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[thirdparty/kernel/stable.git] / arch / arm64 / Kconfig
1 # SPDX-License-Identifier: GPL-2.0-only
2 config ARM64
3 def_bool y
4 select ACPI_APMT if ACPI
5 select ACPI_CCA_REQUIRED if ACPI
6 select ACPI_GENERIC_GSI if ACPI
7 select ACPI_GTDT if ACPI
8 select ACPI_IORT if ACPI
9 select ACPI_REDUCED_HARDWARE_ONLY if ACPI
10 select ACPI_MCFG if (ACPI && PCI)
11 select ACPI_SPCR_TABLE if ACPI
12 select ACPI_PPTT if ACPI
13 select ARCH_HAS_DEBUG_WX
14 select ARCH_BINFMT_ELF_EXTRA_PHDRS
15 select ARCH_BINFMT_ELF_STATE
16 select ARCH_CORRECT_STACKTRACE_ON_KRETPROBE
17 select ARCH_ENABLE_HUGEPAGE_MIGRATION if HUGETLB_PAGE && MIGRATION
18 select ARCH_ENABLE_MEMORY_HOTPLUG
19 select ARCH_ENABLE_MEMORY_HOTREMOVE
20 select ARCH_ENABLE_SPLIT_PMD_PTLOCK if PGTABLE_LEVELS > 2
21 select ARCH_ENABLE_THP_MIGRATION if TRANSPARENT_HUGEPAGE
22 select ARCH_HAS_CACHE_LINE_SIZE
23 select ARCH_HAS_CURRENT_STACK_POINTER
24 select ARCH_HAS_DEBUG_VIRTUAL
25 select ARCH_HAS_DEBUG_VM_PGTABLE
26 select ARCH_HAS_DMA_PREP_COHERENT
27 select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI
28 select ARCH_HAS_FAST_MULTIPLIER
29 select ARCH_HAS_FORTIFY_SOURCE
30 select ARCH_HAS_GCOV_PROFILE_ALL
31 select ARCH_HAS_GIGANTIC_PAGE
32 select ARCH_HAS_KCOV
33 select ARCH_HAS_KEEPINITRD
34 select ARCH_HAS_MEMBARRIER_SYNC_CORE
35 select ARCH_HAS_NMI_SAFE_THIS_CPU_OPS
36 select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
37 select ARCH_HAS_PTE_DEVMAP
38 select ARCH_HAS_PTE_SPECIAL
39 select ARCH_HAS_SETUP_DMA_OPS
40 select ARCH_HAS_SET_DIRECT_MAP
41 select ARCH_HAS_SET_MEMORY
42 select ARCH_STACKWALK
43 select ARCH_HAS_STRICT_KERNEL_RWX
44 select ARCH_HAS_STRICT_MODULE_RWX
45 select ARCH_HAS_SYNC_DMA_FOR_DEVICE
46 select ARCH_HAS_SYNC_DMA_FOR_CPU
47 select ARCH_HAS_SYSCALL_WRAPPER
48 select ARCH_HAS_TEARDOWN_DMA_OPS if IOMMU_SUPPORT
49 select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
50 select ARCH_HAS_ZONE_DMA_SET if EXPERT
51 select ARCH_HAVE_ELF_PROT
52 select ARCH_HAVE_NMI_SAFE_CMPXCHG
53 select ARCH_HAVE_TRACE_MMIO_ACCESS
54 select ARCH_INLINE_READ_LOCK if !PREEMPTION
55 select ARCH_INLINE_READ_LOCK_BH if !PREEMPTION
56 select ARCH_INLINE_READ_LOCK_IRQ if !PREEMPTION
57 select ARCH_INLINE_READ_LOCK_IRQSAVE if !PREEMPTION
58 select ARCH_INLINE_READ_UNLOCK if !PREEMPTION
59 select ARCH_INLINE_READ_UNLOCK_BH if !PREEMPTION
60 select ARCH_INLINE_READ_UNLOCK_IRQ if !PREEMPTION
61 select ARCH_INLINE_READ_UNLOCK_IRQRESTORE if !PREEMPTION
62 select ARCH_INLINE_WRITE_LOCK if !PREEMPTION
63 select ARCH_INLINE_WRITE_LOCK_BH if !PREEMPTION
64 select ARCH_INLINE_WRITE_LOCK_IRQ if !PREEMPTION
65 select ARCH_INLINE_WRITE_LOCK_IRQSAVE if !PREEMPTION
66 select ARCH_INLINE_WRITE_UNLOCK if !PREEMPTION
67 select ARCH_INLINE_WRITE_UNLOCK_BH if !PREEMPTION
68 select ARCH_INLINE_WRITE_UNLOCK_IRQ if !PREEMPTION
69 select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE if !PREEMPTION
70 select ARCH_INLINE_SPIN_TRYLOCK if !PREEMPTION
71 select ARCH_INLINE_SPIN_TRYLOCK_BH if !PREEMPTION
72 select ARCH_INLINE_SPIN_LOCK if !PREEMPTION
73 select ARCH_INLINE_SPIN_LOCK_BH if !PREEMPTION
74 select ARCH_INLINE_SPIN_LOCK_IRQ if !PREEMPTION
75 select ARCH_INLINE_SPIN_LOCK_IRQSAVE if !PREEMPTION
76 select ARCH_INLINE_SPIN_UNLOCK if !PREEMPTION
77 select ARCH_INLINE_SPIN_UNLOCK_BH if !PREEMPTION
78 select ARCH_INLINE_SPIN_UNLOCK_IRQ if !PREEMPTION
79 select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE if !PREEMPTION
80 select ARCH_KEEP_MEMBLOCK
81 select ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE
82 select ARCH_USE_CMPXCHG_LOCKREF
83 select ARCH_USE_GNU_PROPERTY
84 select ARCH_USE_MEMTEST
85 select ARCH_USE_QUEUED_RWLOCKS
86 select ARCH_USE_QUEUED_SPINLOCKS
87 select ARCH_USE_SYM_ANNOTATIONS
88 select ARCH_SUPPORTS_DEBUG_PAGEALLOC
89 select ARCH_SUPPORTS_HUGETLBFS
90 select ARCH_SUPPORTS_MEMORY_FAILURE
91 select ARCH_SUPPORTS_SHADOW_CALL_STACK if CC_HAVE_SHADOW_CALL_STACK
92 select ARCH_SUPPORTS_LTO_CLANG if CPU_LITTLE_ENDIAN
93 select ARCH_SUPPORTS_LTO_CLANG_THIN
94 select ARCH_SUPPORTS_CFI_CLANG
95 select ARCH_SUPPORTS_ATOMIC_RMW
96 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
97 select ARCH_SUPPORTS_NUMA_BALANCING
98 select ARCH_SUPPORTS_PAGE_TABLE_CHECK
99 select ARCH_SUPPORTS_PER_VMA_LOCK
100 select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
101 select ARCH_WANT_COMPAT_IPC_PARSE_VERSION if COMPAT
102 select ARCH_WANT_DEFAULT_BPF_JIT
103 select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT
104 select ARCH_WANT_FRAME_POINTERS
105 select ARCH_WANT_HUGE_PMD_SHARE if ARM64_4K_PAGES || (ARM64_16K_PAGES && !ARM64_VA_BITS_36)
106 select ARCH_WANT_LD_ORPHAN_WARN
107 select ARCH_WANTS_NO_INSTR
108 select ARCH_WANTS_THP_SWAP if ARM64_4K_PAGES
109 select ARCH_HAS_UBSAN_SANITIZE_ALL
110 select ARM_AMBA
111 select ARM_ARCH_TIMER
112 select ARM_GIC
113 select AUDIT_ARCH_COMPAT_GENERIC
114 select ARM_GIC_V2M if PCI
115 select ARM_GIC_V3
116 select ARM_GIC_V3_ITS if PCI
117 select ARM_PSCI_FW
118 select BUILDTIME_TABLE_SORT
119 select CLONE_BACKWARDS
120 select COMMON_CLK
121 select CPU_PM if (SUSPEND || CPU_IDLE)
122 select CRC32
123 select DCACHE_WORD_ACCESS
124 select DYNAMIC_FTRACE if FUNCTION_TRACER
125 select DMA_BOUNCE_UNALIGNED_KMALLOC
126 select DMA_DIRECT_REMAP
127 select EDAC_SUPPORT
128 select FRAME_POINTER
129 select FUNCTION_ALIGNMENT_4B
130 select FUNCTION_ALIGNMENT_8B if DYNAMIC_FTRACE_WITH_CALL_OPS
131 select GENERIC_ALLOCATOR
132 select GENERIC_ARCH_TOPOLOGY
133 select GENERIC_CLOCKEVENTS_BROADCAST
134 select GENERIC_CPU_AUTOPROBE
135 select GENERIC_CPU_VULNERABILITIES
136 select GENERIC_EARLY_IOREMAP
137 select GENERIC_IDLE_POLL_SETUP
138 select GENERIC_IOREMAP
139 select GENERIC_IRQ_IPI
140 select GENERIC_IRQ_PROBE
141 select GENERIC_IRQ_SHOW
142 select GENERIC_IRQ_SHOW_LEVEL
143 select GENERIC_LIB_DEVMEM_IS_ALLOWED
144 select GENERIC_PCI_IOMAP
145 select GENERIC_PTDUMP
146 select GENERIC_SCHED_CLOCK
147 select GENERIC_SMP_IDLE_THREAD
148 select GENERIC_TIME_VSYSCALL
149 select GENERIC_GETTIMEOFDAY
150 select GENERIC_VDSO_TIME_NS
151 select HARDIRQS_SW_RESEND
152 select HAS_IOPORT
153 select HAVE_MOVE_PMD
154 select HAVE_MOVE_PUD
155 select HAVE_PCI
156 select HAVE_ACPI_APEI if (ACPI && EFI)
157 select HAVE_ALIGNED_STRUCT_PAGE if SLUB
158 select HAVE_ARCH_AUDITSYSCALL
159 select HAVE_ARCH_BITREVERSE
160 select HAVE_ARCH_COMPILER_H
161 select HAVE_ARCH_HUGE_VMALLOC
162 select HAVE_ARCH_HUGE_VMAP
163 select HAVE_ARCH_JUMP_LABEL
164 select HAVE_ARCH_JUMP_LABEL_RELATIVE
165 select HAVE_ARCH_KASAN if !(ARM64_16K_PAGES && ARM64_VA_BITS_48)
166 select HAVE_ARCH_KASAN_VMALLOC if HAVE_ARCH_KASAN
167 select HAVE_ARCH_KASAN_SW_TAGS if HAVE_ARCH_KASAN
168 select HAVE_ARCH_KASAN_HW_TAGS if (HAVE_ARCH_KASAN && ARM64_MTE)
169 # Some instrumentation may be unsound, hence EXPERT
170 select HAVE_ARCH_KCSAN if EXPERT
171 select HAVE_ARCH_KFENCE
172 select HAVE_ARCH_KGDB
173 select HAVE_ARCH_MMAP_RND_BITS
174 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT
175 select HAVE_ARCH_PREL32_RELOCATIONS
176 select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET
177 select HAVE_ARCH_SECCOMP_FILTER
178 select HAVE_ARCH_STACKLEAK
179 select HAVE_ARCH_THREAD_STRUCT_WHITELIST
180 select HAVE_ARCH_TRACEHOOK
181 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
182 select HAVE_ARCH_VMAP_STACK
183 select HAVE_ARM_SMCCC
184 select HAVE_ASM_MODVERSIONS
185 select HAVE_EBPF_JIT
186 select HAVE_C_RECORDMCOUNT
187 select HAVE_CMPXCHG_DOUBLE
188 select HAVE_CMPXCHG_LOCAL
189 select HAVE_CONTEXT_TRACKING_USER
190 select HAVE_DEBUG_KMEMLEAK
191 select HAVE_DMA_CONTIGUOUS
192 select HAVE_DYNAMIC_FTRACE
193 select HAVE_DYNAMIC_FTRACE_WITH_ARGS \
194 if $(cc-option,-fpatchable-function-entry=2)
195 select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS \
196 if DYNAMIC_FTRACE_WITH_ARGS && DYNAMIC_FTRACE_WITH_CALL_OPS
197 select HAVE_DYNAMIC_FTRACE_WITH_CALL_OPS \
198 if (DYNAMIC_FTRACE_WITH_ARGS && !CFI_CLANG && \
199 !CC_OPTIMIZE_FOR_SIZE)
200 select FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY \
201 if DYNAMIC_FTRACE_WITH_ARGS
202 select HAVE_SAMPLE_FTRACE_DIRECT
203 select HAVE_SAMPLE_FTRACE_DIRECT_MULTI
204 select HAVE_EFFICIENT_UNALIGNED_ACCESS
205 select HAVE_FAST_GUP
206 select HAVE_FTRACE_MCOUNT_RECORD
207 select HAVE_FUNCTION_TRACER
208 select HAVE_FUNCTION_ERROR_INJECTION
209 select HAVE_FUNCTION_GRAPH_RETVAL if HAVE_FUNCTION_GRAPH_TRACER
210 select HAVE_FUNCTION_GRAPH_TRACER
211 select HAVE_GCC_PLUGINS
212 select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && \
213 HW_PERF_EVENTS && HAVE_PERF_EVENTS_NMI
214 select HAVE_HW_BREAKPOINT if PERF_EVENTS
215 select HAVE_IOREMAP_PROT
216 select HAVE_IRQ_TIME_ACCOUNTING
217 select HAVE_KVM
218 select HAVE_MOD_ARCH_SPECIFIC
219 select HAVE_NMI
220 select HAVE_PERF_EVENTS
221 select HAVE_PERF_EVENTS_NMI if ARM64_PSEUDO_NMI
222 select HAVE_PERF_REGS
223 select HAVE_PERF_USER_STACK_DUMP
224 select HAVE_PREEMPT_DYNAMIC_KEY
225 select HAVE_REGS_AND_STACK_ACCESS_API
226 select HAVE_POSIX_CPU_TIMERS_TASK_WORK
227 select HAVE_FUNCTION_ARG_ACCESS_API
228 select MMU_GATHER_RCU_TABLE_FREE
229 select HAVE_RSEQ
230 select HAVE_STACKPROTECTOR
231 select HAVE_SYSCALL_TRACEPOINTS
232 select HAVE_KPROBES
233 select HAVE_KRETPROBES
234 select HAVE_GENERIC_VDSO
235 select HOTPLUG_CORE_SYNC_DEAD if HOTPLUG_CPU
236 select IRQ_DOMAIN
237 select IRQ_FORCED_THREADING
238 select KASAN_VMALLOC if KASAN
239 select LOCK_MM_AND_FIND_VMA
240 select MODULES_USE_ELF_RELA
241 select NEED_DMA_MAP_STATE
242 select NEED_SG_DMA_LENGTH
243 select OF
244 select OF_EARLY_FLATTREE
245 select PCI_DOMAINS_GENERIC if PCI
246 select PCI_ECAM if (ACPI && PCI)
247 select PCI_SYSCALL if PCI
248 select POWER_RESET
249 select POWER_SUPPLY
250 select SPARSE_IRQ
251 select SWIOTLB
252 select SYSCTL_EXCEPTION_TRACE
253 select THREAD_INFO_IN_TASK
254 select HAVE_ARCH_USERFAULTFD_MINOR if USERFAULTFD
255 select TRACE_IRQFLAGS_SUPPORT
256 select TRACE_IRQFLAGS_NMI_SUPPORT
257 select HAVE_SOFTIRQ_ON_OWN_STACK
258 help
259 ARM 64-bit (AArch64) Linux support.
260
261 config CLANG_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS
262 def_bool CC_IS_CLANG
263 # https://github.com/ClangBuiltLinux/linux/issues/1507
264 depends on AS_IS_GNU || (AS_IS_LLVM && (LD_IS_LLD || LD_VERSION >= 23600))
265 select HAVE_DYNAMIC_FTRACE_WITH_ARGS
266
267 config GCC_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS
268 def_bool CC_IS_GCC
269 depends on $(cc-option,-fpatchable-function-entry=2)
270 select HAVE_DYNAMIC_FTRACE_WITH_ARGS
271
272 config 64BIT
273 def_bool y
274
275 config MMU
276 def_bool y
277
278 config ARM64_PAGE_SHIFT
279 int
280 default 16 if ARM64_64K_PAGES
281 default 14 if ARM64_16K_PAGES
282 default 12
283
284 config ARM64_CONT_PTE_SHIFT
285 int
286 default 5 if ARM64_64K_PAGES
287 default 7 if ARM64_16K_PAGES
288 default 4
289
290 config ARM64_CONT_PMD_SHIFT
291 int
292 default 5 if ARM64_64K_PAGES
293 default 5 if ARM64_16K_PAGES
294 default 4
295
296 config ARCH_MMAP_RND_BITS_MIN
297 default 14 if ARM64_64K_PAGES
298 default 16 if ARM64_16K_PAGES
299 default 18
300
301 # max bits determined by the following formula:
302 # VA_BITS - PAGE_SHIFT - 3
303 config ARCH_MMAP_RND_BITS_MAX
304 default 19 if ARM64_VA_BITS=36
305 default 24 if ARM64_VA_BITS=39
306 default 27 if ARM64_VA_BITS=42
307 default 30 if ARM64_VA_BITS=47
308 default 29 if ARM64_VA_BITS=48 && ARM64_64K_PAGES
309 default 31 if ARM64_VA_BITS=48 && ARM64_16K_PAGES
310 default 33 if ARM64_VA_BITS=48
311 default 14 if ARM64_64K_PAGES
312 default 16 if ARM64_16K_PAGES
313 default 18
314
315 config ARCH_MMAP_RND_COMPAT_BITS_MIN
316 default 7 if ARM64_64K_PAGES
317 default 9 if ARM64_16K_PAGES
318 default 11
319
320 config ARCH_MMAP_RND_COMPAT_BITS_MAX
321 default 16
322
323 config NO_IOPORT_MAP
324 def_bool y if !PCI
325
326 config STACKTRACE_SUPPORT
327 def_bool y
328
329 config ILLEGAL_POINTER_VALUE
330 hex
331 default 0xdead000000000000
332
333 config LOCKDEP_SUPPORT
334 def_bool y
335
336 config GENERIC_BUG
337 def_bool y
338 depends on BUG
339
340 config GENERIC_BUG_RELATIVE_POINTERS
341 def_bool y
342 depends on GENERIC_BUG
343
344 config GENERIC_HWEIGHT
345 def_bool y
346
347 config GENERIC_CSUM
348 def_bool y
349
350 config GENERIC_CALIBRATE_DELAY
351 def_bool y
352
353 config SMP
354 def_bool y
355
356 config KERNEL_MODE_NEON
357 def_bool y
358
359 config FIX_EARLYCON_MEM
360 def_bool y
361
362 config PGTABLE_LEVELS
363 int
364 default 2 if ARM64_16K_PAGES && ARM64_VA_BITS_36
365 default 2 if ARM64_64K_PAGES && ARM64_VA_BITS_42
366 default 3 if ARM64_64K_PAGES && (ARM64_VA_BITS_48 || ARM64_VA_BITS_52)
367 default 3 if ARM64_4K_PAGES && ARM64_VA_BITS_39
368 default 3 if ARM64_16K_PAGES && ARM64_VA_BITS_47
369 default 4 if !ARM64_64K_PAGES && ARM64_VA_BITS_48
370
371 config ARCH_SUPPORTS_UPROBES
372 def_bool y
373
374 config ARCH_PROC_KCORE_TEXT
375 def_bool y
376
377 config BROKEN_GAS_INST
378 def_bool !$(as-instr,1:\n.inst 0\n.rept . - 1b\n\nnop\n.endr\n)
379
380 config BUILTIN_RETURN_ADDRESS_STRIPS_PAC
381 bool
382 # Clang's __builtin_return_adddress() strips the PAC since 12.0.0
383 # https://reviews.llvm.org/D75044
384 default y if CC_IS_CLANG && (CLANG_VERSION >= 120000)
385 # GCC's __builtin_return_address() strips the PAC since 11.1.0,
386 # and this was backported to 10.2.0, 9.4.0, 8.5.0, but not earlier
387 # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94891
388 default y if CC_IS_GCC && (GCC_VERSION >= 110100)
389 default y if CC_IS_GCC && (GCC_VERSION >= 100200) && (GCC_VERSION < 110000)
390 default y if CC_IS_GCC && (GCC_VERSION >= 90400) && (GCC_VERSION < 100000)
391 default y if CC_IS_GCC && (GCC_VERSION >= 80500) && (GCC_VERSION < 90000)
392 default n
393
394 config KASAN_SHADOW_OFFSET
395 hex
396 depends on KASAN_GENERIC || KASAN_SW_TAGS
397 default 0xdfff800000000000 if (ARM64_VA_BITS_48 || ARM64_VA_BITS_52) && !KASAN_SW_TAGS
398 default 0xdfffc00000000000 if ARM64_VA_BITS_47 && !KASAN_SW_TAGS
399 default 0xdffffe0000000000 if ARM64_VA_BITS_42 && !KASAN_SW_TAGS
400 default 0xdfffffc000000000 if ARM64_VA_BITS_39 && !KASAN_SW_TAGS
401 default 0xdffffff800000000 if ARM64_VA_BITS_36 && !KASAN_SW_TAGS
402 default 0xefff800000000000 if (ARM64_VA_BITS_48 || ARM64_VA_BITS_52) && KASAN_SW_TAGS
403 default 0xefffc00000000000 if ARM64_VA_BITS_47 && KASAN_SW_TAGS
404 default 0xeffffe0000000000 if ARM64_VA_BITS_42 && KASAN_SW_TAGS
405 default 0xefffffc000000000 if ARM64_VA_BITS_39 && KASAN_SW_TAGS
406 default 0xeffffff800000000 if ARM64_VA_BITS_36 && KASAN_SW_TAGS
407 default 0xffffffffffffffff
408
409 config UNWIND_TABLES
410 bool
411
412 source "arch/arm64/Kconfig.platforms"
413
414 menu "Kernel Features"
415
416 menu "ARM errata workarounds via the alternatives framework"
417
418 config AMPERE_ERRATUM_AC03_CPU_38
419 bool "AmpereOne: AC03_CPU_38: Certain bits in the Virtualization Translation Control Register and Translation Control Registers do not follow RES0 semantics"
420 default y
421 help
422 This option adds an alternative code sequence to work around Ampere
423 erratum AC03_CPU_38 on AmpereOne.
424
425 The affected design reports FEAT_HAFDBS as not implemented in
426 ID_AA64MMFR1_EL1.HAFDBS, but (V)TCR_ELx.{HA,HD} are not RES0
427 as required by the architecture. The unadvertised HAFDBS
428 implementation suffers from an additional erratum where hardware
429 A/D updates can occur after a PTE has been marked invalid.
430
431 The workaround forces KVM to explicitly set VTCR_EL2.HA to 0,
432 which avoids enabling unadvertised hardware Access Flag management
433 at stage-2.
434
435 If unsure, say Y.
436
437 config ARM64_WORKAROUND_CLEAN_CACHE
438 bool
439
440 config ARM64_ERRATUM_826319
441 bool "Cortex-A53: 826319: System might deadlock if a write cannot complete until read data is accepted"
442 default y
443 select ARM64_WORKAROUND_CLEAN_CACHE
444 help
445 This option adds an alternative code sequence to work around ARM
446 erratum 826319 on Cortex-A53 parts up to r0p2 with an AMBA 4 ACE or
447 AXI master interface and an L2 cache.
448
449 If a Cortex-A53 uses an AMBA AXI4 ACE interface to other processors
450 and is unable to accept a certain write via this interface, it will
451 not progress on read data presented on the read data channel and the
452 system can deadlock.
453
454 The workaround promotes data cache clean instructions to
455 data cache clean-and-invalidate.
456 Please note that this does not necessarily enable the workaround,
457 as it depends on the alternative framework, which will only patch
458 the kernel if an affected CPU is detected.
459
460 If unsure, say Y.
461
462 config ARM64_ERRATUM_827319
463 bool "Cortex-A53: 827319: Data cache clean instructions might cause overlapping transactions to the interconnect"
464 default y
465 select ARM64_WORKAROUND_CLEAN_CACHE
466 help
467 This option adds an alternative code sequence to work around ARM
468 erratum 827319 on Cortex-A53 parts up to r0p2 with an AMBA 5 CHI
469 master interface and an L2 cache.
470
471 Under certain conditions this erratum can cause a clean line eviction
472 to occur at the same time as another transaction to the same address
473 on the AMBA 5 CHI interface, which can cause data corruption if the
474 interconnect reorders the two transactions.
475
476 The workaround promotes data cache clean instructions to
477 data cache clean-and-invalidate.
478 Please note that this does not necessarily enable the workaround,
479 as it depends on the alternative framework, which will only patch
480 the kernel if an affected CPU is detected.
481
482 If unsure, say Y.
483
484 config ARM64_ERRATUM_824069
485 bool "Cortex-A53: 824069: Cache line might not be marked as clean after a CleanShared snoop"
486 default y
487 select ARM64_WORKAROUND_CLEAN_CACHE
488 help
489 This option adds an alternative code sequence to work around ARM
490 erratum 824069 on Cortex-A53 parts up to r0p2 when it is connected
491 to a coherent interconnect.
492
493 If a Cortex-A53 processor is executing a store or prefetch for
494 write instruction at the same time as a processor in another
495 cluster is executing a cache maintenance operation to the same
496 address, then this erratum might cause a clean cache line to be
497 incorrectly marked as dirty.
498
499 The workaround promotes data cache clean instructions to
500 data cache clean-and-invalidate.
501 Please note that this option does not necessarily enable the
502 workaround, as it depends on the alternative framework, which will
503 only patch the kernel if an affected CPU is detected.
504
505 If unsure, say Y.
506
507 config ARM64_ERRATUM_819472
508 bool "Cortex-A53: 819472: Store exclusive instructions might cause data corruption"
509 default y
510 select ARM64_WORKAROUND_CLEAN_CACHE
511 help
512 This option adds an alternative code sequence to work around ARM
513 erratum 819472 on Cortex-A53 parts up to r0p1 with an L2 cache
514 present when it is connected to a coherent interconnect.
515
516 If the processor is executing a load and store exclusive sequence at
517 the same time as a processor in another cluster is executing a cache
518 maintenance operation to the same address, then this erratum might
519 cause data corruption.
520
521 The workaround promotes data cache clean instructions to
522 data cache clean-and-invalidate.
523 Please note that this does not necessarily enable the workaround,
524 as it depends on the alternative framework, which will only patch
525 the kernel if an affected CPU is detected.
526
527 If unsure, say Y.
528
529 config ARM64_ERRATUM_832075
530 bool "Cortex-A57: 832075: possible deadlock on mixing exclusive memory accesses with device loads"
531 default y
532 help
533 This option adds an alternative code sequence to work around ARM
534 erratum 832075 on Cortex-A57 parts up to r1p2.
535
536 Affected Cortex-A57 parts might deadlock when exclusive load/store
537 instructions to Write-Back memory are mixed with Device loads.
538
539 The workaround is to promote device loads to use Load-Acquire
540 semantics.
541 Please note that this does not necessarily enable the workaround,
542 as it depends on the alternative framework, which will only patch
543 the kernel if an affected CPU is detected.
544
545 If unsure, say Y.
546
547 config ARM64_ERRATUM_834220
548 bool "Cortex-A57: 834220: Stage 2 translation fault might be incorrectly reported in presence of a Stage 1 fault"
549 depends on KVM
550 default y
551 help
552 This option adds an alternative code sequence to work around ARM
553 erratum 834220 on Cortex-A57 parts up to r1p2.
554
555 Affected Cortex-A57 parts might report a Stage 2 translation
556 fault as the result of a Stage 1 fault for load crossing a
557 page boundary when there is a permission or device memory
558 alignment fault at Stage 1 and a translation fault at Stage 2.
559
560 The workaround is to verify that the Stage 1 translation
561 doesn't generate a fault before handling the Stage 2 fault.
562 Please note that this does not necessarily enable the workaround,
563 as it depends on the alternative framework, which will only patch
564 the kernel if an affected CPU is detected.
565
566 If unsure, say Y.
567
568 config ARM64_ERRATUM_1742098
569 bool "Cortex-A57/A72: 1742098: ELR recorded incorrectly on interrupt taken between cryptographic instructions in a sequence"
570 depends on COMPAT
571 default y
572 help
573 This option removes the AES hwcap for aarch32 user-space to
574 workaround erratum 1742098 on Cortex-A57 and Cortex-A72.
575
576 Affected parts may corrupt the AES state if an interrupt is
577 taken between a pair of AES instructions. These instructions
578 are only present if the cryptography extensions are present.
579 All software should have a fallback implementation for CPUs
580 that don't implement the cryptography extensions.
581
582 If unsure, say Y.
583
584 config ARM64_ERRATUM_845719
585 bool "Cortex-A53: 845719: a load might read incorrect data"
586 depends on COMPAT
587 default y
588 help
589 This option adds an alternative code sequence to work around ARM
590 erratum 845719 on Cortex-A53 parts up to r0p4.
591
592 When running a compat (AArch32) userspace on an affected Cortex-A53
593 part, a load at EL0 from a virtual address that matches the bottom 32
594 bits of the virtual address used by a recent load at (AArch64) EL1
595 might return incorrect data.
596
597 The workaround is to write the contextidr_el1 register on exception
598 return to a 32-bit task.
599 Please note that this does not necessarily enable the workaround,
600 as it depends on the alternative framework, which will only patch
601 the kernel if an affected CPU is detected.
602
603 If unsure, say Y.
604
605 config ARM64_ERRATUM_843419
606 bool "Cortex-A53: 843419: A load or store might access an incorrect address"
607 default y
608 help
609 This option links the kernel with '--fix-cortex-a53-843419' and
610 enables PLT support to replace certain ADRP instructions, which can
611 cause subsequent memory accesses to use an incorrect address on
612 Cortex-A53 parts up to r0p4.
613
614 If unsure, say Y.
615
616 config ARM64_LD_HAS_FIX_ERRATUM_843419
617 def_bool $(ld-option,--fix-cortex-a53-843419)
618
619 config ARM64_ERRATUM_1024718
620 bool "Cortex-A55: 1024718: Update of DBM/AP bits without break before make might result in incorrect update"
621 default y
622 help
623 This option adds a workaround for ARM Cortex-A55 Erratum 1024718.
624
625 Affected Cortex-A55 cores (all revisions) could cause incorrect
626 update of the hardware dirty bit when the DBM/AP bits are updated
627 without a break-before-make. The workaround is to disable the usage
628 of hardware DBM locally on the affected cores. CPUs not affected by
629 this erratum will continue to use the feature.
630
631 If unsure, say Y.
632
633 config ARM64_ERRATUM_1418040
634 bool "Cortex-A76/Neoverse-N1: MRC read following MRRC read of specific Generic Timer in AArch32 might give incorrect result"
635 default y
636 depends on COMPAT
637 help
638 This option adds a workaround for ARM Cortex-A76/Neoverse-N1
639 errata 1188873 and 1418040.
640
641 Affected Cortex-A76/Neoverse-N1 cores (r0p0 to r3p1) could
642 cause register corruption when accessing the timer registers
643 from AArch32 userspace.
644
645 If unsure, say Y.
646
647 config ARM64_WORKAROUND_SPECULATIVE_AT
648 bool
649
650 config ARM64_ERRATUM_1165522
651 bool "Cortex-A76: 1165522: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
652 default y
653 select ARM64_WORKAROUND_SPECULATIVE_AT
654 help
655 This option adds a workaround for ARM Cortex-A76 erratum 1165522.
656
657 Affected Cortex-A76 cores (r0p0, r1p0, r2p0) could end-up with
658 corrupted TLBs by speculating an AT instruction during a guest
659 context switch.
660
661 If unsure, say Y.
662
663 config ARM64_ERRATUM_1319367
664 bool "Cortex-A57/A72: 1319537: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
665 default y
666 select ARM64_WORKAROUND_SPECULATIVE_AT
667 help
668 This option adds work arounds for ARM Cortex-A57 erratum 1319537
669 and A72 erratum 1319367
670
671 Cortex-A57 and A72 cores could end-up with corrupted TLBs by
672 speculating an AT instruction during a guest context switch.
673
674 If unsure, say Y.
675
676 config ARM64_ERRATUM_1530923
677 bool "Cortex-A55: 1530923: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
678 default y
679 select ARM64_WORKAROUND_SPECULATIVE_AT
680 help
681 This option adds a workaround for ARM Cortex-A55 erratum 1530923.
682
683 Affected Cortex-A55 cores (r0p0, r0p1, r1p0, r2p0) could end-up with
684 corrupted TLBs by speculating an AT instruction during a guest
685 context switch.
686
687 If unsure, say Y.
688
689 config ARM64_WORKAROUND_REPEAT_TLBI
690 bool
691
692 config ARM64_ERRATUM_2441007
693 bool "Cortex-A55: Completion of affected memory accesses might not be guaranteed by completion of a TLBI"
694 default y
695 select ARM64_WORKAROUND_REPEAT_TLBI
696 help
697 This option adds a workaround for ARM Cortex-A55 erratum #2441007.
698
699 Under very rare circumstances, affected Cortex-A55 CPUs
700 may not handle a race between a break-before-make sequence on one
701 CPU, and another CPU accessing the same page. This could allow a
702 store to a page that has been unmapped.
703
704 Work around this by adding the affected CPUs to the list that needs
705 TLB sequences to be done twice.
706
707 If unsure, say Y.
708
709 config ARM64_ERRATUM_1286807
710 bool "Cortex-A76: Modification of the translation table for a virtual address might lead to read-after-read ordering violation"
711 default y
712 select ARM64_WORKAROUND_REPEAT_TLBI
713 help
714 This option adds a workaround for ARM Cortex-A76 erratum 1286807.
715
716 On the affected Cortex-A76 cores (r0p0 to r3p0), if a virtual
717 address for a cacheable mapping of a location is being
718 accessed by a core while another core is remapping the virtual
719 address to a new physical page using the recommended
720 break-before-make sequence, then under very rare circumstances
721 TLBI+DSB completes before a read using the translation being
722 invalidated has been observed by other observers. The
723 workaround repeats the TLBI+DSB operation.
724
725 config ARM64_ERRATUM_1463225
726 bool "Cortex-A76: Software Step might prevent interrupt recognition"
727 default y
728 help
729 This option adds a workaround for Arm Cortex-A76 erratum 1463225.
730
731 On the affected Cortex-A76 cores (r0p0 to r3p1), software stepping
732 of a system call instruction (SVC) can prevent recognition of
733 subsequent interrupts when software stepping is disabled in the
734 exception handler of the system call and either kernel debugging
735 is enabled or VHE is in use.
736
737 Work around the erratum by triggering a dummy step exception
738 when handling a system call from a task that is being stepped
739 in a VHE configuration of the kernel.
740
741 If unsure, say Y.
742
743 config ARM64_ERRATUM_1542419
744 bool "Neoverse-N1: workaround mis-ordering of instruction fetches"
745 default y
746 help
747 This option adds a workaround for ARM Neoverse-N1 erratum
748 1542419.
749
750 Affected Neoverse-N1 cores could execute a stale instruction when
751 modified by another CPU. The workaround depends on a firmware
752 counterpart.
753
754 Workaround the issue by hiding the DIC feature from EL0. This
755 forces user-space to perform cache maintenance.
756
757 If unsure, say Y.
758
759 config ARM64_ERRATUM_1508412
760 bool "Cortex-A77: 1508412: workaround deadlock on sequence of NC/Device load and store exclusive or PAR read"
761 default y
762 help
763 This option adds a workaround for Arm Cortex-A77 erratum 1508412.
764
765 Affected Cortex-A77 cores (r0p0, r1p0) could deadlock on a sequence
766 of a store-exclusive or read of PAR_EL1 and a load with device or
767 non-cacheable memory attributes. The workaround depends on a firmware
768 counterpart.
769
770 KVM guests must also have the workaround implemented or they can
771 deadlock the system.
772
773 Work around the issue by inserting DMB SY barriers around PAR_EL1
774 register reads and warning KVM users. The DMB barrier is sufficient
775 to prevent a speculative PAR_EL1 read.
776
777 If unsure, say Y.
778
779 config ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
780 bool
781
782 config ARM64_ERRATUM_2051678
783 bool "Cortex-A510: 2051678: disable Hardware Update of the page table dirty bit"
784 default y
785 help
786 This options adds the workaround for ARM Cortex-A510 erratum ARM64_ERRATUM_2051678.
787 Affected Cortex-A510 might not respect the ordering rules for
788 hardware update of the page table's dirty bit. The workaround
789 is to not enable the feature on affected CPUs.
790
791 If unsure, say Y.
792
793 config ARM64_ERRATUM_2077057
794 bool "Cortex-A510: 2077057: workaround software-step corrupting SPSR_EL2"
795 default y
796 help
797 This option adds the workaround for ARM Cortex-A510 erratum 2077057.
798 Affected Cortex-A510 may corrupt SPSR_EL2 when the a step exception is
799 expected, but a Pointer Authentication trap is taken instead. The
800 erratum causes SPSR_EL1 to be copied to SPSR_EL2, which could allow
801 EL1 to cause a return to EL2 with a guest controlled ELR_EL2.
802
803 This can only happen when EL2 is stepping EL1.
804
805 When these conditions occur, the SPSR_EL2 value is unchanged from the
806 previous guest entry, and can be restored from the in-memory copy.
807
808 If unsure, say Y.
809
810 config ARM64_ERRATUM_2658417
811 bool "Cortex-A510: 2658417: remove BF16 support due to incorrect result"
812 default y
813 help
814 This option adds the workaround for ARM Cortex-A510 erratum 2658417.
815 Affected Cortex-A510 (r0p0 to r1p1) may produce the wrong result for
816 BFMMLA or VMMLA instructions in rare circumstances when a pair of
817 A510 CPUs are using shared neon hardware. As the sharing is not
818 discoverable by the kernel, hide the BF16 HWCAP to indicate that
819 user-space should not be using these instructions.
820
821 If unsure, say Y.
822
823 config ARM64_ERRATUM_2119858
824 bool "Cortex-A710/X2: 2119858: workaround TRBE overwriting trace data in FILL mode"
825 default y
826 depends on CORESIGHT_TRBE
827 select ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
828 help
829 This option adds the workaround for ARM Cortex-A710/X2 erratum 2119858.
830
831 Affected Cortex-A710/X2 cores could overwrite up to 3 cache lines of trace
832 data at the base of the buffer (pointed to by TRBASER_EL1) in FILL mode in
833 the event of a WRAP event.
834
835 Work around the issue by always making sure we move the TRBPTR_EL1 by
836 256 bytes before enabling the buffer and filling the first 256 bytes of
837 the buffer with ETM ignore packets upon disabling.
838
839 If unsure, say Y.
840
841 config ARM64_ERRATUM_2139208
842 bool "Neoverse-N2: 2139208: workaround TRBE overwriting trace data in FILL mode"
843 default y
844 depends on CORESIGHT_TRBE
845 select ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
846 help
847 This option adds the workaround for ARM Neoverse-N2 erratum 2139208.
848
849 Affected Neoverse-N2 cores could overwrite up to 3 cache lines of trace
850 data at the base of the buffer (pointed to by TRBASER_EL1) in FILL mode in
851 the event of a WRAP event.
852
853 Work around the issue by always making sure we move the TRBPTR_EL1 by
854 256 bytes before enabling the buffer and filling the first 256 bytes of
855 the buffer with ETM ignore packets upon disabling.
856
857 If unsure, say Y.
858
859 config ARM64_WORKAROUND_TSB_FLUSH_FAILURE
860 bool
861
862 config ARM64_ERRATUM_2054223
863 bool "Cortex-A710: 2054223: workaround TSB instruction failing to flush trace"
864 default y
865 select ARM64_WORKAROUND_TSB_FLUSH_FAILURE
866 help
867 Enable workaround for ARM Cortex-A710 erratum 2054223
868
869 Affected cores may fail to flush the trace data on a TSB instruction, when
870 the PE is in trace prohibited state. This will cause losing a few bytes
871 of the trace cached.
872
873 Workaround is to issue two TSB consecutively on affected cores.
874
875 If unsure, say Y.
876
877 config ARM64_ERRATUM_2067961
878 bool "Neoverse-N2: 2067961: workaround TSB instruction failing to flush trace"
879 default y
880 select ARM64_WORKAROUND_TSB_FLUSH_FAILURE
881 help
882 Enable workaround for ARM Neoverse-N2 erratum 2067961
883
884 Affected cores may fail to flush the trace data on a TSB instruction, when
885 the PE is in trace prohibited state. This will cause losing a few bytes
886 of the trace cached.
887
888 Workaround is to issue two TSB consecutively on affected cores.
889
890 If unsure, say Y.
891
892 config ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE
893 bool
894
895 config ARM64_ERRATUM_2253138
896 bool "Neoverse-N2: 2253138: workaround TRBE writing to address out-of-range"
897 depends on CORESIGHT_TRBE
898 default y
899 select ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE
900 help
901 This option adds the workaround for ARM Neoverse-N2 erratum 2253138.
902
903 Affected Neoverse-N2 cores might write to an out-of-range address, not reserved
904 for TRBE. Under some conditions, the TRBE might generate a write to the next
905 virtually addressed page following the last page of the TRBE address space
906 (i.e., the TRBLIMITR_EL1.LIMIT), instead of wrapping around to the base.
907
908 Work around this in the driver by always making sure that there is a
909 page beyond the TRBLIMITR_EL1.LIMIT, within the space allowed for the TRBE.
910
911 If unsure, say Y.
912
913 config ARM64_ERRATUM_2224489
914 bool "Cortex-A710/X2: 2224489: workaround TRBE writing to address out-of-range"
915 depends on CORESIGHT_TRBE
916 default y
917 select ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE
918 help
919 This option adds the workaround for ARM Cortex-A710/X2 erratum 2224489.
920
921 Affected Cortex-A710/X2 cores might write to an out-of-range address, not reserved
922 for TRBE. Under some conditions, the TRBE might generate a write to the next
923 virtually addressed page following the last page of the TRBE address space
924 (i.e., the TRBLIMITR_EL1.LIMIT), instead of wrapping around to the base.
925
926 Work around this in the driver by always making sure that there is a
927 page beyond the TRBLIMITR_EL1.LIMIT, within the space allowed for the TRBE.
928
929 If unsure, say Y.
930
931 config ARM64_ERRATUM_2441009
932 bool "Cortex-A510: Completion of affected memory accesses might not be guaranteed by completion of a TLBI"
933 default y
934 select ARM64_WORKAROUND_REPEAT_TLBI
935 help
936 This option adds a workaround for ARM Cortex-A510 erratum #2441009.
937
938 Under very rare circumstances, affected Cortex-A510 CPUs
939 may not handle a race between a break-before-make sequence on one
940 CPU, and another CPU accessing the same page. This could allow a
941 store to a page that has been unmapped.
942
943 Work around this by adding the affected CPUs to the list that needs
944 TLB sequences to be done twice.
945
946 If unsure, say Y.
947
948 config ARM64_ERRATUM_2064142
949 bool "Cortex-A510: 2064142: workaround TRBE register writes while disabled"
950 depends on CORESIGHT_TRBE
951 default y
952 help
953 This option adds the workaround for ARM Cortex-A510 erratum 2064142.
954
955 Affected Cortex-A510 core might fail to write into system registers after the
956 TRBE has been disabled. Under some conditions after the TRBE has been disabled
957 writes into TRBE registers TRBLIMITR_EL1, TRBPTR_EL1, TRBBASER_EL1, TRBSR_EL1,
958 and TRBTRG_EL1 will be ignored and will not be effected.
959
960 Work around this in the driver by executing TSB CSYNC and DSB after collection
961 is stopped and before performing a system register write to one of the affected
962 registers.
963
964 If unsure, say Y.
965
966 config ARM64_ERRATUM_2038923
967 bool "Cortex-A510: 2038923: workaround TRBE corruption with enable"
968 depends on CORESIGHT_TRBE
969 default y
970 help
971 This option adds the workaround for ARM Cortex-A510 erratum 2038923.
972
973 Affected Cortex-A510 core might cause an inconsistent view on whether trace is
974 prohibited within the CPU. As a result, the trace buffer or trace buffer state
975 might be corrupted. This happens after TRBE buffer has been enabled by setting
976 TRBLIMITR_EL1.E, followed by just a single context synchronization event before
977 execution changes from a context, in which trace is prohibited to one where it
978 isn't, or vice versa. In these mentioned conditions, the view of whether trace
979 is prohibited is inconsistent between parts of the CPU, and the trace buffer or
980 the trace buffer state might be corrupted.
981
982 Work around this in the driver by preventing an inconsistent view of whether the
983 trace is prohibited or not based on TRBLIMITR_EL1.E by immediately following a
984 change to TRBLIMITR_EL1.E with at least one ISB instruction before an ERET, or
985 two ISB instructions if no ERET is to take place.
986
987 If unsure, say Y.
988
989 config ARM64_ERRATUM_1902691
990 bool "Cortex-A510: 1902691: workaround TRBE trace corruption"
991 depends on CORESIGHT_TRBE
992 default y
993 help
994 This option adds the workaround for ARM Cortex-A510 erratum 1902691.
995
996 Affected Cortex-A510 core might cause trace data corruption, when being written
997 into the memory. Effectively TRBE is broken and hence cannot be used to capture
998 trace data.
999
1000 Work around this problem in the driver by just preventing TRBE initialization on
1001 affected cpus. The firmware must have disabled the access to TRBE for the kernel
1002 on such implementations. This will cover the kernel for any firmware that doesn't
1003 do this already.
1004
1005 If unsure, say Y.
1006
1007 config ARM64_ERRATUM_2457168
1008 bool "Cortex-A510: 2457168: workaround for AMEVCNTR01 incrementing incorrectly"
1009 depends on ARM64_AMU_EXTN
1010 default y
1011 help
1012 This option adds the workaround for ARM Cortex-A510 erratum 2457168.
1013
1014 The AMU counter AMEVCNTR01 (constant counter) should increment at the same rate
1015 as the system counter. On affected Cortex-A510 cores AMEVCNTR01 increments
1016 incorrectly giving a significantly higher output value.
1017
1018 Work around this problem by returning 0 when reading the affected counter in
1019 key locations that results in disabling all users of this counter. This effect
1020 is the same to firmware disabling affected counters.
1021
1022 If unsure, say Y.
1023
1024 config ARM64_ERRATUM_2645198
1025 bool "Cortex-A715: 2645198: Workaround possible [ESR|FAR]_ELx corruption"
1026 default y
1027 help
1028 This option adds the workaround for ARM Cortex-A715 erratum 2645198.
1029
1030 If a Cortex-A715 cpu sees a page mapping permissions change from executable
1031 to non-executable, it may corrupt the ESR_ELx and FAR_ELx registers on the
1032 next instruction abort caused by permission fault.
1033
1034 Only user-space does executable to non-executable permission transition via
1035 mprotect() system call. Workaround the problem by doing a break-before-make
1036 TLB invalidation, for all changes to executable user space mappings.
1037
1038 If unsure, say Y.
1039
1040 config ARM64_ERRATUM_2966298
1041 bool "Cortex-A520: 2966298: workaround for speculatively executed unprivileged load"
1042 default y
1043 help
1044 This option adds the workaround for ARM Cortex-A520 erratum 2966298.
1045
1046 On an affected Cortex-A520 core, a speculatively executed unprivileged
1047 load might leak data from a privileged level via a cache side channel.
1048
1049 Work around this problem by executing a TLBI before returning to EL0.
1050
1051 If unsure, say Y.
1052
1053 config CAVIUM_ERRATUM_22375
1054 bool "Cavium erratum 22375, 24313"
1055 default y
1056 help
1057 Enable workaround for errata 22375 and 24313.
1058
1059 This implements two gicv3-its errata workarounds for ThunderX. Both
1060 with a small impact affecting only ITS table allocation.
1061
1062 erratum 22375: only alloc 8MB table size
1063 erratum 24313: ignore memory access type
1064
1065 The fixes are in ITS initialization and basically ignore memory access
1066 type and table size provided by the TYPER and BASER registers.
1067
1068 If unsure, say Y.
1069
1070 config CAVIUM_ERRATUM_23144
1071 bool "Cavium erratum 23144: ITS SYNC hang on dual socket system"
1072 depends on NUMA
1073 default y
1074 help
1075 ITS SYNC command hang for cross node io and collections/cpu mapping.
1076
1077 If unsure, say Y.
1078
1079 config CAVIUM_ERRATUM_23154
1080 bool "Cavium errata 23154 and 38545: GICv3 lacks HW synchronisation"
1081 default y
1082 help
1083 The ThunderX GICv3 implementation requires a modified version for
1084 reading the IAR status to ensure data synchronization
1085 (access to icc_iar1_el1 is not sync'ed before and after).
1086
1087 It also suffers from erratum 38545 (also present on Marvell's
1088 OcteonTX and OcteonTX2), resulting in deactivated interrupts being
1089 spuriously presented to the CPU interface.
1090
1091 If unsure, say Y.
1092
1093 config CAVIUM_ERRATUM_27456
1094 bool "Cavium erratum 27456: Broadcast TLBI instructions may cause icache corruption"
1095 default y
1096 help
1097 On ThunderX T88 pass 1.x through 2.1 parts, broadcast TLBI
1098 instructions may cause the icache to become corrupted if it
1099 contains data for a non-current ASID. The fix is to
1100 invalidate the icache when changing the mm context.
1101
1102 If unsure, say Y.
1103
1104 config CAVIUM_ERRATUM_30115
1105 bool "Cavium erratum 30115: Guest may disable interrupts in host"
1106 default y
1107 help
1108 On ThunderX T88 pass 1.x through 2.2, T81 pass 1.0 through
1109 1.2, and T83 Pass 1.0, KVM guest execution may disable
1110 interrupts in host. Trapping both GICv3 group-0 and group-1
1111 accesses sidesteps the issue.
1112
1113 If unsure, say Y.
1114
1115 config CAVIUM_TX2_ERRATUM_219
1116 bool "Cavium ThunderX2 erratum 219: PRFM between TTBR change and ISB fails"
1117 default y
1118 help
1119 On Cavium ThunderX2, a load, store or prefetch instruction between a
1120 TTBR update and the corresponding context synchronizing operation can
1121 cause a spurious Data Abort to be delivered to any hardware thread in
1122 the CPU core.
1123
1124 Work around the issue by avoiding the problematic code sequence and
1125 trapping KVM guest TTBRx_EL1 writes to EL2 when SMT is enabled. The
1126 trap handler performs the corresponding register access, skips the
1127 instruction and ensures context synchronization by virtue of the
1128 exception return.
1129
1130 If unsure, say Y.
1131
1132 config FUJITSU_ERRATUM_010001
1133 bool "Fujitsu-A64FX erratum E#010001: Undefined fault may occur wrongly"
1134 default y
1135 help
1136 This option adds a workaround for Fujitsu-A64FX erratum E#010001.
1137 On some variants of the Fujitsu-A64FX cores ver(1.0, 1.1), memory
1138 accesses may cause undefined fault (Data abort, DFSC=0b111111).
1139 This fault occurs under a specific hardware condition when a
1140 load/store instruction performs an address translation using:
1141 case-1 TTBR0_EL1 with TCR_EL1.NFD0 == 1.
1142 case-2 TTBR0_EL2 with TCR_EL2.NFD0 == 1.
1143 case-3 TTBR1_EL1 with TCR_EL1.NFD1 == 1.
1144 case-4 TTBR1_EL2 with TCR_EL2.NFD1 == 1.
1145
1146 The workaround is to ensure these bits are clear in TCR_ELx.
1147 The workaround only affects the Fujitsu-A64FX.
1148
1149 If unsure, say Y.
1150
1151 config HISILICON_ERRATUM_161600802
1152 bool "Hip07 161600802: Erroneous redistributor VLPI base"
1153 default y
1154 help
1155 The HiSilicon Hip07 SoC uses the wrong redistributor base
1156 when issued ITS commands such as VMOVP and VMAPP, and requires
1157 a 128kB offset to be applied to the target address in this commands.
1158
1159 If unsure, say Y.
1160
1161 config QCOM_FALKOR_ERRATUM_1003
1162 bool "Falkor E1003: Incorrect translation due to ASID change"
1163 default y
1164 help
1165 On Falkor v1, an incorrect ASID may be cached in the TLB when ASID
1166 and BADDR are changed together in TTBRx_EL1. Since we keep the ASID
1167 in TTBR1_EL1, this situation only occurs in the entry trampoline and
1168 then only for entries in the walk cache, since the leaf translation
1169 is unchanged. Work around the erratum by invalidating the walk cache
1170 entries for the trampoline before entering the kernel proper.
1171
1172 config QCOM_FALKOR_ERRATUM_1009
1173 bool "Falkor E1009: Prematurely complete a DSB after a TLBI"
1174 default y
1175 select ARM64_WORKAROUND_REPEAT_TLBI
1176 help
1177 On Falkor v1, the CPU may prematurely complete a DSB following a
1178 TLBI xxIS invalidate maintenance operation. Repeat the TLBI operation
1179 one more time to fix the issue.
1180
1181 If unsure, say Y.
1182
1183 config QCOM_QDF2400_ERRATUM_0065
1184 bool "QDF2400 E0065: Incorrect GITS_TYPER.ITT_Entry_size"
1185 default y
1186 help
1187 On Qualcomm Datacenter Technologies QDF2400 SoC, ITS hardware reports
1188 ITE size incorrectly. The GITS_TYPER.ITT_Entry_size field should have
1189 been indicated as 16Bytes (0xf), not 8Bytes (0x7).
1190
1191 If unsure, say Y.
1192
1193 config QCOM_FALKOR_ERRATUM_E1041
1194 bool "Falkor E1041: Speculative instruction fetches might cause errant memory access"
1195 default y
1196 help
1197 Falkor CPU may speculatively fetch instructions from an improper
1198 memory location when MMU translation is changed from SCTLR_ELn[M]=1
1199 to SCTLR_ELn[M]=0. Prefix an ISB instruction to fix the problem.
1200
1201 If unsure, say Y.
1202
1203 config NVIDIA_CARMEL_CNP_ERRATUM
1204 bool "NVIDIA Carmel CNP: CNP on Carmel semantically different than ARM cores"
1205 default y
1206 help
1207 If CNP is enabled on Carmel cores, non-sharable TLBIs on a core will not
1208 invalidate shared TLB entries installed by a different core, as it would
1209 on standard ARM cores.
1210
1211 If unsure, say Y.
1212
1213 config ROCKCHIP_ERRATUM_3588001
1214 bool "Rockchip 3588001: GIC600 can not support shareability attributes"
1215 default y
1216 help
1217 The Rockchip RK3588 GIC600 SoC integration does not support ACE/ACE-lite.
1218 This means, that its sharability feature may not be used, even though it
1219 is supported by the IP itself.
1220
1221 If unsure, say Y.
1222
1223 config SOCIONEXT_SYNQUACER_PREITS
1224 bool "Socionext Synquacer: Workaround for GICv3 pre-ITS"
1225 default y
1226 help
1227 Socionext Synquacer SoCs implement a separate h/w block to generate
1228 MSI doorbell writes with non-zero values for the device ID.
1229
1230 If unsure, say Y.
1231
1232 endmenu # "ARM errata workarounds via the alternatives framework"
1233
1234 choice
1235 prompt "Page size"
1236 default ARM64_4K_PAGES
1237 help
1238 Page size (translation granule) configuration.
1239
1240 config ARM64_4K_PAGES
1241 bool "4KB"
1242 help
1243 This feature enables 4KB pages support.
1244
1245 config ARM64_16K_PAGES
1246 bool "16KB"
1247 help
1248 The system will use 16KB pages support. AArch32 emulation
1249 requires applications compiled with 16K (or a multiple of 16K)
1250 aligned segments.
1251
1252 config ARM64_64K_PAGES
1253 bool "64KB"
1254 help
1255 This feature enables 64KB pages support (4KB by default)
1256 allowing only two levels of page tables and faster TLB
1257 look-up. AArch32 emulation requires applications compiled
1258 with 64K aligned segments.
1259
1260 endchoice
1261
1262 choice
1263 prompt "Virtual address space size"
1264 default ARM64_VA_BITS_39 if ARM64_4K_PAGES
1265 default ARM64_VA_BITS_47 if ARM64_16K_PAGES
1266 default ARM64_VA_BITS_42 if ARM64_64K_PAGES
1267 help
1268 Allows choosing one of multiple possible virtual address
1269 space sizes. The level of translation table is determined by
1270 a combination of page size and virtual address space size.
1271
1272 config ARM64_VA_BITS_36
1273 bool "36-bit" if EXPERT
1274 depends on ARM64_16K_PAGES
1275
1276 config ARM64_VA_BITS_39
1277 bool "39-bit"
1278 depends on ARM64_4K_PAGES
1279
1280 config ARM64_VA_BITS_42
1281 bool "42-bit"
1282 depends on ARM64_64K_PAGES
1283
1284 config ARM64_VA_BITS_47
1285 bool "47-bit"
1286 depends on ARM64_16K_PAGES
1287
1288 config ARM64_VA_BITS_48
1289 bool "48-bit"
1290
1291 config ARM64_VA_BITS_52
1292 bool "52-bit"
1293 depends on ARM64_64K_PAGES && (ARM64_PAN || !ARM64_SW_TTBR0_PAN)
1294 help
1295 Enable 52-bit virtual addressing for userspace when explicitly
1296 requested via a hint to mmap(). The kernel will also use 52-bit
1297 virtual addresses for its own mappings (provided HW support for
1298 this feature is available, otherwise it reverts to 48-bit).
1299
1300 NOTE: Enabling 52-bit virtual addressing in conjunction with
1301 ARMv8.3 Pointer Authentication will result in the PAC being
1302 reduced from 7 bits to 3 bits, which may have a significant
1303 impact on its susceptibility to brute-force attacks.
1304
1305 If unsure, select 48-bit virtual addressing instead.
1306
1307 endchoice
1308
1309 config ARM64_FORCE_52BIT
1310 bool "Force 52-bit virtual addresses for userspace"
1311 depends on ARM64_VA_BITS_52 && EXPERT
1312 help
1313 For systems with 52-bit userspace VAs enabled, the kernel will attempt
1314 to maintain compatibility with older software by providing 48-bit VAs
1315 unless a hint is supplied to mmap.
1316
1317 This configuration option disables the 48-bit compatibility logic, and
1318 forces all userspace addresses to be 52-bit on HW that supports it. One
1319 should only enable this configuration option for stress testing userspace
1320 memory management code. If unsure say N here.
1321
1322 config ARM64_VA_BITS
1323 int
1324 default 36 if ARM64_VA_BITS_36
1325 default 39 if ARM64_VA_BITS_39
1326 default 42 if ARM64_VA_BITS_42
1327 default 47 if ARM64_VA_BITS_47
1328 default 48 if ARM64_VA_BITS_48
1329 default 52 if ARM64_VA_BITS_52
1330
1331 choice
1332 prompt "Physical address space size"
1333 default ARM64_PA_BITS_48
1334 help
1335 Choose the maximum physical address range that the kernel will
1336 support.
1337
1338 config ARM64_PA_BITS_48
1339 bool "48-bit"
1340
1341 config ARM64_PA_BITS_52
1342 bool "52-bit (ARMv8.2)"
1343 depends on ARM64_64K_PAGES
1344 depends on ARM64_PAN || !ARM64_SW_TTBR0_PAN
1345 help
1346 Enable support for a 52-bit physical address space, introduced as
1347 part of the ARMv8.2-LPA extension.
1348
1349 With this enabled, the kernel will also continue to work on CPUs that
1350 do not support ARMv8.2-LPA, but with some added memory overhead (and
1351 minor performance overhead).
1352
1353 endchoice
1354
1355 config ARM64_PA_BITS
1356 int
1357 default 48 if ARM64_PA_BITS_48
1358 default 52 if ARM64_PA_BITS_52
1359
1360 choice
1361 prompt "Endianness"
1362 default CPU_LITTLE_ENDIAN
1363 help
1364 Select the endianness of data accesses performed by the CPU. Userspace
1365 applications will need to be compiled and linked for the endianness
1366 that is selected here.
1367
1368 config CPU_BIG_ENDIAN
1369 bool "Build big-endian kernel"
1370 depends on !LD_IS_LLD || LLD_VERSION >= 130000
1371 help
1372 Say Y if you plan on running a kernel with a big-endian userspace.
1373
1374 config CPU_LITTLE_ENDIAN
1375 bool "Build little-endian kernel"
1376 help
1377 Say Y if you plan on running a kernel with a little-endian userspace.
1378 This is usually the case for distributions targeting arm64.
1379
1380 endchoice
1381
1382 config SCHED_MC
1383 bool "Multi-core scheduler support"
1384 help
1385 Multi-core scheduler support improves the CPU scheduler's decision
1386 making when dealing with multi-core CPU chips at a cost of slightly
1387 increased overhead in some places. If unsure say N here.
1388
1389 config SCHED_CLUSTER
1390 bool "Cluster scheduler support"
1391 help
1392 Cluster scheduler support improves the CPU scheduler's decision
1393 making when dealing with machines that have clusters of CPUs.
1394 Cluster usually means a couple of CPUs which are placed closely
1395 by sharing mid-level caches, last-level cache tags or internal
1396 busses.
1397
1398 config SCHED_SMT
1399 bool "SMT scheduler support"
1400 help
1401 Improves the CPU scheduler's decision making when dealing with
1402 MultiThreading at a cost of slightly increased overhead in some
1403 places. If unsure say N here.
1404
1405 config NR_CPUS
1406 int "Maximum number of CPUs (2-4096)"
1407 range 2 4096
1408 default "256"
1409
1410 config HOTPLUG_CPU
1411 bool "Support for hot-pluggable CPUs"
1412 select GENERIC_IRQ_MIGRATION
1413 help
1414 Say Y here to experiment with turning CPUs off and on. CPUs
1415 can be controlled through /sys/devices/system/cpu.
1416
1417 # Common NUMA Features
1418 config NUMA
1419 bool "NUMA Memory Allocation and Scheduler Support"
1420 select GENERIC_ARCH_NUMA
1421 select ACPI_NUMA if ACPI
1422 select OF_NUMA
1423 select HAVE_SETUP_PER_CPU_AREA
1424 select NEED_PER_CPU_EMBED_FIRST_CHUNK
1425 select NEED_PER_CPU_PAGE_FIRST_CHUNK
1426 select USE_PERCPU_NUMA_NODE_ID
1427 help
1428 Enable NUMA (Non-Uniform Memory Access) support.
1429
1430 The kernel will try to allocate memory used by a CPU on the
1431 local memory of the CPU and add some more
1432 NUMA awareness to the kernel.
1433
1434 config NODES_SHIFT
1435 int "Maximum NUMA Nodes (as a power of 2)"
1436 range 1 10
1437 default "4"
1438 depends on NUMA
1439 help
1440 Specify the maximum number of NUMA Nodes available on the target
1441 system. Increases memory reserved to accommodate various tables.
1442
1443 source "kernel/Kconfig.hz"
1444
1445 config ARCH_SPARSEMEM_ENABLE
1446 def_bool y
1447 select SPARSEMEM_VMEMMAP_ENABLE
1448 select SPARSEMEM_VMEMMAP
1449
1450 config HW_PERF_EVENTS
1451 def_bool y
1452 depends on ARM_PMU
1453
1454 # Supported by clang >= 7.0 or GCC >= 12.0.0
1455 config CC_HAVE_SHADOW_CALL_STACK
1456 def_bool $(cc-option, -fsanitize=shadow-call-stack -ffixed-x18)
1457
1458 config PARAVIRT
1459 bool "Enable paravirtualization code"
1460 help
1461 This changes the kernel so it can modify itself when it is run
1462 under a hypervisor, potentially improving performance significantly
1463 over full virtualization.
1464
1465 config PARAVIRT_TIME_ACCOUNTING
1466 bool "Paravirtual steal time accounting"
1467 select PARAVIRT
1468 help
1469 Select this option to enable fine granularity task steal time
1470 accounting. Time spent executing other tasks in parallel with
1471 the current vCPU is discounted from the vCPU power. To account for
1472 that, there can be a small performance impact.
1473
1474 If in doubt, say N here.
1475
1476 config ARCH_SUPPORTS_KEXEC
1477 def_bool PM_SLEEP_SMP
1478
1479 config ARCH_SUPPORTS_KEXEC_FILE
1480 def_bool y
1481
1482 config ARCH_SELECTS_KEXEC_FILE
1483 def_bool y
1484 depends on KEXEC_FILE
1485 select HAVE_IMA_KEXEC if IMA
1486
1487 config ARCH_SUPPORTS_KEXEC_SIG
1488 def_bool y
1489
1490 config ARCH_SUPPORTS_KEXEC_IMAGE_VERIFY_SIG
1491 def_bool y
1492
1493 config ARCH_DEFAULT_KEXEC_IMAGE_VERIFY_SIG
1494 def_bool y
1495
1496 config ARCH_SUPPORTS_CRASH_DUMP
1497 def_bool y
1498
1499 config TRANS_TABLE
1500 def_bool y
1501 depends on HIBERNATION || KEXEC_CORE
1502
1503 config XEN_DOM0
1504 def_bool y
1505 depends on XEN
1506
1507 config XEN
1508 bool "Xen guest support on ARM64"
1509 depends on ARM64 && OF
1510 select SWIOTLB_XEN
1511 select PARAVIRT
1512 help
1513 Say Y if you want to run Linux in a Virtual Machine on Xen on ARM64.
1514
1515 # include/linux/mmzone.h requires the following to be true:
1516 #
1517 # MAX_ORDER + PAGE_SHIFT <= SECTION_SIZE_BITS
1518 #
1519 # so the maximum value of MAX_ORDER is SECTION_SIZE_BITS - PAGE_SHIFT:
1520 #
1521 # | SECTION_SIZE_BITS | PAGE_SHIFT | max MAX_ORDER | default MAX_ORDER |
1522 # ----+-------------------+--------------+-----------------+--------------------+
1523 # 4K | 27 | 12 | 15 | 10 |
1524 # 16K | 27 | 14 | 13 | 11 |
1525 # 64K | 29 | 16 | 13 | 13 |
1526 config ARCH_FORCE_MAX_ORDER
1527 int
1528 default "13" if ARM64_64K_PAGES
1529 default "11" if ARM64_16K_PAGES
1530 default "10"
1531 help
1532 The kernel page allocator limits the size of maximal physically
1533 contiguous allocations. The limit is called MAX_ORDER and it
1534 defines the maximal power of two of number of pages that can be
1535 allocated as a single contiguous block. This option allows
1536 overriding the default setting when ability to allocate very
1537 large blocks of physically contiguous memory is required.
1538
1539 The maximal size of allocation cannot exceed the size of the
1540 section, so the value of MAX_ORDER should satisfy
1541
1542 MAX_ORDER + PAGE_SHIFT <= SECTION_SIZE_BITS
1543
1544 Don't change if unsure.
1545
1546 config UNMAP_KERNEL_AT_EL0
1547 bool "Unmap kernel when running in userspace (aka \"KAISER\")" if EXPERT
1548 default y
1549 help
1550 Speculation attacks against some high-performance processors can
1551 be used to bypass MMU permission checks and leak kernel data to
1552 userspace. This can be defended against by unmapping the kernel
1553 when running in userspace, mapping it back in on exception entry
1554 via a trampoline page in the vector table.
1555
1556 If unsure, say Y.
1557
1558 config MITIGATE_SPECTRE_BRANCH_HISTORY
1559 bool "Mitigate Spectre style attacks against branch history" if EXPERT
1560 default y
1561 help
1562 Speculation attacks against some high-performance processors can
1563 make use of branch history to influence future speculation.
1564 When taking an exception from user-space, a sequence of branches
1565 or a firmware call overwrites the branch history.
1566
1567 config RODATA_FULL_DEFAULT_ENABLED
1568 bool "Apply r/o permissions of VM areas also to their linear aliases"
1569 default y
1570 help
1571 Apply read-only attributes of VM areas to the linear alias of
1572 the backing pages as well. This prevents code or read-only data
1573 from being modified (inadvertently or intentionally) via another
1574 mapping of the same memory page. This additional enhancement can
1575 be turned off at runtime by passing rodata=[off|on] (and turned on
1576 with rodata=full if this option is set to 'n')
1577
1578 This requires the linear region to be mapped down to pages,
1579 which may adversely affect performance in some cases.
1580
1581 config ARM64_SW_TTBR0_PAN
1582 bool "Emulate Privileged Access Never using TTBR0_EL1 switching"
1583 help
1584 Enabling this option prevents the kernel from accessing
1585 user-space memory directly by pointing TTBR0_EL1 to a reserved
1586 zeroed area and reserved ASID. The user access routines
1587 restore the valid TTBR0_EL1 temporarily.
1588
1589 config ARM64_TAGGED_ADDR_ABI
1590 bool "Enable the tagged user addresses syscall ABI"
1591 default y
1592 help
1593 When this option is enabled, user applications can opt in to a
1594 relaxed ABI via prctl() allowing tagged addresses to be passed
1595 to system calls as pointer arguments. For details, see
1596 Documentation/arch/arm64/tagged-address-abi.rst.
1597
1598 menuconfig COMPAT
1599 bool "Kernel support for 32-bit EL0"
1600 depends on ARM64_4K_PAGES || EXPERT
1601 select HAVE_UID16
1602 select OLD_SIGSUSPEND3
1603 select COMPAT_OLD_SIGACTION
1604 help
1605 This option enables support for a 32-bit EL0 running under a 64-bit
1606 kernel at EL1. AArch32-specific components such as system calls,
1607 the user helper functions, VFP support and the ptrace interface are
1608 handled appropriately by the kernel.
1609
1610 If you use a page size other than 4KB (i.e, 16KB or 64KB), please be aware
1611 that you will only be able to execute AArch32 binaries that were compiled
1612 with page size aligned segments.
1613
1614 If you want to execute 32-bit userspace applications, say Y.
1615
1616 if COMPAT
1617
1618 config KUSER_HELPERS
1619 bool "Enable kuser helpers page for 32-bit applications"
1620 default y
1621 help
1622 Warning: disabling this option may break 32-bit user programs.
1623
1624 Provide kuser helpers to compat tasks. The kernel provides
1625 helper code to userspace in read only form at a fixed location
1626 to allow userspace to be independent of the CPU type fitted to
1627 the system. This permits binaries to be run on ARMv4 through
1628 to ARMv8 without modification.
1629
1630 See Documentation/arch/arm/kernel_user_helpers.rst for details.
1631
1632 However, the fixed address nature of these helpers can be used
1633 by ROP (return orientated programming) authors when creating
1634 exploits.
1635
1636 If all of the binaries and libraries which run on your platform
1637 are built specifically for your platform, and make no use of
1638 these helpers, then you can turn this option off to hinder
1639 such exploits. However, in that case, if a binary or library
1640 relying on those helpers is run, it will not function correctly.
1641
1642 Say N here only if you are absolutely certain that you do not
1643 need these helpers; otherwise, the safe option is to say Y.
1644
1645 config COMPAT_VDSO
1646 bool "Enable vDSO for 32-bit applications"
1647 depends on !CPU_BIG_ENDIAN
1648 depends on (CC_IS_CLANG && LD_IS_LLD) || "$(CROSS_COMPILE_COMPAT)" != ""
1649 select GENERIC_COMPAT_VDSO
1650 default y
1651 help
1652 Place in the process address space of 32-bit applications an
1653 ELF shared object providing fast implementations of gettimeofday
1654 and clock_gettime.
1655
1656 You must have a 32-bit build of glibc 2.22 or later for programs
1657 to seamlessly take advantage of this.
1658
1659 config THUMB2_COMPAT_VDSO
1660 bool "Compile the 32-bit vDSO for Thumb-2 mode" if EXPERT
1661 depends on COMPAT_VDSO
1662 default y
1663 help
1664 Compile the compat vDSO with '-mthumb -fomit-frame-pointer' if y,
1665 otherwise with '-marm'.
1666
1667 config COMPAT_ALIGNMENT_FIXUPS
1668 bool "Fix up misaligned multi-word loads and stores in user space"
1669
1670 menuconfig ARMV8_DEPRECATED
1671 bool "Emulate deprecated/obsolete ARMv8 instructions"
1672 depends on SYSCTL
1673 help
1674 Legacy software support may require certain instructions
1675 that have been deprecated or obsoleted in the architecture.
1676
1677 Enable this config to enable selective emulation of these
1678 features.
1679
1680 If unsure, say Y
1681
1682 if ARMV8_DEPRECATED
1683
1684 config SWP_EMULATION
1685 bool "Emulate SWP/SWPB instructions"
1686 help
1687 ARMv8 obsoletes the use of A32 SWP/SWPB instructions such that
1688 they are always undefined. Say Y here to enable software
1689 emulation of these instructions for userspace using LDXR/STXR.
1690 This feature can be controlled at runtime with the abi.swp
1691 sysctl which is disabled by default.
1692
1693 In some older versions of glibc [<=2.8] SWP is used during futex
1694 trylock() operations with the assumption that the code will not
1695 be preempted. This invalid assumption may be more likely to fail
1696 with SWP emulation enabled, leading to deadlock of the user
1697 application.
1698
1699 NOTE: when accessing uncached shared regions, LDXR/STXR rely
1700 on an external transaction monitoring block called a global
1701 monitor to maintain update atomicity. If your system does not
1702 implement a global monitor, this option can cause programs that
1703 perform SWP operations to uncached memory to deadlock.
1704
1705 If unsure, say Y
1706
1707 config CP15_BARRIER_EMULATION
1708 bool "Emulate CP15 Barrier instructions"
1709 help
1710 The CP15 barrier instructions - CP15ISB, CP15DSB, and
1711 CP15DMB - are deprecated in ARMv8 (and ARMv7). It is
1712 strongly recommended to use the ISB, DSB, and DMB
1713 instructions instead.
1714
1715 Say Y here to enable software emulation of these
1716 instructions for AArch32 userspace code. When this option is
1717 enabled, CP15 barrier usage is traced which can help
1718 identify software that needs updating. This feature can be
1719 controlled at runtime with the abi.cp15_barrier sysctl.
1720
1721 If unsure, say Y
1722
1723 config SETEND_EMULATION
1724 bool "Emulate SETEND instruction"
1725 help
1726 The SETEND instruction alters the data-endianness of the
1727 AArch32 EL0, and is deprecated in ARMv8.
1728
1729 Say Y here to enable software emulation of the instruction
1730 for AArch32 userspace code. This feature can be controlled
1731 at runtime with the abi.setend sysctl.
1732
1733 Note: All the cpus on the system must have mixed endian support at EL0
1734 for this feature to be enabled. If a new CPU - which doesn't support mixed
1735 endian - is hotplugged in after this feature has been enabled, there could
1736 be unexpected results in the applications.
1737
1738 If unsure, say Y
1739 endif # ARMV8_DEPRECATED
1740
1741 endif # COMPAT
1742
1743 menu "ARMv8.1 architectural features"
1744
1745 config ARM64_HW_AFDBM
1746 bool "Support for hardware updates of the Access and Dirty page flags"
1747 default y
1748 help
1749 The ARMv8.1 architecture extensions introduce support for
1750 hardware updates of the access and dirty information in page
1751 table entries. When enabled in TCR_EL1 (HA and HD bits) on
1752 capable processors, accesses to pages with PTE_AF cleared will
1753 set this bit instead of raising an access flag fault.
1754 Similarly, writes to read-only pages with the DBM bit set will
1755 clear the read-only bit (AP[2]) instead of raising a
1756 permission fault.
1757
1758 Kernels built with this configuration option enabled continue
1759 to work on pre-ARMv8.1 hardware and the performance impact is
1760 minimal. If unsure, say Y.
1761
1762 config ARM64_PAN
1763 bool "Enable support for Privileged Access Never (PAN)"
1764 default y
1765 help
1766 Privileged Access Never (PAN; part of the ARMv8.1 Extensions)
1767 prevents the kernel or hypervisor from accessing user-space (EL0)
1768 memory directly.
1769
1770 Choosing this option will cause any unprotected (not using
1771 copy_to_user et al) memory access to fail with a permission fault.
1772
1773 The feature is detected at runtime, and will remain as a 'nop'
1774 instruction if the cpu does not implement the feature.
1775
1776 config AS_HAS_LSE_ATOMICS
1777 def_bool $(as-instr,.arch_extension lse)
1778
1779 config ARM64_LSE_ATOMICS
1780 bool
1781 default ARM64_USE_LSE_ATOMICS
1782 depends on AS_HAS_LSE_ATOMICS
1783
1784 config ARM64_USE_LSE_ATOMICS
1785 bool "Atomic instructions"
1786 default y
1787 help
1788 As part of the Large System Extensions, ARMv8.1 introduces new
1789 atomic instructions that are designed specifically to scale in
1790 very large systems.
1791
1792 Say Y here to make use of these instructions for the in-kernel
1793 atomic routines. This incurs a small overhead on CPUs that do
1794 not support these instructions and requires the kernel to be
1795 built with binutils >= 2.25 in order for the new instructions
1796 to be used.
1797
1798 endmenu # "ARMv8.1 architectural features"
1799
1800 menu "ARMv8.2 architectural features"
1801
1802 config AS_HAS_ARMV8_2
1803 def_bool $(cc-option,-Wa$(comma)-march=armv8.2-a)
1804
1805 config AS_HAS_SHA3
1806 def_bool $(as-instr,.arch armv8.2-a+sha3)
1807
1808 config ARM64_PMEM
1809 bool "Enable support for persistent memory"
1810 select ARCH_HAS_PMEM_API
1811 select ARCH_HAS_UACCESS_FLUSHCACHE
1812 help
1813 Say Y to enable support for the persistent memory API based on the
1814 ARMv8.2 DCPoP feature.
1815
1816 The feature is detected at runtime, and the kernel will use DC CVAC
1817 operations if DC CVAP is not supported (following the behaviour of
1818 DC CVAP itself if the system does not define a point of persistence).
1819
1820 config ARM64_RAS_EXTN
1821 bool "Enable support for RAS CPU Extensions"
1822 default y
1823 help
1824 CPUs that support the Reliability, Availability and Serviceability
1825 (RAS) Extensions, part of ARMv8.2 are able to track faults and
1826 errors, classify them and report them to software.
1827
1828 On CPUs with these extensions system software can use additional
1829 barriers to determine if faults are pending and read the
1830 classification from a new set of registers.
1831
1832 Selecting this feature will allow the kernel to use these barriers
1833 and access the new registers if the system supports the extension.
1834 Platform RAS features may additionally depend on firmware support.
1835
1836 config ARM64_CNP
1837 bool "Enable support for Common Not Private (CNP) translations"
1838 default y
1839 depends on ARM64_PAN || !ARM64_SW_TTBR0_PAN
1840 help
1841 Common Not Private (CNP) allows translation table entries to
1842 be shared between different PEs in the same inner shareable
1843 domain, so the hardware can use this fact to optimise the
1844 caching of such entries in the TLB.
1845
1846 Selecting this option allows the CNP feature to be detected
1847 at runtime, and does not affect PEs that do not implement
1848 this feature.
1849
1850 endmenu # "ARMv8.2 architectural features"
1851
1852 menu "ARMv8.3 architectural features"
1853
1854 config ARM64_PTR_AUTH
1855 bool "Enable support for pointer authentication"
1856 default y
1857 help
1858 Pointer authentication (part of the ARMv8.3 Extensions) provides
1859 instructions for signing and authenticating pointers against secret
1860 keys, which can be used to mitigate Return Oriented Programming (ROP)
1861 and other attacks.
1862
1863 This option enables these instructions at EL0 (i.e. for userspace).
1864 Choosing this option will cause the kernel to initialise secret keys
1865 for each process at exec() time, with these keys being
1866 context-switched along with the process.
1867
1868 The feature is detected at runtime. If the feature is not present in
1869 hardware it will not be advertised to userspace/KVM guest nor will it
1870 be enabled.
1871
1872 If the feature is present on the boot CPU but not on a late CPU, then
1873 the late CPU will be parked. Also, if the boot CPU does not have
1874 address auth and the late CPU has then the late CPU will still boot
1875 but with the feature disabled. On such a system, this option should
1876 not be selected.
1877
1878 config ARM64_PTR_AUTH_KERNEL
1879 bool "Use pointer authentication for kernel"
1880 default y
1881 depends on ARM64_PTR_AUTH
1882 depends on (CC_HAS_SIGN_RETURN_ADDRESS || CC_HAS_BRANCH_PROT_PAC_RET) && AS_HAS_ARMV8_3
1883 # Modern compilers insert a .note.gnu.property section note for PAC
1884 # which is only understood by binutils starting with version 2.33.1.
1885 depends on LD_IS_LLD || LD_VERSION >= 23301 || (CC_IS_GCC && GCC_VERSION < 90100)
1886 depends on !CC_IS_CLANG || AS_HAS_CFI_NEGATE_RA_STATE
1887 depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_ARGS)
1888 help
1889 If the compiler supports the -mbranch-protection or
1890 -msign-return-address flag (e.g. GCC 7 or later), then this option
1891 will cause the kernel itself to be compiled with return address
1892 protection. In this case, and if the target hardware is known to
1893 support pointer authentication, then CONFIG_STACKPROTECTOR can be
1894 disabled with minimal loss of protection.
1895
1896 This feature works with FUNCTION_GRAPH_TRACER option only if
1897 DYNAMIC_FTRACE_WITH_ARGS is enabled.
1898
1899 config CC_HAS_BRANCH_PROT_PAC_RET
1900 # GCC 9 or later, clang 8 or later
1901 def_bool $(cc-option,-mbranch-protection=pac-ret+leaf)
1902
1903 config CC_HAS_SIGN_RETURN_ADDRESS
1904 # GCC 7, 8
1905 def_bool $(cc-option,-msign-return-address=all)
1906
1907 config AS_HAS_ARMV8_3
1908 def_bool $(cc-option,-Wa$(comma)-march=armv8.3-a)
1909
1910 config AS_HAS_CFI_NEGATE_RA_STATE
1911 def_bool $(as-instr,.cfi_startproc\n.cfi_negate_ra_state\n.cfi_endproc\n)
1912
1913 config AS_HAS_LDAPR
1914 def_bool $(as-instr,.arch_extension rcpc)
1915
1916 endmenu # "ARMv8.3 architectural features"
1917
1918 menu "ARMv8.4 architectural features"
1919
1920 config ARM64_AMU_EXTN
1921 bool "Enable support for the Activity Monitors Unit CPU extension"
1922 default y
1923 help
1924 The activity monitors extension is an optional extension introduced
1925 by the ARMv8.4 CPU architecture. This enables support for version 1
1926 of the activity monitors architecture, AMUv1.
1927
1928 To enable the use of this extension on CPUs that implement it, say Y.
1929
1930 Note that for architectural reasons, firmware _must_ implement AMU
1931 support when running on CPUs that present the activity monitors
1932 extension. The required support is present in:
1933 * Version 1.5 and later of the ARM Trusted Firmware
1934
1935 For kernels that have this configuration enabled but boot with broken
1936 firmware, you may need to say N here until the firmware is fixed.
1937 Otherwise you may experience firmware panics or lockups when
1938 accessing the counter registers. Even if you are not observing these
1939 symptoms, the values returned by the register reads might not
1940 correctly reflect reality. Most commonly, the value read will be 0,
1941 indicating that the counter is not enabled.
1942
1943 config AS_HAS_ARMV8_4
1944 def_bool $(cc-option,-Wa$(comma)-march=armv8.4-a)
1945
1946 config ARM64_TLB_RANGE
1947 bool "Enable support for tlbi range feature"
1948 default y
1949 depends on AS_HAS_ARMV8_4
1950 help
1951 ARMv8.4-TLBI provides TLBI invalidation instruction that apply to a
1952 range of input addresses.
1953
1954 The feature introduces new assembly instructions, and they were
1955 support when binutils >= 2.30.
1956
1957 endmenu # "ARMv8.4 architectural features"
1958
1959 menu "ARMv8.5 architectural features"
1960
1961 config AS_HAS_ARMV8_5
1962 def_bool $(cc-option,-Wa$(comma)-march=armv8.5-a)
1963
1964 config ARM64_BTI
1965 bool "Branch Target Identification support"
1966 default y
1967 help
1968 Branch Target Identification (part of the ARMv8.5 Extensions)
1969 provides a mechanism to limit the set of locations to which computed
1970 branch instructions such as BR or BLR can jump.
1971
1972 To make use of BTI on CPUs that support it, say Y.
1973
1974 BTI is intended to provide complementary protection to other control
1975 flow integrity protection mechanisms, such as the Pointer
1976 authentication mechanism provided as part of the ARMv8.3 Extensions.
1977 For this reason, it does not make sense to enable this option without
1978 also enabling support for pointer authentication. Thus, when
1979 enabling this option you should also select ARM64_PTR_AUTH=y.
1980
1981 Userspace binaries must also be specifically compiled to make use of
1982 this mechanism. If you say N here or the hardware does not support
1983 BTI, such binaries can still run, but you get no additional
1984 enforcement of branch destinations.
1985
1986 config ARM64_BTI_KERNEL
1987 bool "Use Branch Target Identification for kernel"
1988 default y
1989 depends on ARM64_BTI
1990 depends on ARM64_PTR_AUTH_KERNEL
1991 depends on CC_HAS_BRANCH_PROT_PAC_RET_BTI
1992 # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94697
1993 depends on !CC_IS_GCC || GCC_VERSION >= 100100
1994 # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106671
1995 depends on !CC_IS_GCC
1996 # https://github.com/llvm/llvm-project/commit/a88c722e687e6780dcd6a58718350dc76fcc4cc9
1997 depends on !CC_IS_CLANG || CLANG_VERSION >= 120000
1998 depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_ARGS)
1999 help
2000 Build the kernel with Branch Target Identification annotations
2001 and enable enforcement of this for kernel code. When this option
2002 is enabled and the system supports BTI all kernel code including
2003 modular code must have BTI enabled.
2004
2005 config CC_HAS_BRANCH_PROT_PAC_RET_BTI
2006 # GCC 9 or later, clang 8 or later
2007 def_bool $(cc-option,-mbranch-protection=pac-ret+leaf+bti)
2008
2009 config ARM64_E0PD
2010 bool "Enable support for E0PD"
2011 default y
2012 help
2013 E0PD (part of the ARMv8.5 extensions) allows us to ensure
2014 that EL0 accesses made via TTBR1 always fault in constant time,
2015 providing similar benefits to KASLR as those provided by KPTI, but
2016 with lower overhead and without disrupting legitimate access to
2017 kernel memory such as SPE.
2018
2019 This option enables E0PD for TTBR1 where available.
2020
2021 config ARM64_AS_HAS_MTE
2022 # Initial support for MTE went in binutils 2.32.0, checked with
2023 # ".arch armv8.5-a+memtag" below. However, this was incomplete
2024 # as a late addition to the final architecture spec (LDGM/STGM)
2025 # is only supported in the newer 2.32.x and 2.33 binutils
2026 # versions, hence the extra "stgm" instruction check below.
2027 def_bool $(as-instr,.arch armv8.5-a+memtag\nstgm xzr$(comma)[x0])
2028
2029 config ARM64_MTE
2030 bool "Memory Tagging Extension support"
2031 default y
2032 depends on ARM64_AS_HAS_MTE && ARM64_TAGGED_ADDR_ABI
2033 depends on AS_HAS_ARMV8_5
2034 depends on AS_HAS_LSE_ATOMICS
2035 # Required for tag checking in the uaccess routines
2036 depends on ARM64_PAN
2037 select ARCH_HAS_SUBPAGE_FAULTS
2038 select ARCH_USES_HIGH_VMA_FLAGS
2039 select ARCH_USES_PG_ARCH_X
2040 help
2041 Memory Tagging (part of the ARMv8.5 Extensions) provides
2042 architectural support for run-time, always-on detection of
2043 various classes of memory error to aid with software debugging
2044 to eliminate vulnerabilities arising from memory-unsafe
2045 languages.
2046
2047 This option enables the support for the Memory Tagging
2048 Extension at EL0 (i.e. for userspace).
2049
2050 Selecting this option allows the feature to be detected at
2051 runtime. Any secondary CPU not implementing this feature will
2052 not be allowed a late bring-up.
2053
2054 Userspace binaries that want to use this feature must
2055 explicitly opt in. The mechanism for the userspace is
2056 described in:
2057
2058 Documentation/arch/arm64/memory-tagging-extension.rst.
2059
2060 endmenu # "ARMv8.5 architectural features"
2061
2062 menu "ARMv8.7 architectural features"
2063
2064 config ARM64_EPAN
2065 bool "Enable support for Enhanced Privileged Access Never (EPAN)"
2066 default y
2067 depends on ARM64_PAN
2068 help
2069 Enhanced Privileged Access Never (EPAN) allows Privileged
2070 Access Never to be used with Execute-only mappings.
2071
2072 The feature is detected at runtime, and will remain disabled
2073 if the cpu does not implement the feature.
2074 endmenu # "ARMv8.7 architectural features"
2075
2076 config ARM64_SVE
2077 bool "ARM Scalable Vector Extension support"
2078 default y
2079 help
2080 The Scalable Vector Extension (SVE) is an extension to the AArch64
2081 execution state which complements and extends the SIMD functionality
2082 of the base architecture to support much larger vectors and to enable
2083 additional vectorisation opportunities.
2084
2085 To enable use of this extension on CPUs that implement it, say Y.
2086
2087 On CPUs that support the SVE2 extensions, this option will enable
2088 those too.
2089
2090 Note that for architectural reasons, firmware _must_ implement SVE
2091 support when running on SVE capable hardware. The required support
2092 is present in:
2093
2094 * version 1.5 and later of the ARM Trusted Firmware
2095 * the AArch64 boot wrapper since commit 5e1261e08abf
2096 ("bootwrapper: SVE: Enable SVE for EL2 and below").
2097
2098 For other firmware implementations, consult the firmware documentation
2099 or vendor.
2100
2101 If you need the kernel to boot on SVE-capable hardware with broken
2102 firmware, you may need to say N here until you get your firmware
2103 fixed. Otherwise, you may experience firmware panics or lockups when
2104 booting the kernel. If unsure and you are not observing these
2105 symptoms, you should assume that it is safe to say Y.
2106
2107 config ARM64_SME
2108 bool "ARM Scalable Matrix Extension support"
2109 default y
2110 depends on ARM64_SVE
2111 help
2112 The Scalable Matrix Extension (SME) is an extension to the AArch64
2113 execution state which utilises a substantial subset of the SVE
2114 instruction set, together with the addition of new architectural
2115 register state capable of holding two dimensional matrix tiles to
2116 enable various matrix operations.
2117
2118 config ARM64_PSEUDO_NMI
2119 bool "Support for NMI-like interrupts"
2120 select ARM_GIC_V3
2121 help
2122 Adds support for mimicking Non-Maskable Interrupts through the use of
2123 GIC interrupt priority. This support requires version 3 or later of
2124 ARM GIC.
2125
2126 This high priority configuration for interrupts needs to be
2127 explicitly enabled by setting the kernel parameter
2128 "irqchip.gicv3_pseudo_nmi" to 1.
2129
2130 If unsure, say N
2131
2132 if ARM64_PSEUDO_NMI
2133 config ARM64_DEBUG_PRIORITY_MASKING
2134 bool "Debug interrupt priority masking"
2135 help
2136 This adds runtime checks to functions enabling/disabling
2137 interrupts when using priority masking. The additional checks verify
2138 the validity of ICC_PMR_EL1 when calling concerned functions.
2139
2140 If unsure, say N
2141 endif # ARM64_PSEUDO_NMI
2142
2143 config RELOCATABLE
2144 bool "Build a relocatable kernel image" if EXPERT
2145 select ARCH_HAS_RELR
2146 default y
2147 help
2148 This builds the kernel as a Position Independent Executable (PIE),
2149 which retains all relocation metadata required to relocate the
2150 kernel binary at runtime to a different virtual address than the
2151 address it was linked at.
2152 Since AArch64 uses the RELA relocation format, this requires a
2153 relocation pass at runtime even if the kernel is loaded at the
2154 same address it was linked at.
2155
2156 config RANDOMIZE_BASE
2157 bool "Randomize the address of the kernel image"
2158 select RELOCATABLE
2159 help
2160 Randomizes the virtual address at which the kernel image is
2161 loaded, as a security feature that deters exploit attempts
2162 relying on knowledge of the location of kernel internals.
2163
2164 It is the bootloader's job to provide entropy, by passing a
2165 random u64 value in /chosen/kaslr-seed at kernel entry.
2166
2167 When booting via the UEFI stub, it will invoke the firmware's
2168 EFI_RNG_PROTOCOL implementation (if available) to supply entropy
2169 to the kernel proper. In addition, it will randomise the physical
2170 location of the kernel Image as well.
2171
2172 If unsure, say N.
2173
2174 config RANDOMIZE_MODULE_REGION_FULL
2175 bool "Randomize the module region over a 2 GB range"
2176 depends on RANDOMIZE_BASE
2177 default y
2178 help
2179 Randomizes the location of the module region inside a 2 GB window
2180 covering the core kernel. This way, it is less likely for modules
2181 to leak information about the location of core kernel data structures
2182 but it does imply that function calls between modules and the core
2183 kernel will need to be resolved via veneers in the module PLT.
2184
2185 When this option is not set, the module region will be randomized over
2186 a limited range that contains the [_stext, _etext] interval of the
2187 core kernel, so branch relocations are almost always in range unless
2188 the region is exhausted. In this particular case of region
2189 exhaustion, modules might be able to fall back to a larger 2GB area.
2190
2191 config CC_HAVE_STACKPROTECTOR_SYSREG
2192 def_bool $(cc-option,-mstack-protector-guard=sysreg -mstack-protector-guard-reg=sp_el0 -mstack-protector-guard-offset=0)
2193
2194 config STACKPROTECTOR_PER_TASK
2195 def_bool y
2196 depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_SYSREG
2197
2198 config UNWIND_PATCH_PAC_INTO_SCS
2199 bool "Enable shadow call stack dynamically using code patching"
2200 # needs Clang with https://reviews.llvm.org/D111780 incorporated
2201 depends on CC_IS_CLANG && CLANG_VERSION >= 150000
2202 depends on ARM64_PTR_AUTH_KERNEL && CC_HAS_BRANCH_PROT_PAC_RET
2203 depends on SHADOW_CALL_STACK
2204 select UNWIND_TABLES
2205 select DYNAMIC_SCS
2206
2207 endmenu # "Kernel Features"
2208
2209 menu "Boot options"
2210
2211 config ARM64_ACPI_PARKING_PROTOCOL
2212 bool "Enable support for the ARM64 ACPI parking protocol"
2213 depends on ACPI
2214 help
2215 Enable support for the ARM64 ACPI parking protocol. If disabled
2216 the kernel will not allow booting through the ARM64 ACPI parking
2217 protocol even if the corresponding data is present in the ACPI
2218 MADT table.
2219
2220 config CMDLINE
2221 string "Default kernel command string"
2222 default ""
2223 help
2224 Provide a set of default command-line options at build time by
2225 entering them here. As a minimum, you should specify the the
2226 root device (e.g. root=/dev/nfs).
2227
2228 choice
2229 prompt "Kernel command line type" if CMDLINE != ""
2230 default CMDLINE_FROM_BOOTLOADER
2231 help
2232 Choose how the kernel will handle the provided default kernel
2233 command line string.
2234
2235 config CMDLINE_FROM_BOOTLOADER
2236 bool "Use bootloader kernel arguments if available"
2237 help
2238 Uses the command-line options passed by the boot loader. If
2239 the boot loader doesn't provide any, the default kernel command
2240 string provided in CMDLINE will be used.
2241
2242 config CMDLINE_FORCE
2243 bool "Always use the default kernel command string"
2244 help
2245 Always use the default kernel command string, even if the boot
2246 loader passes other arguments to the kernel.
2247 This is useful if you cannot or don't want to change the
2248 command-line options your boot loader passes to the kernel.
2249
2250 endchoice
2251
2252 config EFI_STUB
2253 bool
2254
2255 config EFI
2256 bool "UEFI runtime support"
2257 depends on OF && !CPU_BIG_ENDIAN
2258 depends on KERNEL_MODE_NEON
2259 select ARCH_SUPPORTS_ACPI
2260 select LIBFDT
2261 select UCS2_STRING
2262 select EFI_PARAMS_FROM_FDT
2263 select EFI_RUNTIME_WRAPPERS
2264 select EFI_STUB
2265 select EFI_GENERIC_STUB
2266 imply IMA_SECURE_AND_OR_TRUSTED_BOOT
2267 default y
2268 help
2269 This option provides support for runtime services provided
2270 by UEFI firmware (such as non-volatile variables, realtime
2271 clock, and platform reset). A UEFI stub is also provided to
2272 allow the kernel to be booted as an EFI application. This
2273 is only useful on systems that have UEFI firmware.
2274
2275 config DMI
2276 bool "Enable support for SMBIOS (DMI) tables"
2277 depends on EFI
2278 default y
2279 help
2280 This enables SMBIOS/DMI feature for systems.
2281
2282 This option is only useful on systems that have UEFI firmware.
2283 However, even with this option, the resultant kernel should
2284 continue to boot on existing non-UEFI platforms.
2285
2286 endmenu # "Boot options"
2287
2288 menu "Power management options"
2289
2290 source "kernel/power/Kconfig"
2291
2292 config ARCH_HIBERNATION_POSSIBLE
2293 def_bool y
2294 depends on CPU_PM
2295
2296 config ARCH_HIBERNATION_HEADER
2297 def_bool y
2298 depends on HIBERNATION
2299
2300 config ARCH_SUSPEND_POSSIBLE
2301 def_bool y
2302
2303 endmenu # "Power management options"
2304
2305 menu "CPU Power Management"
2306
2307 source "drivers/cpuidle/Kconfig"
2308
2309 source "drivers/cpufreq/Kconfig"
2310
2311 endmenu # "CPU Power Management"
2312
2313 source "drivers/acpi/Kconfig"
2314
2315 source "arch/arm64/kvm/Kconfig"
2316