUs that support the SVE2 extensions, this option will enable
1711 those too.
1712
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1713 Note that for architectural reasons, firmware _must_ implement SVE
1714 support when running on SVE capable hardware. The required support
1715 is present in:
1716
1717 * version 1.5 and later of the ARM Trusted Firmware
1718 * the AArch64 boot wrapper since commit 5e1261e08abf
1719 ("bootwrapper: SVE: Enable SVE for EL2 and below").
1720
1721 For other firmware implementations, consult the firmware documentation
1722 or vendor.
1723
1724 If you need the kernel to boot on SVE-capable hardware with broken
1725 firmware, you may need to say N here until you get your firmware
1726 fixed. Otherwise, you may experience firmware panics or lockups when
1727 booting the kernel. If unsure and you are not observing these
1728 symptoms, you should assume that it is safe to say Y.
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1729
1730config ARM64_MODULE_PLTS
58557e48 1731 bool "Use PLTs to allow module memory to spill over into vmalloc area"
faaa73bc 1732 depends on MODULES
fd045f6c 1733 select HAVE_MOD_ARCH_SPECIFIC
58557e48
FF
1734 help
1735 Allocate PLTs when loading modules so that jumps and calls whose
1736 targets are too far away for their relative offsets to be encoded
1737 in the instructions themselves can be bounced via veneers in the
1738 module's PLT. This allows modules to be allocated in the generic
1739 vmalloc area after the dedicated module memory area has been
1740 exhausted.
1741
1742 When running with address space randomization (KASLR), the module
1743 region itself may be too far away for ordinary relative jumps and
1744 calls, and so in that case, module PLTs are required and cannot be
1745 disabled.
1746
1747 Specific errata workaround(s) might also force module PLTs to be
1748 enabled (ARM64_ERRATUM_843419).
fd045f6c 1749
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JT
1750config ARM64_PSEUDO_NMI
1751 bool "Support for NMI-like interrupts"
3c9c1dcd 1752 select ARM_GIC_V3
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JT
1753 help
1754 Adds support for mimicking Non-Maskable Interrupts through the use of
1755 GIC interrupt priority. This support requires version 3 or later of
bc15cf70 1756 ARM GIC.
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JT
1757
1758 This high priority configuration for interrupts needs to be
1759 explicitly enabled by setting the kernel parameter
1760 "irqchip.gicv3_pseudo_nmi" to 1.
1761
1762 If unsure, say N
1763
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JT
1764if ARM64_PSEUDO_NMI
1765config ARM64_DEBUG_PRIORITY_MASKING
1766 bool "Debug interrupt priority masking"
1767 help
1768 This adds runtime checks to functions enabling/disabling
1769 interrupts when using priority masking. The additional checks verify
1770 the validity of ICC_PMR_EL1 when calling concerned functions.
1771
1772 If unsure, say N
1773endif
1774
1e48ef7f 1775config RELOCATABLE
dd4bc607 1776 bool "Build a relocatable kernel image" if EXPERT
5cf896fb 1777 select ARCH_HAS_RELR
dd4bc607 1778 default y
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AB
1779 help
1780 This builds the kernel as a Position Independent Executable (PIE),
1781 which retains all relocation metadata required to relocate the
1782 kernel binary at runtime to a different virtual address than the
1783 address it was linked at.
1784 Since AArch64 uses the RELA relocation format, this requires a
1785 relocation pass at runtime even if the kernel is loaded at the
1786 same address it was linked at.
1787
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AB
1788config RANDOMIZE_BASE
1789 bool "Randomize the address of the kernel image"
b9c220b5 1790 select ARM64_MODULE_PLTS if MODULES
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AB
1791 select RELOCATABLE
1792 help
1793 Randomizes the virtual address at which the kernel image is
1794 loaded, as a security feature that deters exploit attempts
1795 relying on knowledge of the location of kernel internals.
1796
1797 It is the bootloader's job to provide entropy, by passing a
1798 random u64 value in /chosen/kaslr-seed at kernel entry.
1799
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1800 When booting via the UEFI stub, it will invoke the firmware's
1801 EFI_RNG_PROTOCOL implementation (if available) to supply entropy
1802 to the kernel proper. In addition, it will randomise the physical
1803 location of the kernel Image as well.
1804
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AB
1805 If unsure, say N.
1806
1807config RANDOMIZE_MODULE_REGION_FULL
f9c4ff2a 1808 bool "Randomize the module region over a 2 GB range"
e71a4e1b 1809 depends on RANDOMIZE_BASE
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AB
1810 default y
1811 help
f9c4ff2a 1812 Randomizes the location of the module region inside a 2 GB window
f2b9ba87 1813 covering the core kernel. This way, it is less likely for modules
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AB
1814 to leak information about the location of core kernel data structures
1815 but it does imply that function calls between modules and the core
1816 kernel will need to be resolved via veneers in the module PLT.
1817
1818 When this option is not set, the module region will be randomized over
1819 a limited range that contains the [_stext, _etext] interval of the
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BS
1820 core kernel, so branch relocations are almost always in range unless
1821 ARM64_MODULE_PLTS is enabled and the region is exhausted. In this
1822 particular case of region exhaustion, modules might be able to fall
1823 back to a larger 2GB area.
f80fb3a3 1824
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1825config CC_HAVE_STACKPROTECTOR_SYSREG
1826 def_bool $(cc-option,-mstack-protector-guard=sysreg -mstack-protector-guard-reg=sp_el0 -mstack-protector-guard-offset=0)
1827
1828config STACKPROTECTOR_PER_TASK
1829 def_bool y
1830 depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_SYSREG
1831
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CM
1832endmenu
1833
1834menu "Boot options"
1835
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1836config ARM64_ACPI_PARKING_PROTOCOL
1837 bool "Enable support for the ARM64 ACPI parking protocol"
1838 depends on ACPI
1839 help
1840 Enable support for the ARM64 ACPI parking protocol. If disabled
1841 the kernel will not allow booting through the ARM64 ACPI parking
1842 protocol even if the corresponding data is present in the ACPI
1843 MADT table.
1844
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CM
1845config CMDLINE
1846 string "Default kernel command string"
1847 default ""
1848 help
1849 Provide a set of default command-line options at build time by
1850 entering them here. As a minimum, you should specify the the
1851 root device (e.g. root=/dev/nfs).
1852
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TH
1853choice
1854 prompt "Kernel command line type" if CMDLINE != ""
1855 default CMDLINE_FROM_BOOTLOADER
1856 help
1857 Choose how the kernel will handle the provided default kernel
1858 command line string.
1859
1860config CMDLINE_FROM_BOOTLOADER
1861 bool "Use bootloader kernel arguments if available"
1862 help
1863 Uses the command-line options passed by the boot loader. If
1864 the boot loader doesn't provide any, the default kernel command
1865 string provided in CMDLINE will be used.
1866
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CM
1867config CMDLINE_FORCE
1868 bool "Always use the default kernel command string"
1869 help
1870 Always use the default kernel command string, even if the boot
1871 loader passes other arguments to the kernel.
1872 This is useful if you cannot or don't want to change the
1873 command-line options your boot loader passes to the kernel.
1874
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TH
1875endchoice
1876
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AB
1877config EFI_STUB
1878 bool
1879
f84d0275
MS
1880config EFI
1881 bool "UEFI runtime support"
1882 depends on OF && !CPU_BIG_ENDIAN
b472db6c 1883 depends on KERNEL_MODE_NEON
2c870e61 1884 select ARCH_SUPPORTS_ACPI
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MS
1885 select LIBFDT
1886 select UCS2_STRING
1887 select EFI_PARAMS_FROM_FDT
e15dd494 1888 select EFI_RUNTIME_WRAPPERS
f4f75ad5 1889 select EFI_STUB
2e0eb483 1890 select EFI_GENERIC_STUB
8d39cee0 1891 imply IMA_SECURE_AND_OR_TRUSTED_BOOT
f84d0275
MS
1892 default y
1893 help
1894 This option provides support for runtime services provided
1895 by UEFI firmware (such as non-volatile variables, realtime
3c7f2550
MS
1896 clock, and platform reset). A UEFI stub is also provided to
1897 allow the kernel to be booted as an EFI application. This
1898 is only useful on systems that have UEFI firmware.
f84d0275 1899
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YL
1900config DMI
1901 bool "Enable support for SMBIOS (DMI) tables"
1902 depends on EFI
1903 default y
1904 help
1905 This enables SMBIOS/DMI feature for systems.
1906
1907 This option is only useful on systems that have UEFI firmware.
1908 However, even with this option, the resultant kernel should
1909 continue to boot on existing non-UEFI platforms.
1910
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CM
1911endmenu
1912
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CM
1913config SYSVIPC_COMPAT
1914 def_bool y
1915 depends on COMPAT && SYSVIPC
1916
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LP
1917menu "Power management options"
1918
1919source "kernel/power/Kconfig"
1920
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JM
1921config ARCH_HIBERNATION_POSSIBLE
1922 def_bool y
1923 depends on CPU_PM
1924
1925config ARCH_HIBERNATION_HEADER
1926 def_bool y
1927 depends on HIBERNATION
1928
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LP
1929config ARCH_SUSPEND_POSSIBLE
1930 def_bool y
1931
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LP
1932endmenu
1933
1307220d
LP
1934menu "CPU Power Management"
1935
1936source "drivers/cpuidle/Kconfig"
1937
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RH
1938source "drivers/cpufreq/Kconfig"
1939
1940endmenu
1941
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GG
1942source "drivers/acpi/Kconfig"
1943
c3eb5b14
MZ
1944source "arch/arm64/kvm/Kconfig"
1945
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AB
1946if CRYPTO
1947source "arch/arm64/crypto/Kconfig"
1948endif