drm/meson: Fix overflow implicit truncation warnings
[linux-block.git] / arch / arm64 / Kconfig
CommitLineData
ec8f24b7 1# SPDX-License-Identifier: GPL-2.0-only
8c2c3df3
CM
2config ARM64
3 def_bool y
b6197b93 4 select ACPI_CCA_REQUIRED if ACPI
d8f4f161 5 select ACPI_GENERIC_GSI if ACPI
5f1ae4eb 6 select ACPI_GTDT if ACPI
c6bb8f89 7 select ACPI_IORT if ACPI
6933de0c 8 select ACPI_REDUCED_HARDWARE_ONLY if ACPI
52146173 9 select ACPI_MCFG if (ACPI && PCI)
888125a7 10 select ACPI_SPCR_TABLE if ACPI
0ce82232 11 select ACPI_PPTT if ACPI
09587a09 12 select ARCH_HAS_DEBUG_WX
6dd8b1a0 13 select ARCH_BINFMT_ELF_EXTRA_PHDRS
ab7876a9 14 select ARCH_BINFMT_ELF_STATE
cd9bc2c9 15 select ARCH_CORRECT_STACKTRACE_ON_KRETPROBE
1e866974 16 select ARCH_ENABLE_HUGEPAGE_MIGRATION if HUGETLB_PAGE && MIGRATION
91024b3c
AK
17 select ARCH_ENABLE_MEMORY_HOTPLUG
18 select ARCH_ENABLE_MEMORY_HOTREMOVE
66f24fa7 19 select ARCH_ENABLE_SPLIT_PMD_PTLOCK if PGTABLE_LEVELS > 2
1e866974 20 select ARCH_ENABLE_THP_MIGRATION if TRANSPARENT_HUGEPAGE
c2280be8 21 select ARCH_HAS_CACHE_LINE_SIZE
2792d84e 22 select ARCH_HAS_CURRENT_STACK_POINTER
ec6d06ef 23 select ARCH_HAS_DEBUG_VIRTUAL
399145f9 24 select ARCH_HAS_DEBUG_VM_PGTABLE
13bf5ced 25 select ARCH_HAS_DMA_PREP_COHERENT
38b04a74 26 select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI
e75bef2a 27 select ARCH_HAS_FAST_MULTIPLIER
6974f0c4 28 select ARCH_HAS_FORTIFY_SOURCE
957e3fac 29 select ARCH_HAS_GCOV_PROFILE_ALL
4eb0716e 30 select ARCH_HAS_GIGANTIC_PAGE
5e4c7549 31 select ARCH_HAS_KCOV
d8ae8a37 32 select ARCH_HAS_KEEPINITRD
f1e3a12b 33 select ARCH_HAS_MEMBARRIER_SYNC_CORE
0ebeea8c 34 select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
73b20c84 35 select ARCH_HAS_PTE_DEVMAP
3010a5ea 36 select ARCH_HAS_PTE_SPECIAL
347cb6af 37 select ARCH_HAS_SETUP_DMA_OPS
4739d53f 38 select ARCH_HAS_SET_DIRECT_MAP
d2852a22 39 select ARCH_HAS_SET_MEMORY
5fc57df2 40 select ARCH_STACKWALK
ad21fc4f
LA
41 select ARCH_HAS_STRICT_KERNEL_RWX
42 select ARCH_HAS_STRICT_MODULE_RWX
886643b7
CH
43 select ARCH_HAS_SYNC_DMA_FOR_DEVICE
44 select ARCH_HAS_SYNC_DMA_FOR_CPU
4378a7d4 45 select ARCH_HAS_SYSCALL_WRAPPER
dc2acded 46 select ARCH_HAS_TEARDOWN_DMA_OPS if IOMMU_SUPPORT
1f85008e 47 select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
b3aca728 48 select ARCH_HAS_VM_GET_PAGE_PROT
63703f37 49 select ARCH_HAS_ZONE_DMA_SET if EXPERT
ab7876a9 50 select ARCH_HAVE_ELF_PROT
396a5d4a 51 select ARCH_HAVE_NMI_SAFE_CMPXCHG
7ef858da
TG
52 select ARCH_INLINE_READ_LOCK if !PREEMPTION
53 select ARCH_INLINE_READ_LOCK_BH if !PREEMPTION
54 select ARCH_INLINE_READ_LOCK_IRQ if !PREEMPTION
55 select ARCH_INLINE_READ_LOCK_IRQSAVE if !PREEMPTION
56 select ARCH_INLINE_READ_UNLOCK if !PREEMPTION
57 select ARCH_INLINE_READ_UNLOCK_BH if !PREEMPTION
58 select ARCH_INLINE_READ_UNLOCK_IRQ if !PREEMPTION
59 select ARCH_INLINE_READ_UNLOCK_IRQRESTORE if !PREEMPTION
60 select ARCH_INLINE_WRITE_LOCK if !PREEMPTION
61 select ARCH_INLINE_WRITE_LOCK_BH if !PREEMPTION
62 select ARCH_INLINE_WRITE_LOCK_IRQ if !PREEMPTION
63 select ARCH_INLINE_WRITE_LOCK_IRQSAVE if !PREEMPTION
64 select ARCH_INLINE_WRITE_UNLOCK if !PREEMPTION
65 select ARCH_INLINE_WRITE_UNLOCK_BH if !PREEMPTION
66 select ARCH_INLINE_WRITE_UNLOCK_IRQ if !PREEMPTION
67 select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE if !PREEMPTION
68 select ARCH_INLINE_SPIN_TRYLOCK if !PREEMPTION
69 select ARCH_INLINE_SPIN_TRYLOCK_BH if !PREEMPTION
70 select ARCH_INLINE_SPIN_LOCK if !PREEMPTION
71 select ARCH_INLINE_SPIN_LOCK_BH if !PREEMPTION
72 select ARCH_INLINE_SPIN_LOCK_IRQ if !PREEMPTION
73 select ARCH_INLINE_SPIN_LOCK_IRQSAVE if !PREEMPTION
74 select ARCH_INLINE_SPIN_UNLOCK if !PREEMPTION
75 select ARCH_INLINE_SPIN_UNLOCK_BH if !PREEMPTION
76 select ARCH_INLINE_SPIN_UNLOCK_IRQ if !PREEMPTION
77 select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE if !PREEMPTION
350e88ba 78 select ARCH_KEEP_MEMBLOCK
c63c8700 79 select ARCH_USE_CMPXCHG_LOCKREF
bf7f15c5 80 select ARCH_USE_GNU_PROPERTY
dce44566 81 select ARCH_USE_MEMTEST
087133ac 82 select ARCH_USE_QUEUED_RWLOCKS
c1109047 83 select ARCH_USE_QUEUED_SPINLOCKS
50479d58 84 select ARCH_USE_SYM_ANNOTATIONS
5d6ad668 85 select ARCH_SUPPORTS_DEBUG_PAGEALLOC
855f9a8e 86 select ARCH_SUPPORTS_HUGETLBFS
c484f256 87 select ARCH_SUPPORTS_MEMORY_FAILURE
5287569a 88 select ARCH_SUPPORTS_SHADOW_CALL_STACK if CC_HAVE_SHADOW_CALL_STACK
112b6a8e
ST
89 select ARCH_SUPPORTS_LTO_CLANG if CPU_LITTLE_ENDIAN
90 select ARCH_SUPPORTS_LTO_CLANG_THIN
9186ad8e 91 select ARCH_SUPPORTS_CFI_CLANG
4badad35 92 select ARCH_SUPPORTS_ATOMIC_RMW
42a7ba16 93 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
56166230 94 select ARCH_SUPPORTS_NUMA_BALANCING
42b25471 95 select ARCH_SUPPORTS_PAGE_TABLE_CHECK
84c187af 96 select ARCH_WANT_COMPAT_IPC_PARSE_VERSION if COMPAT
81c22041 97 select ARCH_WANT_DEFAULT_BPF_JIT
67f3977f 98 select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT
b6f35981 99 select ARCH_WANT_FRAME_POINTERS
3876d4a3 100 select ARCH_WANT_HUGE_PMD_SHARE if ARM64_4K_PAGES || (ARM64_16K_PAGES && !ARM64_VA_BITS_36)
47010c04 101 select ARCH_WANT_HUGETLB_PAGE_OPTIMIZE_VMEMMAP
59612b24 102 select ARCH_WANT_LD_ORPHAN_WARN
51c2ee6d 103 select ARCH_WANTS_NO_INSTR
f0b7f8a4 104 select ARCH_HAS_UBSAN_SANITIZE_ALL
25c92a37 105 select ARM_AMBA
1aee5d7a 106 select ARM_ARCH_TIMER
c4188edc 107 select ARM_GIC
875cbf3e 108 select AUDIT_ARCH_COMPAT_GENERIC
3ee80364 109 select ARM_GIC_V2M if PCI
021f6537 110 select ARM_GIC_V3
3ee80364 111 select ARM_GIC_V3_ITS if PCI
bff60792 112 select ARM_PSCI_FW
10916706 113 select BUILDTIME_TABLE_SORT
db2789b5 114 select CLONE_BACKWARDS
7ca2ef33 115 select COMMON_CLK
166936ba 116 select CPU_PM if (SUSPEND || CPU_IDLE)
7481cddf 117 select CRC32
7bc13fd3 118 select DCACHE_WORD_ACCESS
0c3b3171 119 select DMA_DIRECT_REMAP
ef37566c 120 select EDAC_SUPPORT
2f34f173 121 select FRAME_POINTER
d4932f9e 122 select GENERIC_ALLOCATOR
2ef7a295 123 select GENERIC_ARCH_TOPOLOGY
4b3dc967 124 select GENERIC_CLOCKEVENTS_BROADCAST
3be1a5c4 125 select GENERIC_CPU_AUTOPROBE
61ae1321 126 select GENERIC_CPU_VULNERABILITIES
bf4b558e 127 select GENERIC_EARLY_IOREMAP
2314ee4d 128 select GENERIC_IDLE_POLL_SETUP
d3afc7f1 129 select GENERIC_IRQ_IPI
8c2c3df3
CM
130 select GENERIC_IRQ_PROBE
131 select GENERIC_IRQ_SHOW
6544e67b 132 select GENERIC_IRQ_SHOW_LEVEL
6585bd82 133 select GENERIC_LIB_DEVMEM_IS_ALLOWED
cb61f676 134 select GENERIC_PCI_IOMAP
102f45fd 135 select GENERIC_PTDUMP
65cd4f6c 136 select GENERIC_SCHED_CLOCK
8c2c3df3
CM
137 select GENERIC_SMP_IDLE_THREAD
138 select GENERIC_TIME_VSYSCALL
28b1a824 139 select GENERIC_GETTIMEOFDAY
9614cc57 140 select GENERIC_VDSO_TIME_NS
8c2c3df3 141 select HARDIRQS_SW_RESEND
45544eee 142 select HAVE_MOVE_PMD
f5308c89 143 select HAVE_MOVE_PUD
eb01d42a 144 select HAVE_PCI
9f9a35a7 145 select HAVE_ACPI_APEI if (ACPI && EFI)
5284e1b4 146 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
875cbf3e 147 select HAVE_ARCH_AUDITSYSCALL
8e7a4cef 148 select HAVE_ARCH_BITREVERSE
689eae42 149 select HAVE_ARCH_COMPILER_H
324420bf 150 select HAVE_ARCH_HUGE_VMAP
9732cafd 151 select HAVE_ARCH_JUMP_LABEL
c296146c 152 select HAVE_ARCH_JUMP_LABEL_RELATIVE
e17d8025 153 select HAVE_ARCH_KASAN if !(ARM64_16K_PAGES && ARM64_VA_BITS_48)
71b613fc 154 select HAVE_ARCH_KASAN_VMALLOC if HAVE_ARCH_KASAN
2d4acb90 155 select HAVE_ARCH_KASAN_SW_TAGS if HAVE_ARCH_KASAN
94ab5b61 156 select HAVE_ARCH_KASAN_HW_TAGS if (HAVE_ARCH_KASAN && ARM64_MTE)
dd03762a
KW
157 # Some instrumentation may be unsound, hence EXPERT
158 select HAVE_ARCH_KCSAN if EXPERT
840b2398 159 select HAVE_ARCH_KFENCE
9529247d 160 select HAVE_ARCH_KGDB
8f0d3aa9
DC
161 select HAVE_ARCH_MMAP_RND_BITS
162 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT
271ca788 163 select HAVE_ARCH_PREL32_RELOCATIONS
70918779 164 select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET
a1ae65b2 165 select HAVE_ARCH_SECCOMP_FILTER
0b3e3366 166 select HAVE_ARCH_STACKLEAK
9e8084d3 167 select HAVE_ARCH_THREAD_STRUCT_WHITELIST
8c2c3df3 168 select HAVE_ARCH_TRACEHOOK
8ee70879 169 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
e3067861 170 select HAVE_ARCH_VMAP_STACK
8ee70879 171 select HAVE_ARM_SMCCC
2ff2b7ec 172 select HAVE_ASM_MODVERSIONS
6077776b 173 select HAVE_EBPF_JIT
af64d2aa 174 select HAVE_C_RECORDMCOUNT
5284e1b4 175 select HAVE_CMPXCHG_DOUBLE
95eff6b2 176 select HAVE_CMPXCHG_LOCAL
8ee70879 177 select HAVE_CONTEXT_TRACKING
b69ec42b 178 select HAVE_DEBUG_KMEMLEAK
6ac2104d 179 select HAVE_DMA_CONTIGUOUS
bd7d38db 180 select HAVE_DYNAMIC_FTRACE
a31d793d
ST
181 select FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY \
182 if DYNAMIC_FTRACE_WITH_REGS
50afc33a 183 select HAVE_EFFICIENT_UNALIGNED_ACCESS
67a929e0 184 select HAVE_FAST_GUP
af64d2aa 185 select HAVE_FTRACE_MCOUNT_RECORD
819e50e2 186 select HAVE_FUNCTION_TRACER
42d038c4 187 select HAVE_FUNCTION_ERROR_INJECTION
819e50e2 188 select HAVE_FUNCTION_GRAPH_TRACER
6b90bd4b 189 select HAVE_GCC_PLUGINS
8c2c3df3 190 select HAVE_HW_BREAKPOINT if PERF_EVENTS
24da208d 191 select HAVE_IRQ_TIME_ACCOUNTING
e26bb75a 192 select HAVE_KVM
396a5d4a 193 select HAVE_NMI
55834a77 194 select HAVE_PATA_PLATFORM
8c2c3df3 195 select HAVE_PERF_EVENTS
2ee0d7fd
JP
196 select HAVE_PERF_REGS
197 select HAVE_PERF_USER_STACK_DUMP
1b2d3451 198 select HAVE_PREEMPT_DYNAMIC_KEY
0a8ea52c 199 select HAVE_REGS_AND_STACK_ACCESS_API
a68773bd 200 select HAVE_POSIX_CPU_TIMERS_TASK_WORK
a823c35f 201 select HAVE_FUNCTION_ARG_ACCESS_API
ff2e6d72 202 select MMU_GATHER_RCU_TABLE_FREE
409d5db4 203 select HAVE_RSEQ
d148eac0 204 select HAVE_STACKPROTECTOR
055b1212 205 select HAVE_SYSCALL_TRACEPOINTS
2dd0e8d2 206 select HAVE_KPROBES
cd1ee3b1 207 select HAVE_KRETPROBES
28b1a824 208 select HAVE_GENERIC_VDSO
876945db 209 select IOMMU_DMA if IOMMU_SUPPORT
8c2c3df3 210 select IRQ_DOMAIN
e8557d1f 211 select IRQ_FORCED_THREADING
f6f37d93 212 select KASAN_VMALLOC if KASAN
fea2acaa 213 select MODULES_USE_ELF_RELA
f616ab59 214 select NEED_DMA_MAP_STATE
86596f0a 215 select NEED_SG_DMA_LENGTH
8c2c3df3
CM
216 select OF
217 select OF_EARLY_FLATTREE
2eac9c2d 218 select PCI_DOMAINS_GENERIC if PCI
52146173 219 select PCI_ECAM if (ACPI && PCI)
20f1b79d 220 select PCI_SYSCALL if PCI
aa1e8ec1
CM
221 select POWER_RESET
222 select POWER_SUPPLY
8c2c3df3 223 select SPARSE_IRQ
09230cbc 224 select SWIOTLB
7ac57a89 225 select SYSCTL_EXCEPTION_TRACE
c02433dd 226 select THREAD_INFO_IN_TASK
7677f7fd 227 select HAVE_ARCH_USERFAULTFD_MINOR if USERFAULTFD
4aae683f 228 select TRACE_IRQFLAGS_SUPPORT
8c2c3df3
CM
229 help
230 ARM 64-bit (AArch64) Linux support.
231
45bd8951
NC
232config CLANG_SUPPORTS_DYNAMIC_FTRACE_WITH_REGS
233 def_bool CC_IS_CLANG
234 # https://github.com/ClangBuiltLinux/linux/issues/1507
235 depends on AS_IS_GNU || (AS_IS_LLVM && (LD_IS_LLD || LD_VERSION >= 23600))
236 select HAVE_DYNAMIC_FTRACE_WITH_REGS
237
238config GCC_SUPPORTS_DYNAMIC_FTRACE_WITH_REGS
239 def_bool CC_IS_GCC
240 depends on $(cc-option,-fpatchable-function-entry=2)
241 select HAVE_DYNAMIC_FTRACE_WITH_REGS
242
8c2c3df3
CM
243config 64BIT
244 def_bool y
245
8c2c3df3
CM
246config MMU
247 def_bool y
248
030c4d24
MR
249config ARM64_PAGE_SHIFT
250 int
251 default 16 if ARM64_64K_PAGES
252 default 14 if ARM64_16K_PAGES
253 default 12
254
c0d6de32 255config ARM64_CONT_PTE_SHIFT
030c4d24
MR
256 int
257 default 5 if ARM64_64K_PAGES
258 default 7 if ARM64_16K_PAGES
259 default 4
260
e6765941
GS
261config ARM64_CONT_PMD_SHIFT
262 int
263 default 5 if ARM64_64K_PAGES
264 default 5 if ARM64_16K_PAGES
265 default 4
266
8f0d3aa9 267config ARCH_MMAP_RND_BITS_MIN
3cb7e662
JH
268 default 14 if ARM64_64K_PAGES
269 default 16 if ARM64_16K_PAGES
270 default 18
8f0d3aa9
DC
271
272# max bits determined by the following formula:
273# VA_BITS - PAGE_SHIFT - 3
274config ARCH_MMAP_RND_BITS_MAX
3cb7e662
JH
275 default 19 if ARM64_VA_BITS=36
276 default 24 if ARM64_VA_BITS=39
277 default 27 if ARM64_VA_BITS=42
278 default 30 if ARM64_VA_BITS=47
279 default 29 if ARM64_VA_BITS=48 && ARM64_64K_PAGES
280 default 31 if ARM64_VA_BITS=48 && ARM64_16K_PAGES
281 default 33 if ARM64_VA_BITS=48
282 default 14 if ARM64_64K_PAGES
283 default 16 if ARM64_16K_PAGES
284 default 18
8f0d3aa9
DC
285
286config ARCH_MMAP_RND_COMPAT_BITS_MIN
3cb7e662
JH
287 default 7 if ARM64_64K_PAGES
288 default 9 if ARM64_16K_PAGES
289 default 11
8f0d3aa9
DC
290
291config ARCH_MMAP_RND_COMPAT_BITS_MAX
3cb7e662 292 default 16
8f0d3aa9 293
ce816fa8 294config NO_IOPORT_MAP
d1e6dc91 295 def_bool y if !PCI
8c2c3df3
CM
296
297config STACKTRACE_SUPPORT
298 def_bool y
299
bf0c4e04
JVS
300config ILLEGAL_POINTER_VALUE
301 hex
302 default 0xdead000000000000
303
8c2c3df3
CM
304config LOCKDEP_SUPPORT
305 def_bool y
306
9fb7410f
DM
307config GENERIC_BUG
308 def_bool y
309 depends on BUG
310
311config GENERIC_BUG_RELATIVE_POINTERS
312 def_bool y
313 depends on GENERIC_BUG
314
8c2c3df3
CM
315config GENERIC_HWEIGHT
316 def_bool y
317
318config GENERIC_CSUM
3cb7e662 319 def_bool y
8c2c3df3
CM
320
321config GENERIC_CALIBRATE_DELAY
322 def_bool y
323
ca6e51d5
OS
324config ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE
325 def_bool y
326
4b3dc967
WD
327config SMP
328 def_bool y
329
4cfb3613
AB
330config KERNEL_MODE_NEON
331 def_bool y
332
92cc15fc
RH
333config FIX_EARLYCON_MEM
334 def_bool y
335
9f25e6ad
KS
336config PGTABLE_LEVELS
337 int
21539939 338 default 2 if ARM64_16K_PAGES && ARM64_VA_BITS_36
9f25e6ad 339 default 2 if ARM64_64K_PAGES && ARM64_VA_BITS_42
b6d00d47 340 default 3 if ARM64_64K_PAGES && (ARM64_VA_BITS_48 || ARM64_VA_BITS_52)
9f25e6ad 341 default 3 if ARM64_4K_PAGES && ARM64_VA_BITS_39
44eaacf1
SP
342 default 3 if ARM64_16K_PAGES && ARM64_VA_BITS_47
343 default 4 if !ARM64_64K_PAGES && ARM64_VA_BITS_48
9f25e6ad 344
9842ceae
PA
345config ARCH_SUPPORTS_UPROBES
346 def_bool y
347
8f360948
AB
348config ARCH_PROC_KCORE_TEXT
349 def_bool y
350
8bf9284d
VM
351config BROKEN_GAS_INST
352 def_bool !$(as-instr,1:\n.inst 0\n.rept . - 1b\n\nnop\n.endr\n)
353
6bd1d0be
SC
354config KASAN_SHADOW_OFFSET
355 hex
0fea6e9a 356 depends on KASAN_GENERIC || KASAN_SW_TAGS
f4693c27
AB
357 default 0xdfff800000000000 if (ARM64_VA_BITS_48 || ARM64_VA_BITS_52) && !KASAN_SW_TAGS
358 default 0xdfffc00000000000 if ARM64_VA_BITS_47 && !KASAN_SW_TAGS
359 default 0xdffffe0000000000 if ARM64_VA_BITS_42 && !KASAN_SW_TAGS
360 default 0xdfffffc000000000 if ARM64_VA_BITS_39 && !KASAN_SW_TAGS
361 default 0xdffffff800000000 if ARM64_VA_BITS_36 && !KASAN_SW_TAGS
362 default 0xefff800000000000 if (ARM64_VA_BITS_48 || ARM64_VA_BITS_52) && KASAN_SW_TAGS
363 default 0xefffc00000000000 if ARM64_VA_BITS_47 && KASAN_SW_TAGS
364 default 0xeffffe0000000000 if ARM64_VA_BITS_42 && KASAN_SW_TAGS
365 default 0xefffffc000000000 if ARM64_VA_BITS_39 && KASAN_SW_TAGS
366 default 0xeffffff800000000 if ARM64_VA_BITS_36 && KASAN_SW_TAGS
6bd1d0be
SC
367 default 0xffffffffffffffff
368
6a377491 369source "arch/arm64/Kconfig.platforms"
8c2c3df3 370
8c2c3df3
CM
371menu "Kernel Features"
372
c0a01b84
AP
373menu "ARM errata workarounds via the alternatives framework"
374
c9460dcb 375config ARM64_WORKAROUND_CLEAN_CACHE
bc15cf70 376 bool
c9460dcb 377
c0a01b84
AP
378config ARM64_ERRATUM_826319
379 bool "Cortex-A53: 826319: System might deadlock if a write cannot complete until read data is accepted"
380 default y
c9460dcb 381 select ARM64_WORKAROUND_CLEAN_CACHE
c0a01b84
AP
382 help
383 This option adds an alternative code sequence to work around ARM
384 erratum 826319 on Cortex-A53 parts up to r0p2 with an AMBA 4 ACE or
385 AXI master interface and an L2 cache.
386
387 If a Cortex-A53 uses an AMBA AXI4 ACE interface to other processors
388 and is unable to accept a certain write via this interface, it will
389 not progress on read data presented on the read data channel and the
390 system can deadlock.
391
392 The workaround promotes data cache clean instructions to
393 data cache clean-and-invalidate.
394 Please note that this does not necessarily enable the workaround,
395 as it depends on the alternative framework, which will only patch
396 the kernel if an affected CPU is detected.
397
398 If unsure, say Y.
399
400config ARM64_ERRATUM_827319
401 bool "Cortex-A53: 827319: Data cache clean instructions might cause overlapping transactions to the interconnect"
402 default y
c9460dcb 403 select ARM64_WORKAROUND_CLEAN_CACHE
c0a01b84
AP
404 help
405 This option adds an alternative code sequence to work around ARM
406 erratum 827319 on Cortex-A53 parts up to r0p2 with an AMBA 5 CHI
407 master interface and an L2 cache.
408
409 Under certain conditions this erratum can cause a clean line eviction
410 to occur at the same time as another transaction to the same address
411 on the AMBA 5 CHI interface, which can cause data corruption if the
412 interconnect reorders the two transactions.
413
414 The workaround promotes data cache clean instructions to
415 data cache clean-and-invalidate.
416 Please note that this does not necessarily enable the workaround,
417 as it depends on the alternative framework, which will only patch
418 the kernel if an affected CPU is detected.
419
420 If unsure, say Y.
421
422config ARM64_ERRATUM_824069
423 bool "Cortex-A53: 824069: Cache line might not be marked as clean after a CleanShared snoop"
424 default y
c9460dcb 425 select ARM64_WORKAROUND_CLEAN_CACHE
c0a01b84
AP
426 help
427 This option adds an alternative code sequence to work around ARM
428 erratum 824069 on Cortex-A53 parts up to r0p2 when it is connected
429 to a coherent interconnect.
430
431 If a Cortex-A53 processor is executing a store or prefetch for
432 write instruction at the same time as a processor in another
433 cluster is executing a cache maintenance operation to the same
434 address, then this erratum might cause a clean cache line to be
435 incorrectly marked as dirty.
436
437 The workaround promotes data cache clean instructions to
438 data cache clean-and-invalidate.
439 Please note that this option does not necessarily enable the
440 workaround, as it depends on the alternative framework, which will
441 only patch the kernel if an affected CPU is detected.
442
443 If unsure, say Y.
444
445config ARM64_ERRATUM_819472
446 bool "Cortex-A53: 819472: Store exclusive instructions might cause data corruption"
447 default y
c9460dcb 448 select ARM64_WORKAROUND_CLEAN_CACHE
c0a01b84
AP
449 help
450 This option adds an alternative code sequence to work around ARM
451 erratum 819472 on Cortex-A53 parts up to r0p1 with an L2 cache
452 present when it is connected to a coherent interconnect.
453
454 If the processor is executing a load and store exclusive sequence at
455 the same time as a processor in another cluster is executing a cache
456 maintenance operation to the same address, then this erratum might
457 cause data corruption.
458
459 The workaround promotes data cache clean instructions to
460 data cache clean-and-invalidate.
461 Please note that this does not necessarily enable the workaround,
462 as it depends on the alternative framework, which will only patch
463 the kernel if an affected CPU is detected.
464
465 If unsure, say Y.
466
467config ARM64_ERRATUM_832075
468 bool "Cortex-A57: 832075: possible deadlock on mixing exclusive memory accesses with device loads"
469 default y
470 help
471 This option adds an alternative code sequence to work around ARM
472 erratum 832075 on Cortex-A57 parts up to r1p2.
473
474 Affected Cortex-A57 parts might deadlock when exclusive load/store
475 instructions to Write-Back memory are mixed with Device loads.
476
477 The workaround is to promote device loads to use Load-Acquire
478 semantics.
479 Please note that this does not necessarily enable the workaround,
498cd5c3
MZ
480 as it depends on the alternative framework, which will only patch
481 the kernel if an affected CPU is detected.
482
483 If unsure, say Y.
484
485config ARM64_ERRATUM_834220
486 bool "Cortex-A57: 834220: Stage 2 translation fault might be incorrectly reported in presence of a Stage 1 fault"
487 depends on KVM
488 default y
489 help
490 This option adds an alternative code sequence to work around ARM
491 erratum 834220 on Cortex-A57 parts up to r1p2.
492
493 Affected Cortex-A57 parts might report a Stage 2 translation
494 fault as the result of a Stage 1 fault for load crossing a
495 page boundary when there is a permission or device memory
496 alignment fault at Stage 1 and a translation fault at Stage 2.
497
498 The workaround is to verify that the Stage 1 translation
499 doesn't generate a fault before handling the Stage 2 fault.
500 Please note that this does not necessarily enable the workaround,
c0a01b84
AP
501 as it depends on the alternative framework, which will only patch
502 the kernel if an affected CPU is detected.
503
504 If unsure, say Y.
505
905e8c5d
WD
506config ARM64_ERRATUM_845719
507 bool "Cortex-A53: 845719: a load might read incorrect data"
508 depends on COMPAT
509 default y
510 help
511 This option adds an alternative code sequence to work around ARM
512 erratum 845719 on Cortex-A53 parts up to r0p4.
513
514 When running a compat (AArch32) userspace on an affected Cortex-A53
515 part, a load at EL0 from a virtual address that matches the bottom 32
516 bits of the virtual address used by a recent load at (AArch64) EL1
517 might return incorrect data.
518
519 The workaround is to write the contextidr_el1 register on exception
520 return to a 32-bit task.
521 Please note that this does not necessarily enable the workaround,
522 as it depends on the alternative framework, which will only patch
523 the kernel if an affected CPU is detected.
524
525 If unsure, say Y.
526
df057cc7
WD
527config ARM64_ERRATUM_843419
528 bool "Cortex-A53: 843419: A load or store might access an incorrect address"
df057cc7 529 default y
a257e025 530 select ARM64_MODULE_PLTS if MODULES
df057cc7 531 help
6ffe9923 532 This option links the kernel with '--fix-cortex-a53-843419' and
a257e025
AB
533 enables PLT support to replace certain ADRP instructions, which can
534 cause subsequent memory accesses to use an incorrect address on
535 Cortex-A53 parts up to r0p4.
df057cc7
WD
536
537 If unsure, say Y.
538
987fdfec
MY
539config ARM64_LD_HAS_FIX_ERRATUM_843419
540 def_bool $(ld-option,--fix-cortex-a53-843419)
541
ece1397c
SP
542config ARM64_ERRATUM_1024718
543 bool "Cortex-A55: 1024718: Update of DBM/AP bits without break before make might result in incorrect update"
544 default y
545 help
bc15cf70 546 This option adds a workaround for ARM Cortex-A55 Erratum 1024718.
ece1397c 547
c0b15c25 548 Affected Cortex-A55 cores (all revisions) could cause incorrect
ece1397c 549 update of the hardware dirty bit when the DBM/AP bits are updated
bc15cf70 550 without a break-before-make. The workaround is to disable the usage
ece1397c 551 of hardware DBM locally on the affected cores. CPUs not affected by
bc15cf70 552 this erratum will continue to use the feature.
df057cc7
WD
553
554 If unsure, say Y.
555
a5325089 556config ARM64_ERRATUM_1418040
6989303a 557 bool "Cortex-A76/Neoverse-N1: MRC read following MRRC read of specific Generic Timer in AArch32 might give incorrect result"
95b861a4 558 default y
c2b5bba3 559 depends on COMPAT
95b861a4 560 help
24cf262d 561 This option adds a workaround for ARM Cortex-A76/Neoverse-N1
a5325089 562 errata 1188873 and 1418040.
95b861a4 563
a5325089 564 Affected Cortex-A76/Neoverse-N1 cores (r0p0 to r3p1) could
6989303a
MZ
565 cause register corruption when accessing the timer registers
566 from AArch32 userspace.
95b861a4
MZ
567
568 If unsure, say Y.
569
02ab1f50 570config ARM64_WORKAROUND_SPECULATIVE_AT
e85d68fa
SP
571 bool
572
a457b0f7 573config ARM64_ERRATUM_1165522
02ab1f50 574 bool "Cortex-A76: 1165522: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
a457b0f7 575 default y
02ab1f50 576 select ARM64_WORKAROUND_SPECULATIVE_AT
a457b0f7 577 help
bc15cf70 578 This option adds a workaround for ARM Cortex-A76 erratum 1165522.
a457b0f7
MZ
579
580 Affected Cortex-A76 cores (r0p0, r1p0, r2p0) could end-up with
581 corrupted TLBs by speculating an AT instruction during a guest
582 context switch.
583
584 If unsure, say Y.
585
02ab1f50
AS
586config ARM64_ERRATUM_1319367
587 bool "Cortex-A57/A72: 1319537: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
588 default y
589 select ARM64_WORKAROUND_SPECULATIVE_AT
590 help
591 This option adds work arounds for ARM Cortex-A57 erratum 1319537
592 and A72 erratum 1319367
593
594 Cortex-A57 and A72 cores could end-up with corrupted TLBs by
595 speculating an AT instruction during a guest context switch.
596
597 If unsure, say Y.
598
275fa0ea 599config ARM64_ERRATUM_1530923
02ab1f50 600 bool "Cortex-A55: 1530923: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
275fa0ea 601 default y
02ab1f50 602 select ARM64_WORKAROUND_SPECULATIVE_AT
275fa0ea
SP
603 help
604 This option adds a workaround for ARM Cortex-A55 erratum 1530923.
605
606 Affected Cortex-A55 cores (r0p0, r0p1, r1p0, r2p0) could end-up with
607 corrupted TLBs by speculating an AT instruction during a guest
608 context switch.
609
610 If unsure, say Y.
a457b0f7 611
ebcea694
GU
612config ARM64_WORKAROUND_REPEAT_TLBI
613 bool
614
ce8c80c5
CM
615config ARM64_ERRATUM_1286807
616 bool "Cortex-A76: Modification of the translation table for a virtual address might lead to read-after-read ordering violation"
617 default y
618 select ARM64_WORKAROUND_REPEAT_TLBI
619 help
bc15cf70 620 This option adds a workaround for ARM Cortex-A76 erratum 1286807.
ce8c80c5
CM
621
622 On the affected Cortex-A76 cores (r0p0 to r3p0), if a virtual
623 address for a cacheable mapping of a location is being
624 accessed by a core while another core is remapping the virtual
625 address to a new physical page using the recommended
626 break-before-make sequence, then under very rare circumstances
627 TLBI+DSB completes before a read using the translation being
628 invalidated has been observed by other observers. The
629 workaround repeats the TLBI+DSB operation.
630
969f5ea6
WD
631config ARM64_ERRATUM_1463225
632 bool "Cortex-A76: Software Step might prevent interrupt recognition"
633 default y
634 help
635 This option adds a workaround for Arm Cortex-A76 erratum 1463225.
636
637 On the affected Cortex-A76 cores (r0p0 to r3p1), software stepping
638 of a system call instruction (SVC) can prevent recognition of
639 subsequent interrupts when software stepping is disabled in the
640 exception handler of the system call and either kernel debugging
641 is enabled or VHE is in use.
642
643 Work around the erratum by triggering a dummy step exception
644 when handling a system call from a task that is being stepped
645 in a VHE configuration of the kernel.
646
647 If unsure, say Y.
648
05460849
JM
649config ARM64_ERRATUM_1542419
650 bool "Neoverse-N1: workaround mis-ordering of instruction fetches"
651 default y
652 help
653 This option adds a workaround for ARM Neoverse-N1 erratum
654 1542419.
655
656 Affected Neoverse-N1 cores could execute a stale instruction when
657 modified by another CPU. The workaround depends on a firmware
658 counterpart.
659
660 Workaround the issue by hiding the DIC feature from EL0. This
661 forces user-space to perform cache maintenance.
662
663 If unsure, say Y.
664
96d389ca
RH
665config ARM64_ERRATUM_1508412
666 bool "Cortex-A77: 1508412: workaround deadlock on sequence of NC/Device load and store exclusive or PAR read"
667 default y
668 help
669 This option adds a workaround for Arm Cortex-A77 erratum 1508412.
670
671 Affected Cortex-A77 cores (r0p0, r1p0) could deadlock on a sequence
672 of a store-exclusive or read of PAR_EL1 and a load with device or
673 non-cacheable memory attributes. The workaround depends on a firmware
674 counterpart.
675
676 KVM guests must also have the workaround implemented or they can
677 deadlock the system.
678
679 Work around the issue by inserting DMB SY barriers around PAR_EL1
680 register reads and warning KVM users. The DMB barrier is sufficient
681 to prevent a speculative PAR_EL1 read.
682
683 If unsure, say Y.
684
b9d216fc
SP
685config ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
686 bool
687
297ae1eb
JM
688config ARM64_ERRATUM_2051678
689 bool "Cortex-A510: 2051678: disable Hardware Update of the page table dirty bit"
a4b92ceb 690 default y
297ae1eb
JM
691 help
692 This options adds the workaround for ARM Cortex-A510 erratum ARM64_ERRATUM_2051678.
0ff74a23 693 Affected Cortex-A510 might not respect the ordering rules for
297ae1eb
JM
694 hardware update of the page table's dirty bit. The workaround
695 is to not enable the feature on affected CPUs.
696
697 If unsure, say Y.
698
1dd498e5
JM
699config ARM64_ERRATUM_2077057
700 bool "Cortex-A510: 2077057: workaround software-step corrupting SPSR_EL2"
4c11113c 701 default y
1dd498e5
JM
702 help
703 This option adds the workaround for ARM Cortex-A510 erratum 2077057.
704 Affected Cortex-A510 may corrupt SPSR_EL2 when the a step exception is
705 expected, but a Pointer Authentication trap is taken instead. The
706 erratum causes SPSR_EL1 to be copied to SPSR_EL2, which could allow
707 EL1 to cause a return to EL2 with a guest controlled ELR_EL2.
708
709 This can only happen when EL2 is stepping EL1.
710
711 When these conditions occur, the SPSR_EL2 value is unchanged from the
712 previous guest entry, and can be restored from the in-memory copy.
713
714 If unsure, say Y.
715
b9d216fc 716config ARM64_ERRATUM_2119858
eb30d838 717 bool "Cortex-A710/X2: 2119858: workaround TRBE overwriting trace data in FILL mode"
b9d216fc 718 default y
b9d216fc
SP
719 depends on CORESIGHT_TRBE
720 select ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
721 help
eb30d838 722 This option adds the workaround for ARM Cortex-A710/X2 erratum 2119858.
b9d216fc 723
eb30d838 724 Affected Cortex-A710/X2 cores could overwrite up to 3 cache lines of trace
b9d216fc
SP
725 data at the base of the buffer (pointed to by TRBASER_EL1) in FILL mode in
726 the event of a WRAP event.
727
728 Work around the issue by always making sure we move the TRBPTR_EL1 by
729 256 bytes before enabling the buffer and filling the first 256 bytes of
730 the buffer with ETM ignore packets upon disabling.
731
732 If unsure, say Y.
733
734config ARM64_ERRATUM_2139208
735 bool "Neoverse-N2: 2139208: workaround TRBE overwriting trace data in FILL mode"
736 default y
b9d216fc
SP
737 depends on CORESIGHT_TRBE
738 select ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
739 help
740 This option adds the workaround for ARM Neoverse-N2 erratum 2139208.
741
742 Affected Neoverse-N2 cores could overwrite up to 3 cache lines of trace
743 data at the base of the buffer (pointed to by TRBASER_EL1) in FILL mode in
744 the event of a WRAP event.
745
746 Work around the issue by always making sure we move the TRBPTR_EL1 by
747 256 bytes before enabling the buffer and filling the first 256 bytes of
748 the buffer with ETM ignore packets upon disabling.
749
750 If unsure, say Y.
751
fa82d0b4
SP
752config ARM64_WORKAROUND_TSB_FLUSH_FAILURE
753 bool
754
755config ARM64_ERRATUM_2054223
756 bool "Cortex-A710: 2054223: workaround TSB instruction failing to flush trace"
757 default y
758 select ARM64_WORKAROUND_TSB_FLUSH_FAILURE
759 help
760 Enable workaround for ARM Cortex-A710 erratum 2054223
761
762 Affected cores may fail to flush the trace data on a TSB instruction, when
763 the PE is in trace prohibited state. This will cause losing a few bytes
764 of the trace cached.
765
766 Workaround is to issue two TSB consecutively on affected cores.
767
768 If unsure, say Y.
769
770config ARM64_ERRATUM_2067961
771 bool "Neoverse-N2: 2067961: workaround TSB instruction failing to flush trace"
772 default y
773 select ARM64_WORKAROUND_TSB_FLUSH_FAILURE
774 help
775 Enable workaround for ARM Neoverse-N2 erratum 2067961
776
777 Affected cores may fail to flush the trace data on a TSB instruction, when
778 the PE is in trace prohibited state. This will cause losing a few bytes
779 of the trace cached.
780
781 Workaround is to issue two TSB consecutively on affected cores.
782
783 If unsure, say Y.
784
8d81b2a3
SP
785config ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE
786 bool
787
788config ARM64_ERRATUM_2253138
789 bool "Neoverse-N2: 2253138: workaround TRBE writing to address out-of-range"
8d81b2a3
SP
790 depends on CORESIGHT_TRBE
791 default y
792 select ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE
793 help
794 This option adds the workaround for ARM Neoverse-N2 erratum 2253138.
795
796 Affected Neoverse-N2 cores might write to an out-of-range address, not reserved
797 for TRBE. Under some conditions, the TRBE might generate a write to the next
798 virtually addressed page following the last page of the TRBE address space
799 (i.e., the TRBLIMITR_EL1.LIMIT), instead of wrapping around to the base.
800
801 Work around this in the driver by always making sure that there is a
802 page beyond the TRBLIMITR_EL1.LIMIT, within the space allowed for the TRBE.
803
804 If unsure, say Y.
805
806config ARM64_ERRATUM_2224489
eb30d838 807 bool "Cortex-A710/X2: 2224489: workaround TRBE writing to address out-of-range"
8d81b2a3
SP
808 depends on CORESIGHT_TRBE
809 default y
810 select ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE
811 help
eb30d838 812 This option adds the workaround for ARM Cortex-A710/X2 erratum 2224489.
8d81b2a3 813
eb30d838 814 Affected Cortex-A710/X2 cores might write to an out-of-range address, not reserved
8d81b2a3
SP
815 for TRBE. Under some conditions, the TRBE might generate a write to the next
816 virtually addressed page following the last page of the TRBE address space
817 (i.e., the TRBLIMITR_EL1.LIMIT), instead of wrapping around to the base.
818
819 Work around this in the driver by always making sure that there is a
820 page beyond the TRBLIMITR_EL1.LIMIT, within the space allowed for the TRBE.
821
822 If unsure, say Y.
823
607a9afa
AK
824config ARM64_ERRATUM_2064142
825 bool "Cortex-A510: 2064142: workaround TRBE register writes while disabled"
ac0ba210 826 depends on CORESIGHT_TRBE
607a9afa
AK
827 default y
828 help
829 This option adds the workaround for ARM Cortex-A510 erratum 2064142.
830
831 Affected Cortex-A510 core might fail to write into system registers after the
832 TRBE has been disabled. Under some conditions after the TRBE has been disabled
833 writes into TRBE registers TRBLIMITR_EL1, TRBPTR_EL1, TRBBASER_EL1, TRBSR_EL1,
834 and TRBTRG_EL1 will be ignored and will not be effected.
835
836 Work around this in the driver by executing TSB CSYNC and DSB after collection
837 is stopped and before performing a system register write to one of the affected
838 registers.
839
840 If unsure, say Y.
841
3bd94a87
AK
842config ARM64_ERRATUM_2038923
843 bool "Cortex-A510: 2038923: workaround TRBE corruption with enable"
f209e9fe 844 depends on CORESIGHT_TRBE
3bd94a87
AK
845 default y
846 help
847 This option adds the workaround for ARM Cortex-A510 erratum 2038923.
848
849 Affected Cortex-A510 core might cause an inconsistent view on whether trace is
850 prohibited within the CPU. As a result, the trace buffer or trace buffer state
851 might be corrupted. This happens after TRBE buffer has been enabled by setting
852 TRBLIMITR_EL1.E, followed by just a single context synchronization event before
853 execution changes from a context, in which trace is prohibited to one where it
854 isn't, or vice versa. In these mentioned conditions, the view of whether trace
855 is prohibited is inconsistent between parts of the CPU, and the trace buffer or
856 the trace buffer state might be corrupted.
857
858 Work around this in the driver by preventing an inconsistent view of whether the
859 trace is prohibited or not based on TRBLIMITR_EL1.E by immediately following a
860 change to TRBLIMITR_EL1.E with at least one ISB instruction before an ERET, or
861 two ISB instructions if no ERET is to take place.
862
863 If unsure, say Y.
864
708e8af4
AK
865config ARM64_ERRATUM_1902691
866 bool "Cortex-A510: 1902691: workaround TRBE trace corruption"
3a828845 867 depends on CORESIGHT_TRBE
708e8af4
AK
868 default y
869 help
870 This option adds the workaround for ARM Cortex-A510 erratum 1902691.
871
872 Affected Cortex-A510 core might cause trace data corruption, when being written
873 into the memory. Effectively TRBE is broken and hence cannot be used to capture
874 trace data.
875
876 Work around this problem in the driver by just preventing TRBE initialization on
877 affected cpus. The firmware must have disabled the access to TRBE for the kernel
878 on such implementations. This will cover the kernel for any firmware that doesn't
879 do this already.
880
881 If unsure, say Y.
882
94100970
RR
883config CAVIUM_ERRATUM_22375
884 bool "Cavium erratum 22375, 24313"
885 default y
886 help
bc15cf70 887 Enable workaround for errata 22375 and 24313.
94100970
RR
888
889 This implements two gicv3-its errata workarounds for ThunderX. Both
bc15cf70 890 with a small impact affecting only ITS table allocation.
94100970
RR
891
892 erratum 22375: only alloc 8MB table size
893 erratum 24313: ignore memory access type
894
895 The fixes are in ITS initialization and basically ignore memory access
896 type and table size provided by the TYPER and BASER registers.
897
898 If unsure, say Y.
899
fbf8f40e
GK
900config CAVIUM_ERRATUM_23144
901 bool "Cavium erratum 23144: ITS SYNC hang on dual socket system"
902 depends on NUMA
903 default y
904 help
905 ITS SYNC command hang for cross node io and collections/cpu mapping.
906
907 If unsure, say Y.
908
6d4e11c5 909config CAVIUM_ERRATUM_23154
24a147bc 910 bool "Cavium errata 23154 and 38545: GICv3 lacks HW synchronisation"
6d4e11c5
RR
911 default y
912 help
24a147bc 913 The ThunderX GICv3 implementation requires a modified version for
6d4e11c5
RR
914 reading the IAR status to ensure data synchronization
915 (access to icc_iar1_el1 is not sync'ed before and after).
916
24a147bc
LC
917 It also suffers from erratum 38545 (also present on Marvell's
918 OcteonTX and OcteonTX2), resulting in deactivated interrupts being
919 spuriously presented to the CPU interface.
920
6d4e11c5
RR
921 If unsure, say Y.
922
104a0c02
AP
923config CAVIUM_ERRATUM_27456
924 bool "Cavium erratum 27456: Broadcast TLBI instructions may cause icache corruption"
925 default y
926 help
927 On ThunderX T88 pass 1.x through 2.1 parts, broadcast TLBI
928 instructions may cause the icache to become corrupted if it
929 contains data for a non-current ASID. The fix is to
930 invalidate the icache when changing the mm context.
931
932 If unsure, say Y.
933
690a3415
DD
934config CAVIUM_ERRATUM_30115
935 bool "Cavium erratum 30115: Guest may disable interrupts in host"
936 default y
937 help
938 On ThunderX T88 pass 1.x through 2.2, T81 pass 1.0 through
939 1.2, and T83 Pass 1.0, KVM guest execution may disable
940 interrupts in host. Trapping both GICv3 group-0 and group-1
941 accesses sidesteps the issue.
942
943 If unsure, say Y.
944
603afdc9
MZ
945config CAVIUM_TX2_ERRATUM_219
946 bool "Cavium ThunderX2 erratum 219: PRFM between TTBR change and ISB fails"
947 default y
948 help
949 On Cavium ThunderX2, a load, store or prefetch instruction between a
950 TTBR update and the corresponding context synchronizing operation can
951 cause a spurious Data Abort to be delivered to any hardware thread in
952 the CPU core.
953
954 Work around the issue by avoiding the problematic code sequence and
955 trapping KVM guest TTBRx_EL1 writes to EL2 when SMT is enabled. The
956 trap handler performs the corresponding register access, skips the
957 instruction and ensures context synchronization by virtue of the
958 exception return.
959
960 If unsure, say Y.
961
ebcea694
GU
962config FUJITSU_ERRATUM_010001
963 bool "Fujitsu-A64FX erratum E#010001: Undefined fault may occur wrongly"
964 default y
965 help
966 This option adds a workaround for Fujitsu-A64FX erratum E#010001.
967 On some variants of the Fujitsu-A64FX cores ver(1.0, 1.1), memory
968 accesses may cause undefined fault (Data abort, DFSC=0b111111).
969 This fault occurs under a specific hardware condition when a
970 load/store instruction performs an address translation using:
971 case-1 TTBR0_EL1 with TCR_EL1.NFD0 == 1.
972 case-2 TTBR0_EL2 with TCR_EL2.NFD0 == 1.
973 case-3 TTBR1_EL1 with TCR_EL1.NFD1 == 1.
974 case-4 TTBR1_EL2 with TCR_EL2.NFD1 == 1.
975
976 The workaround is to ensure these bits are clear in TCR_ELx.
977 The workaround only affects the Fujitsu-A64FX.
978
979 If unsure, say Y.
980
981config HISILICON_ERRATUM_161600802
982 bool "Hip07 161600802: Erroneous redistributor VLPI base"
983 default y
984 help
985 The HiSilicon Hip07 SoC uses the wrong redistributor base
986 when issued ITS commands such as VMOVP and VMAPP, and requires
987 a 128kB offset to be applied to the target address in this commands.
988
989 If unsure, say Y.
990
38fd94b0
CC
991config QCOM_FALKOR_ERRATUM_1003
992 bool "Falkor E1003: Incorrect translation due to ASID change"
993 default y
38fd94b0
CC
994 help
995 On Falkor v1, an incorrect ASID may be cached in the TLB when ASID
d1777e68
WD
996 and BADDR are changed together in TTBRx_EL1. Since we keep the ASID
997 in TTBR1_EL1, this situation only occurs in the entry trampoline and
998 then only for entries in the walk cache, since the leaf translation
999 is unchanged. Work around the erratum by invalidating the walk cache
1000 entries for the trampoline before entering the kernel proper.
38fd94b0 1001
d9ff80f8
CC
1002config QCOM_FALKOR_ERRATUM_1009
1003 bool "Falkor E1009: Prematurely complete a DSB after a TLBI"
1004 default y
ce8c80c5 1005 select ARM64_WORKAROUND_REPEAT_TLBI
d9ff80f8
CC
1006 help
1007 On Falkor v1, the CPU may prematurely complete a DSB following a
1008 TLBI xxIS invalidate maintenance operation. Repeat the TLBI operation
1009 one more time to fix the issue.
1010
1011 If unsure, say Y.
1012
90922a2d
SD
1013config QCOM_QDF2400_ERRATUM_0065
1014 bool "QDF2400 E0065: Incorrect GITS_TYPER.ITT_Entry_size"
1015 default y
1016 help
1017 On Qualcomm Datacenter Technologies QDF2400 SoC, ITS hardware reports
1018 ITE size incorrectly. The GITS_TYPER.ITT_Entry_size field should have
1019 been indicated as 16Bytes (0xf), not 8Bytes (0x7).
1020
1021 If unsure, say Y.
1022
932b50c7
SD
1023config QCOM_FALKOR_ERRATUM_E1041
1024 bool "Falkor E1041: Speculative instruction fetches might cause errant memory access"
1025 default y
1026 help
1027 Falkor CPU may speculatively fetch instructions from an improper
1028 memory location when MMU translation is changed from SCTLR_ELn[M]=1
1029 to SCTLR_ELn[M]=0. Prefix an ISB instruction to fix the problem.
1030
1031 If unsure, say Y.
1032
20109a85
RW
1033config NVIDIA_CARMEL_CNP_ERRATUM
1034 bool "NVIDIA Carmel CNP: CNP on Carmel semantically different than ARM cores"
1035 default y
1036 help
1037 If CNP is enabled on Carmel cores, non-sharable TLBIs on a core will not
1038 invalidate shared TLB entries installed by a different core, as it would
1039 on standard ARM cores.
1040
1041 If unsure, say Y.
1042
ebcea694
GU
1043config SOCIONEXT_SYNQUACER_PREITS
1044 bool "Socionext Synquacer: Workaround for GICv3 pre-ITS"
3e32131a
ZL
1045 default y
1046 help
ebcea694
GU
1047 Socionext Synquacer SoCs implement a separate h/w block to generate
1048 MSI doorbell writes with non-zero values for the device ID.
3e32131a
ZL
1049
1050 If unsure, say Y.
1051
3cb7e662 1052endmenu # "ARM errata workarounds via the alternatives framework"
c0a01b84 1053
e41ceed0
JL
1054choice
1055 prompt "Page size"
1056 default ARM64_4K_PAGES
1057 help
1058 Page size (translation granule) configuration.
1059
1060config ARM64_4K_PAGES
1061 bool "4KB"
1062 help
1063 This feature enables 4KB pages support.
1064
44eaacf1
SP
1065config ARM64_16K_PAGES
1066 bool "16KB"
1067 help
1068 The system will use 16KB pages support. AArch32 emulation
1069 requires applications compiled with 16K (or a multiple of 16K)
1070 aligned segments.
1071
8c2c3df3 1072config ARM64_64K_PAGES
e41ceed0 1073 bool "64KB"
8c2c3df3
CM
1074 help
1075 This feature enables 64KB pages support (4KB by default)
1076 allowing only two levels of page tables and faster TLB
db488be3
SP
1077 look-up. AArch32 emulation requires applications compiled
1078 with 64K aligned segments.
8c2c3df3 1079
e41ceed0
JL
1080endchoice
1081
1082choice
1083 prompt "Virtual address space size"
1084 default ARM64_VA_BITS_39 if ARM64_4K_PAGES
44eaacf1 1085 default ARM64_VA_BITS_47 if ARM64_16K_PAGES
e41ceed0
JL
1086 default ARM64_VA_BITS_42 if ARM64_64K_PAGES
1087 help
1088 Allows choosing one of multiple possible virtual address
1089 space sizes. The level of translation table is determined by
1090 a combination of page size and virtual address space size.
1091
21539939 1092config ARM64_VA_BITS_36
56a3f30e 1093 bool "36-bit" if EXPERT
21539939
SP
1094 depends on ARM64_16K_PAGES
1095
e41ceed0
JL
1096config ARM64_VA_BITS_39
1097 bool "39-bit"
1098 depends on ARM64_4K_PAGES
1099
1100config ARM64_VA_BITS_42
1101 bool "42-bit"
1102 depends on ARM64_64K_PAGES
1103
44eaacf1
SP
1104config ARM64_VA_BITS_47
1105 bool "47-bit"
1106 depends on ARM64_16K_PAGES
1107
c79b954b
JL
1108config ARM64_VA_BITS_48
1109 bool "48-bit"
c79b954b 1110
b6d00d47
SC
1111config ARM64_VA_BITS_52
1112 bool "52-bit"
68d23da4
WD
1113 depends on ARM64_64K_PAGES && (ARM64_PAN || !ARM64_SW_TTBR0_PAN)
1114 help
1115 Enable 52-bit virtual addressing for userspace when explicitly
b6d00d47
SC
1116 requested via a hint to mmap(). The kernel will also use 52-bit
1117 virtual addresses for its own mappings (provided HW support for
1118 this feature is available, otherwise it reverts to 48-bit).
68d23da4
WD
1119
1120 NOTE: Enabling 52-bit virtual addressing in conjunction with
1121 ARMv8.3 Pointer Authentication will result in the PAC being
1122 reduced from 7 bits to 3 bits, which may have a significant
1123 impact on its susceptibility to brute-force attacks.
1124
1125 If unsure, select 48-bit virtual addressing instead.
1126
e41ceed0
JL
1127endchoice
1128
68d23da4
WD
1129config ARM64_FORCE_52BIT
1130 bool "Force 52-bit virtual addresses for userspace"
b6d00d47 1131 depends on ARM64_VA_BITS_52 && EXPERT
68d23da4
WD
1132 help
1133 For systems with 52-bit userspace VAs enabled, the kernel will attempt
1134 to maintain compatibility with older software by providing 48-bit VAs
1135 unless a hint is supplied to mmap.
1136
1137 This configuration option disables the 48-bit compatibility logic, and
1138 forces all userspace addresses to be 52-bit on HW that supports it. One
1139 should only enable this configuration option for stress testing userspace
1140 memory management code. If unsure say N here.
1141
e41ceed0
JL
1142config ARM64_VA_BITS
1143 int
21539939 1144 default 36 if ARM64_VA_BITS_36
e41ceed0
JL
1145 default 39 if ARM64_VA_BITS_39
1146 default 42 if ARM64_VA_BITS_42
44eaacf1 1147 default 47 if ARM64_VA_BITS_47
b6d00d47
SC
1148 default 48 if ARM64_VA_BITS_48
1149 default 52 if ARM64_VA_BITS_52
e41ceed0 1150
982aa7c5
KM
1151choice
1152 prompt "Physical address space size"
1153 default ARM64_PA_BITS_48
1154 help
1155 Choose the maximum physical address range that the kernel will
1156 support.
1157
1158config ARM64_PA_BITS_48
1159 bool "48-bit"
1160
f77d2817
KM
1161config ARM64_PA_BITS_52
1162 bool "52-bit (ARMv8.2)"
1163 depends on ARM64_64K_PAGES
1164 depends on ARM64_PAN || !ARM64_SW_TTBR0_PAN
1165 help
1166 Enable support for a 52-bit physical address space, introduced as
1167 part of the ARMv8.2-LPA extension.
1168
1169 With this enabled, the kernel will also continue to work on CPUs that
1170 do not support ARMv8.2-LPA, but with some added memory overhead (and
1171 minor performance overhead).
1172
982aa7c5
KM
1173endchoice
1174
1175config ARM64_PA_BITS
1176 int
1177 default 48 if ARM64_PA_BITS_48
f77d2817 1178 default 52 if ARM64_PA_BITS_52
982aa7c5 1179
d8e85e14
AR
1180choice
1181 prompt "Endianness"
1182 default CPU_LITTLE_ENDIAN
1183 help
1184 Select the endianness of data accesses performed by the CPU. Userspace
1185 applications will need to be compiled and linked for the endianness
1186 that is selected here.
1187
a872013d 1188config CPU_BIG_ENDIAN
e9c6deee
NC
1189 bool "Build big-endian kernel"
1190 depends on !LD_IS_LLD || LLD_VERSION >= 130000
1191 help
d8e85e14
AR
1192 Say Y if you plan on running a kernel with a big-endian userspace.
1193
1194config CPU_LITTLE_ENDIAN
1195 bool "Build little-endian kernel"
1196 help
1197 Say Y if you plan on running a kernel with a little-endian userspace.
1198 This is usually the case for distributions targeting arm64.
1199
1200endchoice
a872013d 1201
f6e763b9
MB
1202config SCHED_MC
1203 bool "Multi-core scheduler support"
f6e763b9
MB
1204 help
1205 Multi-core scheduler support improves the CPU scheduler's decision
1206 making when dealing with multi-core CPU chips at a cost of slightly
1207 increased overhead in some places. If unsure say N here.
1208
778c558f
BS
1209config SCHED_CLUSTER
1210 bool "Cluster scheduler support"
1211 help
1212 Cluster scheduler support improves the CPU scheduler's decision
1213 making when dealing with machines that have clusters of CPUs.
1214 Cluster usually means a couple of CPUs which are placed closely
1215 by sharing mid-level caches, last-level cache tags or internal
1216 busses.
1217
f6e763b9
MB
1218config SCHED_SMT
1219 bool "SMT scheduler support"
f6e763b9
MB
1220 help
1221 Improves the CPU scheduler's decision making when dealing with
1222 MultiThreading at a cost of slightly increased overhead in some
1223 places. If unsure say N here.
1224
8c2c3df3 1225config NR_CPUS
62aa9655
GK
1226 int "Maximum number of CPUs (2-4096)"
1227 range 2 4096
846a415b 1228 default "256"
8c2c3df3 1229
9327e2c6
MR
1230config HOTPLUG_CPU
1231 bool "Support for hot-pluggable CPUs"
217d453d 1232 select GENERIC_IRQ_MIGRATION
9327e2c6
MR
1233 help
1234 Say Y here to experiment with turning CPUs off and on. CPUs
1235 can be controlled through /sys/devices/system/cpu.
1236
1a2db300
GK
1237# Common NUMA Features
1238config NUMA
4399e6cd 1239 bool "NUMA Memory Allocation and Scheduler Support"
ae3c107c 1240 select GENERIC_ARCH_NUMA
0c2a6cce
KW
1241 select ACPI_NUMA if ACPI
1242 select OF_NUMA
7ecd19cf
KW
1243 select HAVE_SETUP_PER_CPU_AREA
1244 select NEED_PER_CPU_EMBED_FIRST_CHUNK
1245 select NEED_PER_CPU_PAGE_FIRST_CHUNK
1246 select USE_PERCPU_NUMA_NODE_ID
1a2db300 1247 help
4399e6cd 1248 Enable NUMA (Non-Uniform Memory Access) support.
1a2db300
GK
1249
1250 The kernel will try to allocate memory used by a CPU on the
1251 local memory of the CPU and add some more
1252 NUMA awareness to the kernel.
1253
1254config NODES_SHIFT
1255 int "Maximum NUMA Nodes (as a power of 2)"
1256 range 1 10
2a13c13b 1257 default "4"
a9ee6cf5 1258 depends on NUMA
1a2db300
GK
1259 help
1260 Specify the maximum number of NUMA Nodes available on the target
1261 system. Increases memory reserved to accommodate various tables.
1262
8636a1f9 1263source "kernel/Kconfig.hz"
8c2c3df3 1264
8c2c3df3
CM
1265config ARCH_SPARSEMEM_ENABLE
1266 def_bool y
1267 select SPARSEMEM_VMEMMAP_ENABLE
782276b4 1268 select SPARSEMEM_VMEMMAP
e7d4bac4 1269
8c2c3df3 1270config HW_PERF_EVENTS
6475b2d8
MR
1271 def_bool y
1272 depends on ARM_PMU
8c2c3df3 1273
afcf5441 1274# Supported by clang >= 7.0 or GCC >= 12.0.0
5287569a
ST
1275config CC_HAVE_SHADOW_CALL_STACK
1276 def_bool $(cc-option, -fsanitize=shadow-call-stack -ffixed-x18)
1277
dfd57bc3
SS
1278config PARAVIRT
1279 bool "Enable paravirtualization code"
1280 help
1281 This changes the kernel so it can modify itself when it is run
1282 under a hypervisor, potentially improving performance significantly
1283 over full virtualization.
1284
1285config PARAVIRT_TIME_ACCOUNTING
1286 bool "Paravirtual steal time accounting"
1287 select PARAVIRT
dfd57bc3
SS
1288 help
1289 Select this option to enable fine granularity task steal time
1290 accounting. Time spent executing other tasks in parallel with
1291 the current vCPU is discounted from the vCPU power. To account for
1292 that, there can be a small performance impact.
1293
1294 If in doubt, say N here.
1295
d28f6df1
GL
1296config KEXEC
1297 depends on PM_SLEEP_SMP
1298 select KEXEC_CORE
1299 bool "kexec system call"
a7f7f624 1300 help
d28f6df1
GL
1301 kexec is a system call that implements the ability to shutdown your
1302 current kernel, and to start another kernel. It is like a reboot
1303 but it is independent of the system firmware. And like a reboot
1304 you can start any kernel with it, not just Linux.
1305
3ddd9992
AT
1306config KEXEC_FILE
1307 bool "kexec file based system call"
1308 select KEXEC_CORE
dce92f6b 1309 select HAVE_IMA_KEXEC if IMA
3ddd9992
AT
1310 help
1311 This is new version of kexec system call. This system call is
1312 file based and takes file descriptors as system call argument
1313 for kernel and initramfs as opposed to list of segments as
1314 accepted by previous system call.
1315
99d5cadf 1316config KEXEC_SIG
732b7b93
AT
1317 bool "Verify kernel signature during kexec_file_load() syscall"
1318 depends on KEXEC_FILE
1319 help
1320 Select this option to verify a signature with loaded kernel
1321 image. If configured, any attempt of loading a image without
1322 valid signature will fail.
1323
1324 In addition to that option, you need to enable signature
1325 verification for the corresponding kernel image type being
1326 loaded in order for this to work.
1327
1328config KEXEC_IMAGE_VERIFY_SIG
1329 bool "Enable Image signature verification support"
1330 default y
99d5cadf 1331 depends on KEXEC_SIG
732b7b93
AT
1332 depends on EFI && SIGNED_PE_FILE_VERIFICATION
1333 help
1334 Enable Image signature verification support.
1335
1336comment "Support for PE file signature verification disabled"
99d5cadf 1337 depends on KEXEC_SIG
732b7b93
AT
1338 depends on !EFI || !SIGNED_PE_FILE_VERIFICATION
1339
e62aaeac
AT
1340config CRASH_DUMP
1341 bool "Build kdump crash kernel"
1342 help
1343 Generate crash dump after being started by kexec. This should
1344 be normally only set in special crash dump kernels which are
1345 loaded in the main kernel with kexec-tools into a specially
1346 reserved region and then later executed after a crash by
1347 kdump/kexec.
1348
330d4810 1349 For more details see Documentation/admin-guide/kdump/kdump.rst
e62aaeac 1350
072e3d96
PT
1351config TRANS_TABLE
1352 def_bool y
08eae0ef 1353 depends on HIBERNATION || KEXEC_CORE
072e3d96 1354
aa42aa13
SS
1355config XEN_DOM0
1356 def_bool y
1357 depends on XEN
1358
1359config XEN
c2ba1f7d 1360 bool "Xen guest support on ARM64"
aa42aa13 1361 depends on ARM64 && OF
83862ccf 1362 select SWIOTLB_XEN
dfd57bc3 1363 select PARAVIRT
aa42aa13
SS
1364 help
1365 Say Y if you want to run Linux in a Virtual Machine on Xen on ARM64.
1366
d03bb145
SC
1367config FORCE_MAX_ZONEORDER
1368 int
79cc2ed5
AK
1369 default "14" if ARM64_64K_PAGES
1370 default "12" if ARM64_16K_PAGES
d03bb145 1371 default "11"
44eaacf1
SP
1372 help
1373 The kernel memory allocator divides physically contiguous memory
1374 blocks into "zones", where each zone is a power of two number of
1375 pages. This option selects the largest power of two that the kernel
1376 keeps in the memory allocator. If you need to allocate very large
1377 blocks of physically contiguous memory, then you may need to
1378 increase this value.
1379
1380 This config option is actually maximum order plus one. For example,
1381 a value of 11 means that the largest free memory block is 2^10 pages.
1382
1383 We make sure that we can allocate upto a HugePage size for each configuration.
1384 Hence we have :
1385 MAX_ORDER = (PMD_SHIFT - PAGE_SHIFT) + 1 => PAGE_SHIFT - 2
1386
1387 However for 4K, we choose a higher default value, 11 as opposed to 10, giving us
1388 4M allocations matching the default size used by generic code.
d03bb145 1389
084eb77c 1390config UNMAP_KERNEL_AT_EL0
0617052d 1391 bool "Unmap kernel when running in userspace (aka \"KAISER\")" if EXPERT
084eb77c
WD
1392 default y
1393 help
0617052d
WD
1394 Speculation attacks against some high-performance processors can
1395 be used to bypass MMU permission checks and leak kernel data to
1396 userspace. This can be defended against by unmapping the kernel
1397 when running in userspace, mapping it back in on exception entry
1398 via a trampoline page in the vector table.
084eb77c
WD
1399
1400 If unsure, say Y.
1401
558c303c
JM
1402config MITIGATE_SPECTRE_BRANCH_HISTORY
1403 bool "Mitigate Spectre style attacks against branch history" if EXPERT
1404 default y
1405 help
1406 Speculation attacks against some high-performance processors can
1407 make use of branch history to influence future speculation.
1408 When taking an exception from user-space, a sequence of branches
1409 or a firmware call overwrites the branch history.
1410
c55191e9
AB
1411config RODATA_FULL_DEFAULT_ENABLED
1412 bool "Apply r/o permissions of VM areas also to their linear aliases"
1413 default y
1414 help
1415 Apply read-only attributes of VM areas to the linear alias of
1416 the backing pages as well. This prevents code or read-only data
1417 from being modified (inadvertently or intentionally) via another
1418 mapping of the same memory page. This additional enhancement can
1419 be turned off at runtime by passing rodata=[off|on] (and turned on
1420 with rodata=full if this option is set to 'n')
1421
1422 This requires the linear region to be mapped down to pages,
1423 which may adversely affect performance in some cases.
1424
dd523791
WD
1425config ARM64_SW_TTBR0_PAN
1426 bool "Emulate Privileged Access Never using TTBR0_EL1 switching"
1427 help
1428 Enabling this option prevents the kernel from accessing
1429 user-space memory directly by pointing TTBR0_EL1 to a reserved
1430 zeroed area and reserved ASID. The user access routines
1431 restore the valid TTBR0_EL1 temporarily.
1432
63f0c603
CM
1433config ARM64_TAGGED_ADDR_ABI
1434 bool "Enable the tagged user addresses syscall ABI"
1435 default y
1436 help
1437 When this option is enabled, user applications can opt in to a
1438 relaxed ABI via prctl() allowing tagged addresses to be passed
1439 to system calls as pointer arguments. For details, see
799c8510 1440 Documentation/arm64/tagged-address-abi.rst.
63f0c603 1441
dd523791
WD
1442menuconfig COMPAT
1443 bool "Kernel support for 32-bit EL0"
1444 depends on ARM64_4K_PAGES || EXPERT
dd523791
WD
1445 select HAVE_UID16
1446 select OLD_SIGSUSPEND3
1447 select COMPAT_OLD_SIGACTION
1448 help
1449 This option enables support for a 32-bit EL0 running under a 64-bit
1450 kernel at EL1. AArch32-specific components such as system calls,
1451 the user helper functions, VFP support and the ptrace interface are
1452 handled appropriately by the kernel.
1453
1454 If you use a page size other than 4KB (i.e, 16KB or 64KB), please be aware
1455 that you will only be able to execute AArch32 binaries that were compiled
1456 with page size aligned segments.
1457
1458 If you want to execute 32-bit userspace applications, say Y.
1459
1460if COMPAT
1461
1462config KUSER_HELPERS
7c4791c9 1463 bool "Enable kuser helpers page for 32-bit applications"
dd523791
WD
1464 default y
1465 help
1466 Warning: disabling this option may break 32-bit user programs.
1467
1468 Provide kuser helpers to compat tasks. The kernel provides
1469 helper code to userspace in read only form at a fixed location
1470 to allow userspace to be independent of the CPU type fitted to
1471 the system. This permits binaries to be run on ARMv4 through
1472 to ARMv8 without modification.
1473
dc7a12bd 1474 See Documentation/arm/kernel_user_helpers.rst for details.
dd523791
WD
1475
1476 However, the fixed address nature of these helpers can be used
1477 by ROP (return orientated programming) authors when creating
1478 exploits.
1479
1480 If all of the binaries and libraries which run on your platform
1481 are built specifically for your platform, and make no use of
1482 these helpers, then you can turn this option off to hinder
1483 such exploits. However, in that case, if a binary or library
1484 relying on those helpers is run, it will not function correctly.
1485
1486 Say N here only if you are absolutely certain that you do not
1487 need these helpers; otherwise, the safe option is to say Y.
1488
7c4791c9
WD
1489config COMPAT_VDSO
1490 bool "Enable vDSO for 32-bit applications"
3e6f8d1f
ND
1491 depends on !CPU_BIG_ENDIAN
1492 depends on (CC_IS_CLANG && LD_IS_LLD) || "$(CROSS_COMPILE_COMPAT)" != ""
7c4791c9
WD
1493 select GENERIC_COMPAT_VDSO
1494 default y
1495 help
1496 Place in the process address space of 32-bit applications an
1497 ELF shared object providing fast implementations of gettimeofday
1498 and clock_gettime.
1499
1500 You must have a 32-bit build of glibc 2.22 or later for programs
1501 to seamlessly take advantage of this.
dd523791 1502
625412c2
ND
1503config THUMB2_COMPAT_VDSO
1504 bool "Compile the 32-bit vDSO for Thumb-2 mode" if EXPERT
1505 depends on COMPAT_VDSO
1506 default y
1507 help
1508 Compile the compat vDSO with '-mthumb -fomit-frame-pointer' if y,
1509 otherwise with '-marm'.
1510
1b907f46
WD
1511menuconfig ARMV8_DEPRECATED
1512 bool "Emulate deprecated/obsolete ARMv8 instructions"
6cfa7cc4 1513 depends on SYSCTL
1b907f46
WD
1514 help
1515 Legacy software support may require certain instructions
1516 that have been deprecated or obsoleted in the architecture.
1517
1518 Enable this config to enable selective emulation of these
1519 features.
1520
1521 If unsure, say Y
1522
1523if ARMV8_DEPRECATED
1524
1525config SWP_EMULATION
1526 bool "Emulate SWP/SWPB instructions"
1527 help
1528 ARMv8 obsoletes the use of A32 SWP/SWPB instructions such that
1529 they are always undefined. Say Y here to enable software
1530 emulation of these instructions for userspace using LDXR/STXR.
dd720784
MB
1531 This feature can be controlled at runtime with the abi.swp
1532 sysctl which is disabled by default.
1b907f46
WD
1533
1534 In some older versions of glibc [<=2.8] SWP is used during futex
1535 trylock() operations with the assumption that the code will not
1536 be preempted. This invalid assumption may be more likely to fail
1537 with SWP emulation enabled, leading to deadlock of the user
1538 application.
1539
1540 NOTE: when accessing uncached shared regions, LDXR/STXR rely
1541 on an external transaction monitoring block called a global
1542 monitor to maintain update atomicity. If your system does not
1543 implement a global monitor, this option can cause programs that
1544 perform SWP operations to uncached memory to deadlock.
1545
1546 If unsure, say Y
1547
1548config CP15_BARRIER_EMULATION
1549 bool "Emulate CP15 Barrier instructions"
1550 help
1551 The CP15 barrier instructions - CP15ISB, CP15DSB, and
1552 CP15DMB - are deprecated in ARMv8 (and ARMv7). It is
1553 strongly recommended to use the ISB, DSB, and DMB
1554 instructions instead.
1555
1556 Say Y here to enable software emulation of these
1557 instructions for AArch32 userspace code. When this option is
1558 enabled, CP15 barrier usage is traced which can help
dd720784
MB
1559 identify software that needs updating. This feature can be
1560 controlled at runtime with the abi.cp15_barrier sysctl.
1b907f46
WD
1561
1562 If unsure, say Y
1563
2d888f48
SP
1564config SETEND_EMULATION
1565 bool "Emulate SETEND instruction"
1566 help
1567 The SETEND instruction alters the data-endianness of the
1568 AArch32 EL0, and is deprecated in ARMv8.
1569
1570 Say Y here to enable software emulation of the instruction
dd720784
MB
1571 for AArch32 userspace code. This feature can be controlled
1572 at runtime with the abi.setend sysctl.
2d888f48
SP
1573
1574 Note: All the cpus on the system must have mixed endian support at EL0
1575 for this feature to be enabled. If a new CPU - which doesn't support mixed
1576 endian - is hotplugged in after this feature has been enabled, there could
1577 be unexpected results in the applications.
1578
1579 If unsure, say Y
3cb7e662 1580endif # ARMV8_DEPRECATED
1b907f46 1581
3cb7e662 1582endif # COMPAT
ba42822a 1583
0e4a0709
WD
1584menu "ARMv8.1 architectural features"
1585
1586config ARM64_HW_AFDBM
1587 bool "Support for hardware updates of the Access and Dirty page flags"
1588 default y
1589 help
1590 The ARMv8.1 architecture extensions introduce support for
1591 hardware updates of the access and dirty information in page
1592 table entries. When enabled in TCR_EL1 (HA and HD bits) on
1593 capable processors, accesses to pages with PTE_AF cleared will
1594 set this bit instead of raising an access flag fault.
1595 Similarly, writes to read-only pages with the DBM bit set will
1596 clear the read-only bit (AP[2]) instead of raising a
1597 permission fault.
1598
1599 Kernels built with this configuration option enabled continue
1600 to work on pre-ARMv8.1 hardware and the performance impact is
1601 minimal. If unsure, say Y.
1602
1603config ARM64_PAN
1604 bool "Enable support for Privileged Access Never (PAN)"
1605 default y
1606 help
3cb7e662
JH
1607 Privileged Access Never (PAN; part of the ARMv8.1 Extensions)
1608 prevents the kernel or hypervisor from accessing user-space (EL0)
1609 memory directly.
0e4a0709 1610
3cb7e662
JH
1611 Choosing this option will cause any unprotected (not using
1612 copy_to_user et al) memory access to fail with a permission fault.
0e4a0709 1613
3cb7e662
JH
1614 The feature is detected at runtime, and will remain as a 'nop'
1615 instruction if the cpu does not implement the feature.
0e4a0709 1616
364a5a8a
WD
1617config AS_HAS_LDAPR
1618 def_bool $(as-instr,.arch_extension rcpc)
1619
2decad92
CM
1620config AS_HAS_LSE_ATOMICS
1621 def_bool $(as-instr,.arch_extension lse)
1622
0e4a0709 1623config ARM64_LSE_ATOMICS
395af861
CM
1624 bool
1625 default ARM64_USE_LSE_ATOMICS
2decad92 1626 depends on AS_HAS_LSE_ATOMICS
395af861
CM
1627
1628config ARM64_USE_LSE_ATOMICS
0e4a0709 1629 bool "Atomic instructions"
b32baf91 1630 depends on JUMP_LABEL
7bd99b40 1631 default y
0e4a0709
WD
1632 help
1633 As part of the Large System Extensions, ARMv8.1 introduces new
1634 atomic instructions that are designed specifically to scale in
1635 very large systems.
1636
1637 Say Y here to make use of these instructions for the in-kernel
1638 atomic routines. This incurs a small overhead on CPUs that do
1639 not support these instructions and requires the kernel to be
7bd99b40
WD
1640 built with binutils >= 2.25 in order for the new instructions
1641 to be used.
0e4a0709 1642
3cb7e662 1643endmenu # "ARMv8.1 architectural features"
0e4a0709 1644
f993318b
WD
1645menu "ARMv8.2 architectural features"
1646
2c54b423 1647config AS_HAS_ARMV8_2
3cb7e662 1648 def_bool $(cc-option,-Wa$(comma)-march=armv8.2-a)
2c54b423
AB
1649
1650config AS_HAS_SHA3
3cb7e662 1651 def_bool $(as-instr,.arch armv8.2-a+sha3)
2c54b423 1652
d50e071f
RM
1653config ARM64_PMEM
1654 bool "Enable support for persistent memory"
1655 select ARCH_HAS_PMEM_API
5d7bdeb1 1656 select ARCH_HAS_UACCESS_FLUSHCACHE
d50e071f
RM
1657 help
1658 Say Y to enable support for the persistent memory API based on the
1659 ARMv8.2 DCPoP feature.
1660
1661 The feature is detected at runtime, and the kernel will use DC CVAC
1662 operations if DC CVAP is not supported (following the behaviour of
1663 DC CVAP itself if the system does not define a point of persistence).
1664
64c02720
XX
1665config ARM64_RAS_EXTN
1666 bool "Enable support for RAS CPU Extensions"
1667 default y
1668 help
1669 CPUs that support the Reliability, Availability and Serviceability
1670 (RAS) Extensions, part of ARMv8.2 are able to track faults and
1671 errors, classify them and report them to software.
1672
1673 On CPUs with these extensions system software can use additional
1674 barriers to determine if faults are pending and read the
1675 classification from a new set of registers.
1676
1677 Selecting this feature will allow the kernel to use these barriers
1678 and access the new registers if the system supports the extension.
1679 Platform RAS features may additionally depend on firmware support.
1680
5ffdfaed
VM
1681config ARM64_CNP
1682 bool "Enable support for Common Not Private (CNP) translations"
1683 default y
1684 depends on ARM64_PAN || !ARM64_SW_TTBR0_PAN
1685 help
1686 Common Not Private (CNP) allows translation table entries to
1687 be shared between different PEs in the same inner shareable
1688 domain, so the hardware can use this fact to optimise the
1689 caching of such entries in the TLB.
1690
1691 Selecting this option allows the CNP feature to be detected
1692 at runtime, and does not affect PEs that do not implement
1693 this feature.
1694
3cb7e662 1695endmenu # "ARMv8.2 architectural features"
f993318b 1696
04ca3204
MR
1697menu "ARMv8.3 architectural features"
1698
1699config ARM64_PTR_AUTH
1700 bool "Enable support for pointer authentication"
1701 default y
1702 help
1703 Pointer authentication (part of the ARMv8.3 Extensions) provides
1704 instructions for signing and authenticating pointers against secret
1705 keys, which can be used to mitigate Return Oriented Programming (ROP)
1706 and other attacks.
1707
1708 This option enables these instructions at EL0 (i.e. for userspace).
04ca3204
MR
1709 Choosing this option will cause the kernel to initialise secret keys
1710 for each process at exec() time, with these keys being
1711 context-switched along with the process.
1712
1713 The feature is detected at runtime. If the feature is not present in
384b40ca 1714 hardware it will not be advertised to userspace/KVM guest nor will it
dfb0589c 1715 be enabled.
04ca3204 1716
6982934e
KM
1717 If the feature is present on the boot CPU but not on a late CPU, then
1718 the late CPU will be parked. Also, if the boot CPU does not have
1719 address auth and the late CPU has then the late CPU will still boot
1720 but with the feature disabled. On such a system, this option should
1721 not be selected.
1722
b27a9f41 1723config ARM64_PTR_AUTH_KERNEL
d053e71a 1724 bool "Use pointer authentication for kernel"
b27a9f41
DK
1725 default y
1726 depends on ARM64_PTR_AUTH
1727 depends on (CC_HAS_SIGN_RETURN_ADDRESS || CC_HAS_BRANCH_PROT_PAC_RET) && AS_HAS_PAC
1728 # Modern compilers insert a .note.gnu.property section note for PAC
1729 # which is only understood by binutils starting with version 2.33.1.
1730 depends on LD_IS_LLD || LD_VERSION >= 23301 || (CC_IS_GCC && GCC_VERSION < 90100)
1731 depends on !CC_IS_CLANG || AS_HAS_CFI_NEGATE_RA_STATE
1732 depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_REGS)
1733 help
1734 If the compiler supports the -mbranch-protection or
1735 -msign-return-address flag (e.g. GCC 7 or later), then this option
1736 will cause the kernel itself to be compiled with return address
1737 protection. In this case, and if the target hardware is known to
1738 support pointer authentication, then CONFIG_STACKPROTECTOR can be
1739 disabled with minimal loss of protection.
1740
74afda40
KM
1741 This feature works with FUNCTION_GRAPH_TRACER option only if
1742 DYNAMIC_FTRACE_WITH_REGS is enabled.
1743
1744config CC_HAS_BRANCH_PROT_PAC_RET
1745 # GCC 9 or later, clang 8 or later
1746 def_bool $(cc-option,-mbranch-protection=pac-ret+leaf)
1747
1748config CC_HAS_SIGN_RETURN_ADDRESS
1749 # GCC 7, 8
1750 def_bool $(cc-option,-msign-return-address=all)
1751
1752config AS_HAS_PAC
4d0831e8 1753 def_bool $(cc-option,-Wa$(comma)-march=armv8.3-a)
74afda40 1754
3b446c7d
ND
1755config AS_HAS_CFI_NEGATE_RA_STATE
1756 def_bool $(as-instr,.cfi_startproc\n.cfi_negate_ra_state\n.cfi_endproc\n)
1757
3cb7e662 1758endmenu # "ARMv8.3 architectural features"
04ca3204 1759
2c9d45b4
IV
1760menu "ARMv8.4 architectural features"
1761
1762config ARM64_AMU_EXTN
1763 bool "Enable support for the Activity Monitors Unit CPU extension"
1764 default y
1765 help
1766 The activity monitors extension is an optional extension introduced
1767 by the ARMv8.4 CPU architecture. This enables support for version 1
1768 of the activity monitors architecture, AMUv1.
1769
1770 To enable the use of this extension on CPUs that implement it, say Y.
1771
1772 Note that for architectural reasons, firmware _must_ implement AMU
1773 support when running on CPUs that present the activity monitors
1774 extension. The required support is present in:
1775 * Version 1.5 and later of the ARM Trusted Firmware
1776
1777 For kernels that have this configuration enabled but boot with broken
1778 firmware, you may need to say N here until the firmware is fixed.
1779 Otherwise you may experience firmware panics or lockups when
1780 accessing the counter registers. Even if you are not observing these
1781 symptoms, the values returned by the register reads might not
1782 correctly reflect reality. Most commonly, the value read will be 0,
1783 indicating that the counter is not enabled.
1784
7c78f67e
ZY
1785config AS_HAS_ARMV8_4
1786 def_bool $(cc-option,-Wa$(comma)-march=armv8.4-a)
1787
1788config ARM64_TLB_RANGE
1789 bool "Enable support for tlbi range feature"
1790 default y
1791 depends on AS_HAS_ARMV8_4
1792 help
1793 ARMv8.4-TLBI provides TLBI invalidation instruction that apply to a
1794 range of input addresses.
1795
1796 The feature introduces new assembly instructions, and they were
1797 support when binutils >= 2.30.
1798
3cb7e662 1799endmenu # "ARMv8.4 architectural features"
04ca3204 1800
3e6c69a0
MB
1801menu "ARMv8.5 architectural features"
1802
f469c032
VF
1803config AS_HAS_ARMV8_5
1804 def_bool $(cc-option,-Wa$(comma)-march=armv8.5-a)
1805
383499f8
DM
1806config ARM64_BTI
1807 bool "Branch Target Identification support"
1808 default y
1809 help
1810 Branch Target Identification (part of the ARMv8.5 Extensions)
1811 provides a mechanism to limit the set of locations to which computed
1812 branch instructions such as BR or BLR can jump.
1813
1814 To make use of BTI on CPUs that support it, say Y.
1815
1816 BTI is intended to provide complementary protection to other control
1817 flow integrity protection mechanisms, such as the Pointer
1818 authentication mechanism provided as part of the ARMv8.3 Extensions.
1819 For this reason, it does not make sense to enable this option without
1820 also enabling support for pointer authentication. Thus, when
1821 enabling this option you should also select ARM64_PTR_AUTH=y.
1822
1823 Userspace binaries must also be specifically compiled to make use of
1824 this mechanism. If you say N here or the hardware does not support
1825 BTI, such binaries can still run, but you get no additional
1826 enforcement of branch destinations.
1827
97fed779
MB
1828config ARM64_BTI_KERNEL
1829 bool "Use Branch Target Identification for kernel"
1830 default y
1831 depends on ARM64_BTI
b27a9f41 1832 depends on ARM64_PTR_AUTH_KERNEL
97fed779 1833 depends on CC_HAS_BRANCH_PROT_PAC_RET_BTI
3a88d7c5
WD
1834 # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94697
1835 depends on !CC_IS_GCC || GCC_VERSION >= 100100
8cdd23c2
NC
1836 # https://github.com/llvm/llvm-project/commit/a88c722e687e6780dcd6a58718350dc76fcc4cc9
1837 depends on !CC_IS_CLANG || CLANG_VERSION >= 120000
97fed779
MB
1838 depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_REGS)
1839 help
1840 Build the kernel with Branch Target Identification annotations
1841 and enable enforcement of this for kernel code. When this option
1842 is enabled and the system supports BTI all kernel code including
1843 modular code must have BTI enabled.
1844
1845config CC_HAS_BRANCH_PROT_PAC_RET_BTI
1846 # GCC 9 or later, clang 8 or later
1847 def_bool $(cc-option,-mbranch-protection=pac-ret+leaf+bti)
1848
3e6c69a0
MB
1849config ARM64_E0PD
1850 bool "Enable support for E0PD"
1851 default y
1852 help
e717d93b
WD
1853 E0PD (part of the ARMv8.5 extensions) allows us to ensure
1854 that EL0 accesses made via TTBR1 always fault in constant time,
1855 providing similar benefits to KASLR as those provided by KPTI, but
1856 with lower overhead and without disrupting legitimate access to
1857 kernel memory such as SPE.
3e6c69a0 1858
e717d93b 1859 This option enables E0PD for TTBR1 where available.
3e6c69a0 1860
1a50ec0b
RH
1861config ARCH_RANDOM
1862 bool "Enable support for random number generation"
1863 default y
1864 help
1865 Random number generation (part of the ARMv8.5 Extensions)
1866 provides a high bandwidth, cryptographically secure
1867 hardware random number generator.
1868
89b94df9
VF
1869config ARM64_AS_HAS_MTE
1870 # Initial support for MTE went in binutils 2.32.0, checked with
1871 # ".arch armv8.5-a+memtag" below. However, this was incomplete
1872 # as a late addition to the final architecture spec (LDGM/STGM)
1873 # is only supported in the newer 2.32.x and 2.33 binutils
1874 # versions, hence the extra "stgm" instruction check below.
1875 def_bool $(as-instr,.arch armv8.5-a+memtag\nstgm xzr$(comma)[x0])
1876
1877config ARM64_MTE
1878 bool "Memory Tagging Extension support"
1879 default y
1880 depends on ARM64_AS_HAS_MTE && ARM64_TAGGED_ADDR_ABI
f469c032 1881 depends on AS_HAS_ARMV8_5
2decad92 1882 depends on AS_HAS_LSE_ATOMICS
98c970da
VF
1883 # Required for tag checking in the uaccess routines
1884 depends on ARM64_PAN
f3ba50a7 1885 select ARCH_HAS_SUBPAGE_FAULTS
89b94df9
VF
1886 select ARCH_USES_HIGH_VMA_FLAGS
1887 help
1888 Memory Tagging (part of the ARMv8.5 Extensions) provides
1889 architectural support for run-time, always-on detection of
1890 various classes of memory error to aid with software debugging
1891 to eliminate vulnerabilities arising from memory-unsafe
1892 languages.
1893
1894 This option enables the support for the Memory Tagging
1895 Extension at EL0 (i.e. for userspace).
1896
1897 Selecting this option allows the feature to be detected at
1898 runtime. Any secondary CPU not implementing this feature will
1899 not be allowed a late bring-up.
1900
1901 Userspace binaries that want to use this feature must
1902 explicitly opt in. The mechanism for the userspace is
1903 described in:
1904
1905 Documentation/arm64/memory-tagging-extension.rst.
1906
3cb7e662 1907endmenu # "ARMv8.5 architectural features"
3e6c69a0 1908
18107f8a
VM
1909menu "ARMv8.7 architectural features"
1910
1911config ARM64_EPAN
1912 bool "Enable support for Enhanced Privileged Access Never (EPAN)"
1913 default y
1914 depends on ARM64_PAN
1915 help
3cb7e662
JH
1916 Enhanced Privileged Access Never (EPAN) allows Privileged
1917 Access Never to be used with Execute-only mappings.
18107f8a 1918
3cb7e662
JH
1919 The feature is detected at runtime, and will remain disabled
1920 if the cpu does not implement the feature.
1921endmenu # "ARMv8.7 architectural features"
18107f8a 1922
ddd25ad1
DM
1923config ARM64_SVE
1924 bool "ARM Scalable Vector Extension support"
1925 default y
1926 help
1927 The Scalable Vector Extension (SVE) is an extension to the AArch64
1928 execution state which complements and extends the SIMD functionality
1929 of the base architecture to support much larger vectors and to enable
1930 additional vectorisation opportunities.
1931
1932 To enable use of this extension on CPUs that implement it, say Y.
1933
06a916fe
DM
1934 On CPUs that support the SVE2 extensions, this option will enable
1935 those too.
1936
5043694e
DM
1937 Note that for architectural reasons, firmware _must_ implement SVE
1938 support when running on SVE capable hardware. The required support
1939 is present in:
1940
1941 * version 1.5 and later of the ARM Trusted Firmware
1942 * the AArch64 boot wrapper since commit 5e1261e08abf
1943 ("bootwrapper: SVE: Enable SVE for EL2 and below").
1944
1945 For other firmware implementations, consult the firmware documentation
1946 or vendor.
1947
1948 If you need the kernel to boot on SVE-capable hardware with broken
1949 firmware, you may need to say N here until you get your firmware
1950 fixed. Otherwise, you may experience firmware panics or lockups when
1951 booting the kernel. If unsure and you are not observing these
1952 symptoms, you should assume that it is safe to say Y.
fd045f6c 1953
a1f4ccd2
MB
1954config ARM64_SME
1955 bool "ARM Scalable Matrix Extension support"
1956 default y
1957 depends on ARM64_SVE
1958 help
1959 The Scalable Matrix Extension (SME) is an extension to the AArch64
1960 execution state which utilises a substantial subset of the SVE
1961 instruction set, together with the addition of new architectural
1962 register state capable of holding two dimensional matrix tiles to
1963 enable various matrix operations.
1964
fd045f6c 1965config ARM64_MODULE_PLTS
58557e48 1966 bool "Use PLTs to allow module memory to spill over into vmalloc area"
faaa73bc 1967 depends on MODULES
fd045f6c 1968 select HAVE_MOD_ARCH_SPECIFIC
58557e48
FF
1969 help
1970 Allocate PLTs when loading modules so that jumps and calls whose
1971 targets are too far away for their relative offsets to be encoded
1972 in the instructions themselves can be bounced via veneers in the
1973 module's PLT. This allows modules to be allocated in the generic
1974 vmalloc area after the dedicated module memory area has been
1975 exhausted.
1976
1977 When running with address space randomization (KASLR), the module
1978 region itself may be too far away for ordinary relative jumps and
1979 calls, and so in that case, module PLTs are required and cannot be
1980 disabled.
1981
1982 Specific errata workaround(s) might also force module PLTs to be
1983 enabled (ARM64_ERRATUM_843419).
fd045f6c 1984
bc3c03cc
JT
1985config ARM64_PSEUDO_NMI
1986 bool "Support for NMI-like interrupts"
3c9c1dcd 1987 select ARM_GIC_V3
bc3c03cc
JT
1988 help
1989 Adds support for mimicking Non-Maskable Interrupts through the use of
1990 GIC interrupt priority. This support requires version 3 or later of
bc15cf70 1991 ARM GIC.
bc3c03cc
JT
1992
1993 This high priority configuration for interrupts needs to be
1994 explicitly enabled by setting the kernel parameter
1995 "irqchip.gicv3_pseudo_nmi" to 1.
1996
1997 If unsure, say N
1998
48ce8f80
JT
1999if ARM64_PSEUDO_NMI
2000config ARM64_DEBUG_PRIORITY_MASKING
2001 bool "Debug interrupt priority masking"
2002 help
2003 This adds runtime checks to functions enabling/disabling
2004 interrupts when using priority masking. The additional checks verify
2005 the validity of ICC_PMR_EL1 when calling concerned functions.
2006
2007 If unsure, say N
3cb7e662 2008endif # ARM64_PSEUDO_NMI
48ce8f80 2009
1e48ef7f 2010config RELOCATABLE
dd4bc607 2011 bool "Build a relocatable kernel image" if EXPERT
5cf896fb 2012 select ARCH_HAS_RELR
dd4bc607 2013 default y
1e48ef7f
AB
2014 help
2015 This builds the kernel as a Position Independent Executable (PIE),
2016 which retains all relocation metadata required to relocate the
2017 kernel binary at runtime to a different virtual address than the
2018 address it was linked at.
2019 Since AArch64 uses the RELA relocation format, this requires a
2020 relocation pass at runtime even if the kernel is loaded at the
2021 same address it was linked at.
2022
f80fb3a3
AB
2023config RANDOMIZE_BASE
2024 bool "Randomize the address of the kernel image"
b9c220b5 2025 select ARM64_MODULE_PLTS if MODULES
f80fb3a3
AB
2026 select RELOCATABLE
2027 help
2028 Randomizes the virtual address at which the kernel image is
2029 loaded, as a security feature that deters exploit attempts
2030 relying on knowledge of the location of kernel internals.
2031
2032 It is the bootloader's job to provide entropy, by passing a
2033 random u64 value in /chosen/kaslr-seed at kernel entry.
2034
2b5fe07a
AB
2035 When booting via the UEFI stub, it will invoke the firmware's
2036 EFI_RNG_PROTOCOL implementation (if available) to supply entropy
2037 to the kernel proper. In addition, it will randomise the physical
2038 location of the kernel Image as well.
2039
f80fb3a3
AB
2040 If unsure, say N.
2041
2042config RANDOMIZE_MODULE_REGION_FULL
f9c4ff2a 2043 bool "Randomize the module region over a 2 GB range"
e71a4e1b 2044 depends on RANDOMIZE_BASE
f80fb3a3
AB
2045 default y
2046 help
f9c4ff2a 2047 Randomizes the location of the module region inside a 2 GB window
f2b9ba87 2048 covering the core kernel. This way, it is less likely for modules
f80fb3a3
AB
2049 to leak information about the location of core kernel data structures
2050 but it does imply that function calls between modules and the core
2051 kernel will need to be resolved via veneers in the module PLT.
2052
2053 When this option is not set, the module region will be randomized over
2054 a limited range that contains the [_stext, _etext] interval of the
f9c4ff2a
BS
2055 core kernel, so branch relocations are almost always in range unless
2056 ARM64_MODULE_PLTS is enabled and the region is exhausted. In this
2057 particular case of region exhaustion, modules might be able to fall
2058 back to a larger 2GB area.
f80fb3a3 2059
0a1213fa
AB
2060config CC_HAVE_STACKPROTECTOR_SYSREG
2061 def_bool $(cc-option,-mstack-protector-guard=sysreg -mstack-protector-guard-reg=sp_el0 -mstack-protector-guard-offset=0)
2062
2063config STACKPROTECTOR_PER_TASK
2064 def_bool y
2065 depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_SYSREG
2066
5028fbad
HM
2067# The GPIO number here must be sorted by descending number. In case of
2068# a multiplatform kernel, we just want the highest value required by the
2069# selected platforms.
2070config ARCH_NR_GPIO
2071 int
2072 default 2048 if ARCH_APPLE
2073 default 0
2074 help
2075 Maximum number of GPIOs in the system.
2076
2077 If unsure, leave the default value.
2078
3cb7e662 2079endmenu # "Kernel Features"
8c2c3df3
CM
2080
2081menu "Boot options"
2082
5e89c55e
LP
2083config ARM64_ACPI_PARKING_PROTOCOL
2084 bool "Enable support for the ARM64 ACPI parking protocol"
2085 depends on ACPI
2086 help
2087 Enable support for the ARM64 ACPI parking protocol. If disabled
2088 the kernel will not allow booting through the ARM64 ACPI parking
2089 protocol even if the corresponding data is present in the ACPI
2090 MADT table.
2091
8c2c3df3
CM
2092config CMDLINE
2093 string "Default kernel command string"
2094 default ""
2095 help
2096 Provide a set of default command-line options at build time by
2097 entering them here. As a minimum, you should specify the the
2098 root device (e.g. root=/dev/nfs).
2099
1e40d105
TH
2100choice
2101 prompt "Kernel command line type" if CMDLINE != ""
2102 default CMDLINE_FROM_BOOTLOADER
2103 help
2104 Choose how the kernel will handle the provided default kernel
2105 command line string.
2106
2107config CMDLINE_FROM_BOOTLOADER
2108 bool "Use bootloader kernel arguments if available"
2109 help
2110 Uses the command-line options passed by the boot loader. If
2111 the boot loader doesn't provide any, the default kernel command
2112 string provided in CMDLINE will be used.
2113
8c2c3df3
CM
2114config CMDLINE_FORCE
2115 bool "Always use the default kernel command string"
2116 help
2117 Always use the default kernel command string, even if the boot
2118 loader passes other arguments to the kernel.
2119 This is useful if you cannot or don't want to change the
2120 command-line options your boot loader passes to the kernel.
2121
1e40d105
TH
2122endchoice
2123
f4f75ad5
AB
2124config EFI_STUB
2125 bool
2126
f84d0275
MS
2127config EFI
2128 bool "UEFI runtime support"
2129 depends on OF && !CPU_BIG_ENDIAN
b472db6c 2130 depends on KERNEL_MODE_NEON
2c870e61 2131 select ARCH_SUPPORTS_ACPI
f84d0275
MS
2132 select LIBFDT
2133 select UCS2_STRING
2134 select EFI_PARAMS_FROM_FDT
e15dd494 2135 select EFI_RUNTIME_WRAPPERS
f4f75ad5 2136 select EFI_STUB
2e0eb483 2137 select EFI_GENERIC_STUB
8d39cee0 2138 imply IMA_SECURE_AND_OR_TRUSTED_BOOT
f84d0275
MS
2139 default y
2140 help
2141 This option provides support for runtime services provided
2142 by UEFI firmware (such as non-volatile variables, realtime
3cb7e662 2143 clock, and platform reset). A UEFI stub is also provided to
3c7f2550
MS
2144 allow the kernel to be booted as an EFI application. This
2145 is only useful on systems that have UEFI firmware.
f84d0275 2146
d1ae8c00
YL
2147config DMI
2148 bool "Enable support for SMBIOS (DMI) tables"
2149 depends on EFI
2150 default y
2151 help
2152 This enables SMBIOS/DMI feature for systems.
2153
2154 This option is only useful on systems that have UEFI firmware.
2155 However, even with this option, the resultant kernel should
2156 continue to boot on existing non-UEFI platforms.
2157
3cb7e662 2158endmenu # "Boot options"
8c2c3df3 2159
166936ba
LP
2160menu "Power management options"
2161
2162source "kernel/power/Kconfig"
2163
82869ac5
JM
2164config ARCH_HIBERNATION_POSSIBLE
2165 def_bool y
2166 depends on CPU_PM
2167
2168config ARCH_HIBERNATION_HEADER
2169 def_bool y
2170 depends on HIBERNATION
2171
166936ba
LP
2172config ARCH_SUSPEND_POSSIBLE
2173 def_bool y
2174
3cb7e662 2175endmenu # "Power management options"
166936ba 2176
1307220d
LP
2177menu "CPU Power Management"
2178
2179source "drivers/cpuidle/Kconfig"
2180
52e7e816
RH
2181source "drivers/cpufreq/Kconfig"
2182
3cb7e662 2183endmenu # "CPU Power Management"
52e7e816 2184
b6a02173
GG
2185source "drivers/acpi/Kconfig"
2186
c3eb5b14
MZ
2187source "arch/arm64/kvm/Kconfig"
2188
2c98833a
AB
2189if CRYPTO
2190source "arch/arm64/crypto/Kconfig"
3cb7e662 2191endif # CRYPTO