Merge tag 'pci-v6.16-fixes-3' of git://git.kernel.org/pub/scm/linux/kernel/git/pci/pci
[linux-2.6-block.git] / arch / arm64 / Kconfig
... / ...
CommitLineData
1# SPDX-License-Identifier: GPL-2.0-only
2config 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_HOTPLUG_CPU if ACPI_PROCESSOR && HOTPLUG_CPU
9 select ACPI_IORT if ACPI
10 select ACPI_REDUCED_HARDWARE_ONLY if ACPI
11 select ACPI_MCFG if (ACPI && PCI)
12 select ACPI_SPCR_TABLE if ACPI
13 select ACPI_PPTT if ACPI
14 select ARCH_HAS_DEBUG_WX
15 select ARCH_BINFMT_ELF_EXTRA_PHDRS
16 select ARCH_BINFMT_ELF_STATE
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_CC_PLATFORM
24 select ARCH_HAS_CRC32
25 select ARCH_HAS_CRC_T10DIF if KERNEL_MODE_NEON
26 select ARCH_HAS_CURRENT_STACK_POINTER
27 select ARCH_HAS_DEBUG_VIRTUAL
28 select ARCH_HAS_DEBUG_VM_PGTABLE
29 select ARCH_HAS_DMA_OPS if XEN
30 select ARCH_HAS_DMA_PREP_COHERENT
31 select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI
32 select ARCH_HAS_FAST_MULTIPLIER
33 select ARCH_HAS_FORTIFY_SOURCE
34 select ARCH_HAS_GCOV_PROFILE_ALL
35 select ARCH_HAS_GIGANTIC_PAGE
36 select ARCH_HAS_KCOV
37 select ARCH_HAS_KERNEL_FPU_SUPPORT if KERNEL_MODE_NEON
38 select ARCH_HAS_KEEPINITRD
39 select ARCH_HAS_MEMBARRIER_SYNC_CORE
40 select ARCH_HAS_MEM_ENCRYPT
41 select ARCH_SUPPORTS_MSEAL_SYSTEM_MAPPINGS
42 select ARCH_HAS_NMI_SAFE_THIS_CPU_OPS
43 select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
44 select ARCH_HAS_NONLEAF_PMD_YOUNG if ARM64_HAFT
45 select ARCH_HAS_PREEMPT_LAZY
46 select ARCH_HAS_PTDUMP
47 select ARCH_HAS_PTE_DEVMAP
48 select ARCH_HAS_PTE_SPECIAL
49 select ARCH_HAS_HW_PTE_YOUNG
50 select ARCH_HAS_SETUP_DMA_OPS
51 select ARCH_HAS_SET_DIRECT_MAP
52 select ARCH_HAS_SET_MEMORY
53 select ARCH_HAS_MEM_ENCRYPT
54 select ARCH_HAS_FORCE_DMA_UNENCRYPTED
55 select ARCH_STACKWALK
56 select ARCH_HAS_STRICT_KERNEL_RWX
57 select ARCH_HAS_STRICT_MODULE_RWX
58 select ARCH_HAS_SYNC_DMA_FOR_DEVICE
59 select ARCH_HAS_SYNC_DMA_FOR_CPU
60 select ARCH_HAS_SYSCALL_WRAPPER
61 select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
62 select ARCH_HAS_ZONE_DMA_SET if EXPERT
63 select ARCH_HAVE_ELF_PROT
64 select ARCH_HAVE_NMI_SAFE_CMPXCHG
65 select ARCH_HAVE_TRACE_MMIO_ACCESS
66 select ARCH_INLINE_READ_LOCK if !PREEMPTION
67 select ARCH_INLINE_READ_LOCK_BH if !PREEMPTION
68 select ARCH_INLINE_READ_LOCK_IRQ if !PREEMPTION
69 select ARCH_INLINE_READ_LOCK_IRQSAVE if !PREEMPTION
70 select ARCH_INLINE_READ_UNLOCK if !PREEMPTION
71 select ARCH_INLINE_READ_UNLOCK_BH if !PREEMPTION
72 select ARCH_INLINE_READ_UNLOCK_IRQ if !PREEMPTION
73 select ARCH_INLINE_READ_UNLOCK_IRQRESTORE if !PREEMPTION
74 select ARCH_INLINE_WRITE_LOCK if !PREEMPTION
75 select ARCH_INLINE_WRITE_LOCK_BH if !PREEMPTION
76 select ARCH_INLINE_WRITE_LOCK_IRQ if !PREEMPTION
77 select ARCH_INLINE_WRITE_LOCK_IRQSAVE if !PREEMPTION
78 select ARCH_INLINE_WRITE_UNLOCK if !PREEMPTION
79 select ARCH_INLINE_WRITE_UNLOCK_BH if !PREEMPTION
80 select ARCH_INLINE_WRITE_UNLOCK_IRQ if !PREEMPTION
81 select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE if !PREEMPTION
82 select ARCH_INLINE_SPIN_TRYLOCK if !PREEMPTION
83 select ARCH_INLINE_SPIN_TRYLOCK_BH if !PREEMPTION
84 select ARCH_INLINE_SPIN_LOCK if !PREEMPTION
85 select ARCH_INLINE_SPIN_LOCK_BH if !PREEMPTION
86 select ARCH_INLINE_SPIN_LOCK_IRQ if !PREEMPTION
87 select ARCH_INLINE_SPIN_LOCK_IRQSAVE if !PREEMPTION
88 select ARCH_INLINE_SPIN_UNLOCK if !PREEMPTION
89 select ARCH_INLINE_SPIN_UNLOCK_BH if !PREEMPTION
90 select ARCH_INLINE_SPIN_UNLOCK_IRQ if !PREEMPTION
91 select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE if !PREEMPTION
92 select ARCH_KEEP_MEMBLOCK
93 select ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE
94 select ARCH_USE_CMPXCHG_LOCKREF
95 select ARCH_USE_GNU_PROPERTY
96 select ARCH_USE_MEMTEST
97 select ARCH_USE_QUEUED_RWLOCKS
98 select ARCH_USE_QUEUED_SPINLOCKS
99 select ARCH_USE_SYM_ANNOTATIONS
100 select ARCH_SUPPORTS_DEBUG_PAGEALLOC
101 select ARCH_SUPPORTS_HUGETLBFS
102 select ARCH_SUPPORTS_MEMORY_FAILURE
103 select ARCH_SUPPORTS_SHADOW_CALL_STACK if CC_HAVE_SHADOW_CALL_STACK
104 select ARCH_SUPPORTS_LTO_CLANG if CPU_LITTLE_ENDIAN
105 select ARCH_SUPPORTS_LTO_CLANG_THIN
106 select ARCH_SUPPORTS_CFI_CLANG
107 select ARCH_SUPPORTS_ATOMIC_RMW
108 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
109 select ARCH_SUPPORTS_NUMA_BALANCING
110 select ARCH_SUPPORTS_PAGE_TABLE_CHECK
111 select ARCH_SUPPORTS_PER_VMA_LOCK
112 select ARCH_SUPPORTS_HUGE_PFNMAP if TRANSPARENT_HUGEPAGE
113 select ARCH_SUPPORTS_RT
114 select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
115 select ARCH_WANT_COMPAT_IPC_PARSE_VERSION if COMPAT
116 select ARCH_WANT_DEFAULT_BPF_JIT
117 select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT
118 select ARCH_WANT_FRAME_POINTERS
119 select ARCH_WANT_HUGE_PMD_SHARE if ARM64_4K_PAGES || (ARM64_16K_PAGES && !ARM64_VA_BITS_36)
120 select ARCH_WANT_LD_ORPHAN_WARN
121 select ARCH_WANTS_EXECMEM_LATE
122 select ARCH_WANTS_NO_INSTR
123 select ARCH_WANTS_THP_SWAP if ARM64_4K_PAGES
124 select ARCH_HAS_UBSAN
125 select ARM_AMBA
126 select ARM_ARCH_TIMER
127 select ARM_GIC
128 select AUDIT_ARCH_COMPAT_GENERIC
129 select ARM_GIC_V2M if PCI
130 select ARM_GIC_V3
131 select ARM_GIC_V3_ITS if PCI
132 select ARM_PSCI_FW
133 select BUILDTIME_TABLE_SORT
134 select CLONE_BACKWARDS
135 select COMMON_CLK
136 select CPU_PM if (SUSPEND || CPU_IDLE)
137 select CPUMASK_OFFSTACK if NR_CPUS > 256
138 select DCACHE_WORD_ACCESS
139 select DYNAMIC_FTRACE if FUNCTION_TRACER
140 select DMA_BOUNCE_UNALIGNED_KMALLOC
141 select DMA_DIRECT_REMAP
142 select EDAC_SUPPORT
143 select FRAME_POINTER
144 select FUNCTION_ALIGNMENT_4B
145 select FUNCTION_ALIGNMENT_8B if DYNAMIC_FTRACE_WITH_CALL_OPS
146 select GENERIC_ALLOCATOR
147 select GENERIC_ARCH_TOPOLOGY
148 select GENERIC_CLOCKEVENTS_BROADCAST
149 select GENERIC_CPU_AUTOPROBE
150 select GENERIC_CPU_DEVICES
151 select GENERIC_CPU_VULNERABILITIES
152 select GENERIC_EARLY_IOREMAP
153 select GENERIC_IDLE_POLL_SETUP
154 select GENERIC_IOREMAP
155 select GENERIC_IRQ_IPI
156 select GENERIC_IRQ_KEXEC_CLEAR_VM_FORWARD
157 select GENERIC_IRQ_PROBE
158 select GENERIC_IRQ_SHOW
159 select GENERIC_IRQ_SHOW_LEVEL
160 select GENERIC_LIB_DEVMEM_IS_ALLOWED
161 select GENERIC_PCI_IOMAP
162 select GENERIC_SCHED_CLOCK
163 select GENERIC_SMP_IDLE_THREAD
164 select GENERIC_TIME_VSYSCALL
165 select GENERIC_GETTIMEOFDAY
166 select GENERIC_VDSO_DATA_STORE
167 select GENERIC_VDSO_TIME_NS
168 select HARDIRQS_SW_RESEND
169 select HAS_IOPORT
170 select HAVE_MOVE_PMD
171 select HAVE_MOVE_PUD
172 select HAVE_PCI
173 select HAVE_ACPI_APEI if (ACPI && EFI)
174 select HAVE_ALIGNED_STRUCT_PAGE
175 select HAVE_ARCH_AUDITSYSCALL
176 select HAVE_ARCH_BITREVERSE
177 select HAVE_ARCH_COMPILER_H
178 select HAVE_ARCH_HUGE_VMALLOC
179 select HAVE_ARCH_HUGE_VMAP
180 select HAVE_ARCH_JUMP_LABEL
181 select HAVE_ARCH_JUMP_LABEL_RELATIVE
182 select HAVE_ARCH_KASAN
183 select HAVE_ARCH_KASAN_VMALLOC
184 select HAVE_ARCH_KASAN_SW_TAGS
185 select HAVE_ARCH_KASAN_HW_TAGS if ARM64_MTE
186 # Some instrumentation may be unsound, hence EXPERT
187 select HAVE_ARCH_KCSAN if EXPERT
188 select HAVE_ARCH_KFENCE
189 select HAVE_ARCH_KGDB
190 select HAVE_ARCH_MMAP_RND_BITS
191 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT
192 select HAVE_ARCH_PREL32_RELOCATIONS
193 select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET
194 select HAVE_ARCH_SECCOMP_FILTER
195 select HAVE_ARCH_STACKLEAK
196 select HAVE_ARCH_THREAD_STRUCT_WHITELIST
197 select HAVE_ARCH_TRACEHOOK
198 select HAVE_ARCH_TRANSPARENT_HUGEPAGE
199 select HAVE_ARCH_VMAP_STACK
200 select HAVE_ARM_SMCCC
201 select HAVE_ASM_MODVERSIONS
202 select HAVE_EBPF_JIT
203 select HAVE_C_RECORDMCOUNT
204 select HAVE_CMPXCHG_DOUBLE
205 select HAVE_CMPXCHG_LOCAL
206 select HAVE_CONTEXT_TRACKING_USER
207 select HAVE_DEBUG_KMEMLEAK
208 select HAVE_DMA_CONTIGUOUS
209 select HAVE_DYNAMIC_FTRACE
210 select HAVE_DYNAMIC_FTRACE_WITH_ARGS \
211 if (GCC_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS || \
212 CLANG_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS)
213 select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS \
214 if DYNAMIC_FTRACE_WITH_ARGS && DYNAMIC_FTRACE_WITH_CALL_OPS
215 select HAVE_DYNAMIC_FTRACE_WITH_CALL_OPS \
216 if (DYNAMIC_FTRACE_WITH_ARGS && !CFI_CLANG && \
217 (CC_IS_CLANG || !CC_OPTIMIZE_FOR_SIZE))
218 select FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY \
219 if DYNAMIC_FTRACE_WITH_ARGS
220 select HAVE_SAMPLE_FTRACE_DIRECT
221 select HAVE_SAMPLE_FTRACE_DIRECT_MULTI
222 select HAVE_BUILDTIME_MCOUNT_SORT
223 select HAVE_EFFICIENT_UNALIGNED_ACCESS
224 select HAVE_GUP_FAST
225 select HAVE_FTRACE_GRAPH_FUNC
226 select HAVE_FTRACE_MCOUNT_RECORD
227 select HAVE_FUNCTION_TRACER
228 select HAVE_FUNCTION_ERROR_INJECTION
229 select HAVE_FUNCTION_GRAPH_FREGS
230 select HAVE_FUNCTION_GRAPH_TRACER
231 select HAVE_GCC_PLUGINS
232 select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && \
233 HW_PERF_EVENTS && HAVE_PERF_EVENTS_NMI
234 select HAVE_HW_BREAKPOINT if PERF_EVENTS
235 select HAVE_IOREMAP_PROT
236 select HAVE_IRQ_TIME_ACCOUNTING
237 select HAVE_MOD_ARCH_SPECIFIC
238 select HAVE_NMI
239 select HAVE_PERF_EVENTS
240 select HAVE_PERF_EVENTS_NMI if ARM64_PSEUDO_NMI
241 select HAVE_PERF_REGS
242 select HAVE_PERF_USER_STACK_DUMP
243 select HAVE_PREEMPT_DYNAMIC_KEY
244 select HAVE_REGS_AND_STACK_ACCESS_API
245 select HAVE_POSIX_CPU_TIMERS_TASK_WORK
246 select HAVE_FUNCTION_ARG_ACCESS_API
247 select MMU_GATHER_RCU_TABLE_FREE
248 select HAVE_RSEQ
249 select HAVE_RUST if RUSTC_SUPPORTS_ARM64
250 select HAVE_STACKPROTECTOR
251 select HAVE_SYSCALL_TRACEPOINTS
252 select HAVE_KPROBES
253 select HAVE_KRETPROBES
254 select HAVE_GENERIC_VDSO
255 select HOTPLUG_CORE_SYNC_DEAD if HOTPLUG_CPU
256 select HOTPLUG_SMT if HOTPLUG_CPU
257 select IRQ_DOMAIN
258 select IRQ_FORCED_THREADING
259 select JUMP_LABEL
260 select KASAN_VMALLOC if KASAN
261 select LOCK_MM_AND_FIND_VMA
262 select MODULES_USE_ELF_RELA
263 select NEED_DMA_MAP_STATE
264 select NEED_SG_DMA_LENGTH
265 select OF
266 select OF_EARLY_FLATTREE
267 select PCI_DOMAINS_GENERIC if PCI
268 select PCI_ECAM if (ACPI && PCI)
269 select PCI_SYSCALL if PCI
270 select POWER_RESET
271 select POWER_SUPPLY
272 select SPARSE_IRQ
273 select SWIOTLB
274 select SYSCTL_EXCEPTION_TRACE
275 select THREAD_INFO_IN_TASK
276 select HAVE_ARCH_USERFAULTFD_MINOR if USERFAULTFD
277 select HAVE_ARCH_USERFAULTFD_WP if USERFAULTFD
278 select TRACE_IRQFLAGS_SUPPORT
279 select TRACE_IRQFLAGS_NMI_SUPPORT
280 select HAVE_SOFTIRQ_ON_OWN_STACK
281 select USER_STACKTRACE_SUPPORT
282 select VDSO_GETRANDOM
283 help
284 ARM 64-bit (AArch64) Linux support.
285
286config RUSTC_SUPPORTS_ARM64
287 def_bool y
288 depends on CPU_LITTLE_ENDIAN
289 # Shadow call stack is only supported on certain rustc versions.
290 #
291 # When using the UNWIND_PATCH_PAC_INTO_SCS option, rustc version 1.80+ is
292 # required due to use of the -Zfixed-x18 flag.
293 #
294 # Otherwise, rustc version 1.82+ is required due to use of the
295 # -Zsanitizer=shadow-call-stack flag.
296 depends on !SHADOW_CALL_STACK || RUSTC_VERSION >= 108200 || RUSTC_VERSION >= 108000 && UNWIND_PATCH_PAC_INTO_SCS
297
298config CLANG_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS
299 def_bool CC_IS_CLANG
300 # https://github.com/ClangBuiltLinux/linux/issues/1507
301 depends on AS_IS_GNU || (AS_IS_LLVM && (LD_IS_LLD || LD_VERSION >= 23600))
302
303config GCC_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS
304 def_bool CC_IS_GCC
305 depends on $(cc-option,-fpatchable-function-entry=2)
306
307config 64BIT
308 def_bool y
309
310config MMU
311 def_bool y
312
313config ARM64_CONT_PTE_SHIFT
314 int
315 default 5 if PAGE_SIZE_64KB
316 default 7 if PAGE_SIZE_16KB
317 default 4
318
319config ARM64_CONT_PMD_SHIFT
320 int
321 default 5 if PAGE_SIZE_64KB
322 default 5 if PAGE_SIZE_16KB
323 default 4
324
325config ARCH_MMAP_RND_BITS_MIN
326 default 14 if PAGE_SIZE_64KB
327 default 16 if PAGE_SIZE_16KB
328 default 18
329
330# max bits determined by the following formula:
331# VA_BITS - PTDESC_TABLE_SHIFT
332config ARCH_MMAP_RND_BITS_MAX
333 default 19 if ARM64_VA_BITS=36
334 default 24 if ARM64_VA_BITS=39
335 default 27 if ARM64_VA_BITS=42
336 default 30 if ARM64_VA_BITS=47
337 default 29 if (ARM64_VA_BITS=48 || ARM64_VA_BITS=52) && ARM64_64K_PAGES
338 default 31 if (ARM64_VA_BITS=48 || ARM64_VA_BITS=52) && ARM64_16K_PAGES
339 default 33 if (ARM64_VA_BITS=48 || ARM64_VA_BITS=52)
340 default 14 if ARM64_64K_PAGES
341 default 16 if ARM64_16K_PAGES
342 default 18
343
344config ARCH_MMAP_RND_COMPAT_BITS_MIN
345 default 7 if ARM64_64K_PAGES
346 default 9 if ARM64_16K_PAGES
347 default 11
348
349config ARCH_MMAP_RND_COMPAT_BITS_MAX
350 default 16
351
352config NO_IOPORT_MAP
353 def_bool y if !PCI
354
355config STACKTRACE_SUPPORT
356 def_bool y
357
358config ILLEGAL_POINTER_VALUE
359 hex
360 default 0xdead000000000000
361
362config LOCKDEP_SUPPORT
363 def_bool y
364
365config GENERIC_BUG
366 def_bool y
367 depends on BUG
368
369config GENERIC_BUG_RELATIVE_POINTERS
370 def_bool y
371 depends on GENERIC_BUG
372
373config GENERIC_HWEIGHT
374 def_bool y
375
376config GENERIC_CSUM
377 def_bool y
378
379config GENERIC_CALIBRATE_DELAY
380 def_bool y
381
382config SMP
383 def_bool y
384
385config KERNEL_MODE_NEON
386 def_bool y
387
388config FIX_EARLYCON_MEM
389 def_bool y
390
391config PGTABLE_LEVELS
392 int
393 default 2 if ARM64_16K_PAGES && ARM64_VA_BITS_36
394 default 2 if ARM64_64K_PAGES && ARM64_VA_BITS_42
395 default 3 if ARM64_64K_PAGES && (ARM64_VA_BITS_48 || ARM64_VA_BITS_52)
396 default 3 if ARM64_4K_PAGES && ARM64_VA_BITS_39
397 default 3 if ARM64_16K_PAGES && ARM64_VA_BITS_47
398 default 4 if ARM64_16K_PAGES && (ARM64_VA_BITS_48 || ARM64_VA_BITS_52)
399 default 4 if !ARM64_64K_PAGES && ARM64_VA_BITS_48
400 default 5 if ARM64_4K_PAGES && ARM64_VA_BITS_52
401
402config ARCH_SUPPORTS_UPROBES
403 def_bool y
404
405config ARCH_PROC_KCORE_TEXT
406 def_bool y
407
408config BROKEN_GAS_INST
409 def_bool !$(as-instr,1:\n.inst 0\n.rept . - 1b\n\nnop\n.endr\n)
410
411config BUILTIN_RETURN_ADDRESS_STRIPS_PAC
412 bool
413 # Clang's __builtin_return_address() strips the PAC since 12.0.0
414 # https://github.com/llvm/llvm-project/commit/2a96f47c5ffca84cd774ad402cacd137f4bf45e2
415 default y if CC_IS_CLANG
416 # GCC's __builtin_return_address() strips the PAC since 11.1.0,
417 # and this was backported to 10.2.0, 9.4.0, 8.5.0, but not earlier
418 # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94891
419 default y if CC_IS_GCC && (GCC_VERSION >= 110100)
420 default y if CC_IS_GCC && (GCC_VERSION >= 100200) && (GCC_VERSION < 110000)
421 default y if CC_IS_GCC && (GCC_VERSION >= 90400) && (GCC_VERSION < 100000)
422 default y if CC_IS_GCC && (GCC_VERSION >= 80500) && (GCC_VERSION < 90000)
423 default n
424
425config KASAN_SHADOW_OFFSET
426 hex
427 depends on KASAN_GENERIC || KASAN_SW_TAGS
428 default 0xdfff800000000000 if (ARM64_VA_BITS_48 || (ARM64_VA_BITS_52 && !ARM64_16K_PAGES)) && !KASAN_SW_TAGS
429 default 0xdfffc00000000000 if (ARM64_VA_BITS_47 || ARM64_VA_BITS_52) && ARM64_16K_PAGES && !KASAN_SW_TAGS
430 default 0xdffffe0000000000 if ARM64_VA_BITS_42 && !KASAN_SW_TAGS
431 default 0xdfffffc000000000 if ARM64_VA_BITS_39 && !KASAN_SW_TAGS
432 default 0xdffffff800000000 if ARM64_VA_BITS_36 && !KASAN_SW_TAGS
433 default 0xefff800000000000 if (ARM64_VA_BITS_48 || (ARM64_VA_BITS_52 && !ARM64_16K_PAGES)) && KASAN_SW_TAGS
434 default 0xefffc00000000000 if (ARM64_VA_BITS_47 || ARM64_VA_BITS_52) && ARM64_16K_PAGES && KASAN_SW_TAGS
435 default 0xeffffe0000000000 if ARM64_VA_BITS_42 && KASAN_SW_TAGS
436 default 0xefffffc000000000 if ARM64_VA_BITS_39 && KASAN_SW_TAGS
437 default 0xeffffff800000000 if ARM64_VA_BITS_36 && KASAN_SW_TAGS
438 default 0xffffffffffffffff
439
440config UNWIND_TABLES
441 bool
442
443source "arch/arm64/Kconfig.platforms"
444
445menu "Kernel Features"
446
447menu "ARM errata workarounds via the alternatives framework"
448
449config AMPERE_ERRATUM_AC03_CPU_38
450 bool "AmpereOne: AC03_CPU_38: Certain bits in the Virtualization Translation Control Register and Translation Control Registers do not follow RES0 semantics"
451 default y
452 help
453 This option adds an alternative code sequence to work around Ampere
454 errata AC03_CPU_38 and AC04_CPU_10 on AmpereOne.
455
456 The affected design reports FEAT_HAFDBS as not implemented in
457 ID_AA64MMFR1_EL1.HAFDBS, but (V)TCR_ELx.{HA,HD} are not RES0
458 as required by the architecture. The unadvertised HAFDBS
459 implementation suffers from an additional erratum where hardware
460 A/D updates can occur after a PTE has been marked invalid.
461
462 The workaround forces KVM to explicitly set VTCR_EL2.HA to 0,
463 which avoids enabling unadvertised hardware Access Flag management
464 at stage-2.
465
466 If unsure, say Y.
467
468config AMPERE_ERRATUM_AC04_CPU_23
469 bool "AmpereOne: AC04_CPU_23: Failure to synchronize writes to HCR_EL2 may corrupt address translations."
470 default y
471 help
472 This option adds an alternative code sequence to work around Ampere
473 errata AC04_CPU_23 on AmpereOne.
474
475 Updates to HCR_EL2 can rarely corrupt simultaneous translations for
476 data addresses initiated by load/store instructions. Only
477 instruction initiated translations are vulnerable, not translations
478 from prefetches for example. A DSB before the store to HCR_EL2 is
479 sufficient to prevent older instructions from hitting the window
480 for corruption, and an ISB after is sufficient to prevent younger
481 instructions from hitting the window for corruption.
482
483 If unsure, say Y.
484
485config ARM64_WORKAROUND_CLEAN_CACHE
486 bool
487
488config ARM64_ERRATUM_826319
489 bool "Cortex-A53: 826319: System might deadlock if a write cannot complete until read data is accepted"
490 default y
491 select ARM64_WORKAROUND_CLEAN_CACHE
492 help
493 This option adds an alternative code sequence to work around ARM
494 erratum 826319 on Cortex-A53 parts up to r0p2 with an AMBA 4 ACE or
495 AXI master interface and an L2 cache.
496
497 If a Cortex-A53 uses an AMBA AXI4 ACE interface to other processors
498 and is unable to accept a certain write via this interface, it will
499 not progress on read data presented on the read data channel and the
500 system can deadlock.
501
502 The workaround promotes data cache clean instructions to
503 data cache clean-and-invalidate.
504 Please note that this does not necessarily enable the workaround,
505 as it depends on the alternative framework, which will only patch
506 the kernel if an affected CPU is detected.
507
508 If unsure, say Y.
509
510config ARM64_ERRATUM_827319
511 bool "Cortex-A53: 827319: Data cache clean instructions might cause overlapping transactions to the interconnect"
512 default y
513 select ARM64_WORKAROUND_CLEAN_CACHE
514 help
515 This option adds an alternative code sequence to work around ARM
516 erratum 827319 on Cortex-A53 parts up to r0p2 with an AMBA 5 CHI
517 master interface and an L2 cache.
518
519 Under certain conditions this erratum can cause a clean line eviction
520 to occur at the same time as another transaction to the same address
521 on the AMBA 5 CHI interface, which can cause data corruption if the
522 interconnect reorders the two transactions.
523
524 The workaround promotes data cache clean instructions to
525 data cache clean-and-invalidate.
526 Please note that this does not necessarily enable the workaround,
527 as it depends on the alternative framework, which will only patch
528 the kernel if an affected CPU is detected.
529
530 If unsure, say Y.
531
532config ARM64_ERRATUM_824069
533 bool "Cortex-A53: 824069: Cache line might not be marked as clean after a CleanShared snoop"
534 default y
535 select ARM64_WORKAROUND_CLEAN_CACHE
536 help
537 This option adds an alternative code sequence to work around ARM
538 erratum 824069 on Cortex-A53 parts up to r0p2 when it is connected
539 to a coherent interconnect.
540
541 If a Cortex-A53 processor is executing a store or prefetch for
542 write instruction at the same time as a processor in another
543 cluster is executing a cache maintenance operation to the same
544 address, then this erratum might cause a clean cache line to be
545 incorrectly marked as dirty.
546
547 The workaround promotes data cache clean instructions to
548 data cache clean-and-invalidate.
549 Please note that this option does not necessarily enable the
550 workaround, as it depends on the alternative framework, which will
551 only patch the kernel if an affected CPU is detected.
552
553 If unsure, say Y.
554
555config ARM64_ERRATUM_819472
556 bool "Cortex-A53: 819472: Store exclusive instructions might cause data corruption"
557 default y
558 select ARM64_WORKAROUND_CLEAN_CACHE
559 help
560 This option adds an alternative code sequence to work around ARM
561 erratum 819472 on Cortex-A53 parts up to r0p1 with an L2 cache
562 present when it is connected to a coherent interconnect.
563
564 If the processor is executing a load and store exclusive sequence at
565 the same time as a processor in another cluster is executing a cache
566 maintenance operation to the same address, then this erratum might
567 cause data corruption.
568
569 The workaround promotes data cache clean instructions to
570 data cache clean-and-invalidate.
571 Please note that this does not necessarily enable the workaround,
572 as it depends on the alternative framework, which will only patch
573 the kernel if an affected CPU is detected.
574
575 If unsure, say Y.
576
577config ARM64_ERRATUM_832075
578 bool "Cortex-A57: 832075: possible deadlock on mixing exclusive memory accesses with device loads"
579 default y
580 help
581 This option adds an alternative code sequence to work around ARM
582 erratum 832075 on Cortex-A57 parts up to r1p2.
583
584 Affected Cortex-A57 parts might deadlock when exclusive load/store
585 instructions to Write-Back memory are mixed with Device loads.
586
587 The workaround is to promote device loads to use Load-Acquire
588 semantics.
589 Please note that this does not necessarily enable the workaround,
590 as it depends on the alternative framework, which will only patch
591 the kernel if an affected CPU is detected.
592
593 If unsure, say Y.
594
595config ARM64_ERRATUM_834220
596 bool "Cortex-A57: 834220: Stage 2 translation fault might be incorrectly reported in presence of a Stage 1 fault (rare)"
597 depends on KVM
598 help
599 This option adds an alternative code sequence to work around ARM
600 erratum 834220 on Cortex-A57 parts up to r1p2.
601
602 Affected Cortex-A57 parts might report a Stage 2 translation
603 fault as the result of a Stage 1 fault for load crossing a
604 page boundary when there is a permission or device memory
605 alignment fault at Stage 1 and a translation fault at Stage 2.
606
607 The workaround is to verify that the Stage 1 translation
608 doesn't generate a fault before handling the Stage 2 fault.
609 Please note that this does not necessarily enable the workaround,
610 as it depends on the alternative framework, which will only patch
611 the kernel if an affected CPU is detected.
612
613 If unsure, say N.
614
615config ARM64_ERRATUM_1742098
616 bool "Cortex-A57/A72: 1742098: ELR recorded incorrectly on interrupt taken between cryptographic instructions in a sequence"
617 depends on COMPAT
618 default y
619 help
620 This option removes the AES hwcap for aarch32 user-space to
621 workaround erratum 1742098 on Cortex-A57 and Cortex-A72.
622
623 Affected parts may corrupt the AES state if an interrupt is
624 taken between a pair of AES instructions. These instructions
625 are only present if the cryptography extensions are present.
626 All software should have a fallback implementation for CPUs
627 that don't implement the cryptography extensions.
628
629 If unsure, say Y.
630
631config ARM64_ERRATUM_845719
632 bool "Cortex-A53: 845719: a load might read incorrect data"
633 depends on COMPAT
634 default y
635 help
636 This option adds an alternative code sequence to work around ARM
637 erratum 845719 on Cortex-A53 parts up to r0p4.
638
639 When running a compat (AArch32) userspace on an affected Cortex-A53
640 part, a load at EL0 from a virtual address that matches the bottom 32
641 bits of the virtual address used by a recent load at (AArch64) EL1
642 might return incorrect data.
643
644 The workaround is to write the contextidr_el1 register on exception
645 return to a 32-bit task.
646 Please note that this does not necessarily enable the workaround,
647 as it depends on the alternative framework, which will only patch
648 the kernel if an affected CPU is detected.
649
650 If unsure, say Y.
651
652config ARM64_ERRATUM_843419
653 bool "Cortex-A53: 843419: A load or store might access an incorrect address"
654 default y
655 help
656 This option links the kernel with '--fix-cortex-a53-843419' and
657 enables PLT support to replace certain ADRP instructions, which can
658 cause subsequent memory accesses to use an incorrect address on
659 Cortex-A53 parts up to r0p4.
660
661 If unsure, say Y.
662
663config ARM64_ERRATUM_1024718
664 bool "Cortex-A55: 1024718: Update of DBM/AP bits without break before make might result in incorrect update"
665 default y
666 help
667 This option adds a workaround for ARM Cortex-A55 Erratum 1024718.
668
669 Affected Cortex-A55 cores (all revisions) could cause incorrect
670 update of the hardware dirty bit when the DBM/AP bits are updated
671 without a break-before-make. The workaround is to disable the usage
672 of hardware DBM locally on the affected cores. CPUs not affected by
673 this erratum will continue to use the feature.
674
675 If unsure, say Y.
676
677config ARM64_ERRATUM_1418040
678 bool "Cortex-A76/Neoverse-N1: MRC read following MRRC read of specific Generic Timer in AArch32 might give incorrect result"
679 default y
680 depends on COMPAT
681 help
682 This option adds a workaround for ARM Cortex-A76/Neoverse-N1
683 errata 1188873 and 1418040.
684
685 Affected Cortex-A76/Neoverse-N1 cores (r0p0 to r3p1) could
686 cause register corruption when accessing the timer registers
687 from AArch32 userspace.
688
689 If unsure, say Y.
690
691config ARM64_WORKAROUND_SPECULATIVE_AT
692 bool
693
694config ARM64_ERRATUM_1165522
695 bool "Cortex-A76: 1165522: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
696 default y
697 select ARM64_WORKAROUND_SPECULATIVE_AT
698 help
699 This option adds a workaround for ARM Cortex-A76 erratum 1165522.
700
701 Affected Cortex-A76 cores (r0p0, r1p0, r2p0) could end-up with
702 corrupted TLBs by speculating an AT instruction during a guest
703 context switch.
704
705 If unsure, say Y.
706
707config ARM64_ERRATUM_1319367
708 bool "Cortex-A57/A72: 1319537: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
709 default y
710 select ARM64_WORKAROUND_SPECULATIVE_AT
711 help
712 This option adds work arounds for ARM Cortex-A57 erratum 1319537
713 and A72 erratum 1319367
714
715 Cortex-A57 and A72 cores could end-up with corrupted TLBs by
716 speculating an AT instruction during a guest context switch.
717
718 If unsure, say Y.
719
720config ARM64_ERRATUM_1530923
721 bool "Cortex-A55: 1530923: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
722 default y
723 select ARM64_WORKAROUND_SPECULATIVE_AT
724 help
725 This option adds a workaround for ARM Cortex-A55 erratum 1530923.
726
727 Affected Cortex-A55 cores (r0p0, r0p1, r1p0, r2p0) could end-up with
728 corrupted TLBs by speculating an AT instruction during a guest
729 context switch.
730
731 If unsure, say Y.
732
733config ARM64_WORKAROUND_REPEAT_TLBI
734 bool
735
736config ARM64_ERRATUM_2441007
737 bool "Cortex-A55: Completion of affected memory accesses might not be guaranteed by completion of a TLBI (rare)"
738 select ARM64_WORKAROUND_REPEAT_TLBI
739 help
740 This option adds a workaround for ARM Cortex-A55 erratum #2441007.
741
742 Under very rare circumstances, affected Cortex-A55 CPUs
743 may not handle a race between a break-before-make sequence on one
744 CPU, and another CPU accessing the same page. This could allow a
745 store to a page that has been unmapped.
746
747 Work around this by adding the affected CPUs to the list that needs
748 TLB sequences to be done twice.
749
750 If unsure, say N.
751
752config ARM64_ERRATUM_1286807
753 bool "Cortex-A76: Modification of the translation table for a virtual address might lead to read-after-read ordering violation (rare)"
754 select ARM64_WORKAROUND_REPEAT_TLBI
755 help
756 This option adds a workaround for ARM Cortex-A76 erratum 1286807.
757
758 On the affected Cortex-A76 cores (r0p0 to r3p0), if a virtual
759 address for a cacheable mapping of a location is being
760 accessed by a core while another core is remapping the virtual
761 address to a new physical page using the recommended
762 break-before-make sequence, then under very rare circumstances
763 TLBI+DSB completes before a read using the translation being
764 invalidated has been observed by other observers. The
765 workaround repeats the TLBI+DSB operation.
766
767 If unsure, say N.
768
769config ARM64_ERRATUM_1463225
770 bool "Cortex-A76: Software Step might prevent interrupt recognition"
771 default y
772 help
773 This option adds a workaround for Arm Cortex-A76 erratum 1463225.
774
775 On the affected Cortex-A76 cores (r0p0 to r3p1), software stepping
776 of a system call instruction (SVC) can prevent recognition of
777 subsequent interrupts when software stepping is disabled in the
778 exception handler of the system call and either kernel debugging
779 is enabled or VHE is in use.
780
781 Work around the erratum by triggering a dummy step exception
782 when handling a system call from a task that is being stepped
783 in a VHE configuration of the kernel.
784
785 If unsure, say Y.
786
787config ARM64_ERRATUM_1542419
788 bool "Neoverse-N1: workaround mis-ordering of instruction fetches (rare)"
789 help
790 This option adds a workaround for ARM Neoverse-N1 erratum
791 1542419.
792
793 Affected Neoverse-N1 cores could execute a stale instruction when
794 modified by another CPU. The workaround depends on a firmware
795 counterpart.
796
797 Workaround the issue by hiding the DIC feature from EL0. This
798 forces user-space to perform cache maintenance.
799
800 If unsure, say N.
801
802config ARM64_ERRATUM_1508412
803 bool "Cortex-A77: 1508412: workaround deadlock on sequence of NC/Device load and store exclusive or PAR read"
804 default y
805 help
806 This option adds a workaround for Arm Cortex-A77 erratum 1508412.
807
808 Affected Cortex-A77 cores (r0p0, r1p0) could deadlock on a sequence
809 of a store-exclusive or read of PAR_EL1 and a load with device or
810 non-cacheable memory attributes. The workaround depends on a firmware
811 counterpart.
812
813 KVM guests must also have the workaround implemented or they can
814 deadlock the system.
815
816 Work around the issue by inserting DMB SY barriers around PAR_EL1
817 register reads and warning KVM users. The DMB barrier is sufficient
818 to prevent a speculative PAR_EL1 read.
819
820 If unsure, say Y.
821
822config ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
823 bool
824
825config ARM64_ERRATUM_2051678
826 bool "Cortex-A510: 2051678: disable Hardware Update of the page table dirty bit"
827 default y
828 help
829 This options adds the workaround for ARM Cortex-A510 erratum ARM64_ERRATUM_2051678.
830 Affected Cortex-A510 might not respect the ordering rules for
831 hardware update of the page table's dirty bit. The workaround
832 is to not enable the feature on affected CPUs.
833
834 If unsure, say Y.
835
836config ARM64_ERRATUM_2077057
837 bool "Cortex-A510: 2077057: workaround software-step corrupting SPSR_EL2"
838 default y
839 help
840 This option adds the workaround for ARM Cortex-A510 erratum 2077057.
841 Affected Cortex-A510 may corrupt SPSR_EL2 when the a step exception is
842 expected, but a Pointer Authentication trap is taken instead. The
843 erratum causes SPSR_EL1 to be copied to SPSR_EL2, which could allow
844 EL1 to cause a return to EL2 with a guest controlled ELR_EL2.
845
846 This can only happen when EL2 is stepping EL1.
847
848 When these conditions occur, the SPSR_EL2 value is unchanged from the
849 previous guest entry, and can be restored from the in-memory copy.
850
851 If unsure, say Y.
852
853config ARM64_ERRATUM_2658417
854 bool "Cortex-A510: 2658417: remove BF16 support due to incorrect result"
855 default y
856 help
857 This option adds the workaround for ARM Cortex-A510 erratum 2658417.
858 Affected Cortex-A510 (r0p0 to r1p1) may produce the wrong result for
859 BFMMLA or VMMLA instructions in rare circumstances when a pair of
860 A510 CPUs are using shared neon hardware. As the sharing is not
861 discoverable by the kernel, hide the BF16 HWCAP to indicate that
862 user-space should not be using these instructions.
863
864 If unsure, say Y.
865
866config ARM64_ERRATUM_2119858
867 bool "Cortex-A710/X2: 2119858: workaround TRBE overwriting trace data in FILL mode"
868 default y
869 depends on CORESIGHT_TRBE
870 select ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
871 help
872 This option adds the workaround for ARM Cortex-A710/X2 erratum 2119858.
873
874 Affected Cortex-A710/X2 cores could overwrite up to 3 cache lines of trace
875 data at the base of the buffer (pointed to by TRBASER_EL1) in FILL mode in
876 the event of a WRAP event.
877
878 Work around the issue by always making sure we move the TRBPTR_EL1 by
879 256 bytes before enabling the buffer and filling the first 256 bytes of
880 the buffer with ETM ignore packets upon disabling.
881
882 If unsure, say Y.
883
884config ARM64_ERRATUM_2139208
885 bool "Neoverse-N2: 2139208: workaround TRBE overwriting trace data in FILL mode"
886 default y
887 depends on CORESIGHT_TRBE
888 select ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
889 help
890 This option adds the workaround for ARM Neoverse-N2 erratum 2139208.
891
892 Affected Neoverse-N2 cores could overwrite up to 3 cache lines of trace
893 data at the base of the buffer (pointed to by TRBASER_EL1) in FILL mode in
894 the event of a WRAP event.
895
896 Work around the issue by always making sure we move the TRBPTR_EL1 by
897 256 bytes before enabling the buffer and filling the first 256 bytes of
898 the buffer with ETM ignore packets upon disabling.
899
900 If unsure, say Y.
901
902config ARM64_WORKAROUND_TSB_FLUSH_FAILURE
903 bool
904
905config ARM64_ERRATUM_2054223
906 bool "Cortex-A710: 2054223: workaround TSB instruction failing to flush trace"
907 default y
908 select ARM64_WORKAROUND_TSB_FLUSH_FAILURE
909 help
910 Enable workaround for ARM Cortex-A710 erratum 2054223
911
912 Affected cores may fail to flush the trace data on a TSB instruction, when
913 the PE is in trace prohibited state. This will cause losing a few bytes
914 of the trace cached.
915
916 Workaround is to issue two TSB consecutively on affected cores.
917
918 If unsure, say Y.
919
920config ARM64_ERRATUM_2067961
921 bool "Neoverse-N2: 2067961: workaround TSB instruction failing to flush trace"
922 default y
923 select ARM64_WORKAROUND_TSB_FLUSH_FAILURE
924 help
925 Enable workaround for ARM Neoverse-N2 erratum 2067961
926
927 Affected cores may fail to flush the trace data on a TSB instruction, when
928 the PE is in trace prohibited state. This will cause losing a few bytes
929 of the trace cached.
930
931 Workaround is to issue two TSB consecutively on affected cores.
932
933 If unsure, say Y.
934
935config ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE
936 bool
937
938config ARM64_ERRATUM_2253138
939 bool "Neoverse-N2: 2253138: workaround TRBE writing to address out-of-range"
940 depends on CORESIGHT_TRBE
941 default y
942 select ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE
943 help
944 This option adds the workaround for ARM Neoverse-N2 erratum 2253138.
945
946 Affected Neoverse-N2 cores might write to an out-of-range address, not reserved
947 for TRBE. Under some conditions, the TRBE might generate a write to the next
948 virtually addressed page following the last page of the TRBE address space
949 (i.e., the TRBLIMITR_EL1.LIMIT), instead of wrapping around to the base.
950
951 Work around this in the driver by always making sure that there is a
952 page beyond the TRBLIMITR_EL1.LIMIT, within the space allowed for the TRBE.
953
954 If unsure, say Y.
955
956config ARM64_ERRATUM_2224489
957 bool "Cortex-A710/X2: 2224489: workaround TRBE writing to address out-of-range"
958 depends on CORESIGHT_TRBE
959 default y
960 select ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE
961 help
962 This option adds the workaround for ARM Cortex-A710/X2 erratum 2224489.
963
964 Affected Cortex-A710/X2 cores might write to an out-of-range address, not reserved
965 for TRBE. Under some conditions, the TRBE might generate a write to the next
966 virtually addressed page following the last page of the TRBE address space
967 (i.e., the TRBLIMITR_EL1.LIMIT), instead of wrapping around to the base.
968
969 Work around this in the driver by always making sure that there is a
970 page beyond the TRBLIMITR_EL1.LIMIT, within the space allowed for the TRBE.
971
972 If unsure, say Y.
973
974config ARM64_ERRATUM_2441009
975 bool "Cortex-A510: Completion of affected memory accesses might not be guaranteed by completion of a TLBI (rare)"
976 select ARM64_WORKAROUND_REPEAT_TLBI
977 help
978 This option adds a workaround for ARM Cortex-A510 erratum #2441009.
979
980 Under very rare circumstances, affected Cortex-A510 CPUs
981 may not handle a race between a break-before-make sequence on one
982 CPU, and another CPU accessing the same page. This could allow a
983 store to a page that has been unmapped.
984
985 Work around this by adding the affected CPUs to the list that needs
986 TLB sequences to be done twice.
987
988 If unsure, say N.
989
990config ARM64_ERRATUM_2064142
991 bool "Cortex-A510: 2064142: workaround TRBE register writes while disabled"
992 depends on CORESIGHT_TRBE
993 default y
994 help
995 This option adds the workaround for ARM Cortex-A510 erratum 2064142.
996
997 Affected Cortex-A510 core might fail to write into system registers after the
998 TRBE has been disabled. Under some conditions after the TRBE has been disabled
999 writes into TRBE registers TRBLIMITR_EL1, TRBPTR_EL1, TRBBASER_EL1, TRBSR_EL1,
1000 and TRBTRG_EL1 will be ignored and will not be effected.
1001
1002 Work around this in the driver by executing TSB CSYNC and DSB after collection
1003 is stopped and before performing a system register write to one of the affected
1004 registers.
1005
1006 If unsure, say Y.
1007
1008config ARM64_ERRATUM_2038923
1009 bool "Cortex-A510: 2038923: workaround TRBE corruption with enable"
1010 depends on CORESIGHT_TRBE
1011 default y
1012 help
1013 This option adds the workaround for ARM Cortex-A510 erratum 2038923.
1014
1015 Affected Cortex-A510 core might cause an inconsistent view on whether trace is
1016 prohibited within the CPU. As a result, the trace buffer or trace buffer state
1017 might be corrupted. This happens after TRBE buffer has been enabled by setting
1018 TRBLIMITR_EL1.E, followed by just a single context synchronization event before
1019 execution changes from a context, in which trace is prohibited to one where it
1020 isn't, or vice versa. In these mentioned conditions, the view of whether trace
1021 is prohibited is inconsistent between parts of the CPU, and the trace buffer or
1022 the trace buffer state might be corrupted.
1023
1024 Work around this in the driver by preventing an inconsistent view of whether the
1025 trace is prohibited or not based on TRBLIMITR_EL1.E by immediately following a
1026 change to TRBLIMITR_EL1.E with at least one ISB instruction before an ERET, or
1027 two ISB instructions if no ERET is to take place.
1028
1029 If unsure, say Y.
1030
1031config ARM64_ERRATUM_1902691
1032 bool "Cortex-A510: 1902691: workaround TRBE trace corruption"
1033 depends on CORESIGHT_TRBE
1034 default y
1035 help
1036 This option adds the workaround for ARM Cortex-A510 erratum 1902691.
1037
1038 Affected Cortex-A510 core might cause trace data corruption, when being written
1039 into the memory. Effectively TRBE is broken and hence cannot be used to capture
1040 trace data.
1041
1042 Work around this problem in the driver by just preventing TRBE initialization on
1043 affected cpus. The firmware must have disabled the access to TRBE for the kernel
1044 on such implementations. This will cover the kernel for any firmware that doesn't
1045 do this already.
1046
1047 If unsure, say Y.
1048
1049config ARM64_ERRATUM_2457168
1050 bool "Cortex-A510: 2457168: workaround for AMEVCNTR01 incrementing incorrectly"
1051 depends on ARM64_AMU_EXTN
1052 default y
1053 help
1054 This option adds the workaround for ARM Cortex-A510 erratum 2457168.
1055
1056 The AMU counter AMEVCNTR01 (constant counter) should increment at the same rate
1057 as the system counter. On affected Cortex-A510 cores AMEVCNTR01 increments
1058 incorrectly giving a significantly higher output value.
1059
1060 Work around this problem by returning 0 when reading the affected counter in
1061 key locations that results in disabling all users of this counter. This effect
1062 is the same to firmware disabling affected counters.
1063
1064 If unsure, say Y.
1065
1066config ARM64_ERRATUM_2645198
1067 bool "Cortex-A715: 2645198: Workaround possible [ESR|FAR]_ELx corruption"
1068 default y
1069 help
1070 This option adds the workaround for ARM Cortex-A715 erratum 2645198.
1071
1072 If a Cortex-A715 cpu sees a page mapping permissions change from executable
1073 to non-executable, it may corrupt the ESR_ELx and FAR_ELx registers on the
1074 next instruction abort caused by permission fault.
1075
1076 Only user-space does executable to non-executable permission transition via
1077 mprotect() system call. Workaround the problem by doing a break-before-make
1078 TLB invalidation, for all changes to executable user space mappings.
1079
1080 If unsure, say Y.
1081
1082config ARM64_WORKAROUND_SPECULATIVE_UNPRIV_LOAD
1083 bool
1084
1085config ARM64_ERRATUM_2966298
1086 bool "Cortex-A520: 2966298: workaround for speculatively executed unprivileged load"
1087 select ARM64_WORKAROUND_SPECULATIVE_UNPRIV_LOAD
1088 default y
1089 help
1090 This option adds the workaround for ARM Cortex-A520 erratum 2966298.
1091
1092 On an affected Cortex-A520 core, a speculatively executed unprivileged
1093 load might leak data from a privileged level via a cache side channel.
1094
1095 Work around this problem by executing a TLBI before returning to EL0.
1096
1097 If unsure, say Y.
1098
1099config ARM64_ERRATUM_3117295
1100 bool "Cortex-A510: 3117295: workaround for speculatively executed unprivileged load"
1101 select ARM64_WORKAROUND_SPECULATIVE_UNPRIV_LOAD
1102 default y
1103 help
1104 This option adds the workaround for ARM Cortex-A510 erratum 3117295.
1105
1106 On an affected Cortex-A510 core, a speculatively executed unprivileged
1107 load might leak data from a privileged level via a cache side channel.
1108
1109 Work around this problem by executing a TLBI before returning to EL0.
1110
1111 If unsure, say Y.
1112
1113config ARM64_ERRATUM_3194386
1114 bool "Cortex-*/Neoverse-*: workaround for MSR SSBS not self-synchronizing"
1115 default y
1116 help
1117 This option adds the workaround for the following errata:
1118
1119 * ARM Cortex-A76 erratum 3324349
1120 * ARM Cortex-A77 erratum 3324348
1121 * ARM Cortex-A78 erratum 3324344
1122 * ARM Cortex-A78C erratum 3324346
1123 * ARM Cortex-A78C erratum 3324347
1124 * ARM Cortex-A710 erratam 3324338
1125 * ARM Cortex-A715 errartum 3456084
1126 * ARM Cortex-A720 erratum 3456091
1127 * ARM Cortex-A725 erratum 3456106
1128 * ARM Cortex-X1 erratum 3324344
1129 * ARM Cortex-X1C erratum 3324346
1130 * ARM Cortex-X2 erratum 3324338
1131 * ARM Cortex-X3 erratum 3324335
1132 * ARM Cortex-X4 erratum 3194386
1133 * ARM Cortex-X925 erratum 3324334
1134 * ARM Neoverse-N1 erratum 3324349
1135 * ARM Neoverse N2 erratum 3324339
1136 * ARM Neoverse-N3 erratum 3456111
1137 * ARM Neoverse-V1 erratum 3324341
1138 * ARM Neoverse V2 erratum 3324336
1139 * ARM Neoverse-V3 erratum 3312417
1140
1141 On affected cores "MSR SSBS, #0" instructions may not affect
1142 subsequent speculative instructions, which may permit unexepected
1143 speculative store bypassing.
1144
1145 Work around this problem by placing a Speculation Barrier (SB) or
1146 Instruction Synchronization Barrier (ISB) after kernel changes to
1147 SSBS. The presence of the SSBS special-purpose register is hidden
1148 from hwcaps and EL0 reads of ID_AA64PFR1_EL1, such that userspace
1149 will use the PR_SPEC_STORE_BYPASS prctl to change SSBS.
1150
1151 If unsure, say Y.
1152
1153config CAVIUM_ERRATUM_22375
1154 bool "Cavium erratum 22375, 24313"
1155 default y
1156 help
1157 Enable workaround for errata 22375 and 24313.
1158
1159 This implements two gicv3-its errata workarounds for ThunderX. Both
1160 with a small impact affecting only ITS table allocation.
1161
1162 erratum 22375: only alloc 8MB table size
1163 erratum 24313: ignore memory access type
1164
1165 The fixes are in ITS initialization and basically ignore memory access
1166 type and table size provided by the TYPER and BASER registers.
1167
1168 If unsure, say Y.
1169
1170config CAVIUM_ERRATUM_23144
1171 bool "Cavium erratum 23144: ITS SYNC hang on dual socket system"
1172 depends on NUMA
1173 default y
1174 help
1175 ITS SYNC command hang for cross node io and collections/cpu mapping.
1176
1177 If unsure, say Y.
1178
1179config CAVIUM_ERRATUM_23154
1180 bool "Cavium errata 23154 and 38545: GICv3 lacks HW synchronisation"
1181 default y
1182 help
1183 The ThunderX GICv3 implementation requires a modified version for
1184 reading the IAR status to ensure data synchronization
1185 (access to icc_iar1_el1 is not sync'ed before and after).
1186
1187 It also suffers from erratum 38545 (also present on Marvell's
1188 OcteonTX and OcteonTX2), resulting in deactivated interrupts being
1189 spuriously presented to the CPU interface.
1190
1191 If unsure, say Y.
1192
1193config CAVIUM_ERRATUM_27456
1194 bool "Cavium erratum 27456: Broadcast TLBI instructions may cause icache corruption"
1195 default y
1196 help
1197 On ThunderX T88 pass 1.x through 2.1 parts, broadcast TLBI
1198 instructions may cause the icache to become corrupted if it
1199 contains data for a non-current ASID. The fix is to
1200 invalidate the icache when changing the mm context.
1201
1202 If unsure, say Y.
1203
1204config CAVIUM_ERRATUM_30115
1205 bool "Cavium erratum 30115: Guest may disable interrupts in host"
1206 default y
1207 help
1208 On ThunderX T88 pass 1.x through 2.2, T81 pass 1.0 through
1209 1.2, and T83 Pass 1.0, KVM guest execution may disable
1210 interrupts in host. Trapping both GICv3 group-0 and group-1
1211 accesses sidesteps the issue.
1212
1213 If unsure, say Y.
1214
1215config CAVIUM_TX2_ERRATUM_219
1216 bool "Cavium ThunderX2 erratum 219: PRFM between TTBR change and ISB fails"
1217 default y
1218 help
1219 On Cavium ThunderX2, a load, store or prefetch instruction between a
1220 TTBR update and the corresponding context synchronizing operation can
1221 cause a spurious Data Abort to be delivered to any hardware thread in
1222 the CPU core.
1223
1224 Work around the issue by avoiding the problematic code sequence and
1225 trapping KVM guest TTBRx_EL1 writes to EL2 when SMT is enabled. The
1226 trap handler performs the corresponding register access, skips the
1227 instruction and ensures context synchronization by virtue of the
1228 exception return.
1229
1230 If unsure, say Y.
1231
1232config FUJITSU_ERRATUM_010001
1233 bool "Fujitsu-A64FX erratum E#010001: Undefined fault may occur wrongly"
1234 default y
1235 help
1236 This option adds a workaround for Fujitsu-A64FX erratum E#010001.
1237 On some variants of the Fujitsu-A64FX cores ver(1.0, 1.1), memory
1238 accesses may cause undefined fault (Data abort, DFSC=0b111111).
1239 This fault occurs under a specific hardware condition when a
1240 load/store instruction performs an address translation using:
1241 case-1 TTBR0_EL1 with TCR_EL1.NFD0 == 1.
1242 case-2 TTBR0_EL2 with TCR_EL2.NFD0 == 1.
1243 case-3 TTBR1_EL1 with TCR_EL1.NFD1 == 1.
1244 case-4 TTBR1_EL2 with TCR_EL2.NFD1 == 1.
1245
1246 The workaround is to ensure these bits are clear in TCR_ELx.
1247 The workaround only affects the Fujitsu-A64FX.
1248
1249 If unsure, say Y.
1250
1251config HISILICON_ERRATUM_161600802
1252 bool "Hip07 161600802: Erroneous redistributor VLPI base"
1253 default y
1254 help
1255 The HiSilicon Hip07 SoC uses the wrong redistributor base
1256 when issued ITS commands such as VMOVP and VMAPP, and requires
1257 a 128kB offset to be applied to the target address in this commands.
1258
1259 If unsure, say Y.
1260
1261config HISILICON_ERRATUM_162100801
1262 bool "Hip09 162100801 erratum support"
1263 default y
1264 help
1265 When enabling GICv4.1 in hip09, VMAPP will fail to clear some caches
1266 during unmapping operation, which will cause some vSGIs lost.
1267 To fix the issue, invalidate related vPE cache through GICR_INVALLR
1268 after VMOVP.
1269
1270 If unsure, say Y.
1271
1272config QCOM_FALKOR_ERRATUM_1003
1273 bool "Falkor E1003: Incorrect translation due to ASID change"
1274 default y
1275 help
1276 On Falkor v1, an incorrect ASID may be cached in the TLB when ASID
1277 and BADDR are changed together in TTBRx_EL1. Since we keep the ASID
1278 in TTBR1_EL1, this situation only occurs in the entry trampoline and
1279 then only for entries in the walk cache, since the leaf translation
1280 is unchanged. Work around the erratum by invalidating the walk cache
1281 entries for the trampoline before entering the kernel proper.
1282
1283config QCOM_FALKOR_ERRATUM_1009
1284 bool "Falkor E1009: Prematurely complete a DSB after a TLBI"
1285 default y
1286 select ARM64_WORKAROUND_REPEAT_TLBI
1287 help
1288 On Falkor v1, the CPU may prematurely complete a DSB following a
1289 TLBI xxIS invalidate maintenance operation. Repeat the TLBI operation
1290 one more time to fix the issue.
1291
1292 If unsure, say Y.
1293
1294config QCOM_QDF2400_ERRATUM_0065
1295 bool "QDF2400 E0065: Incorrect GITS_TYPER.ITT_Entry_size"
1296 default y
1297 help
1298 On Qualcomm Datacenter Technologies QDF2400 SoC, ITS hardware reports
1299 ITE size incorrectly. The GITS_TYPER.ITT_Entry_size field should have
1300 been indicated as 16Bytes (0xf), not 8Bytes (0x7).
1301
1302 If unsure, say Y.
1303
1304config QCOM_FALKOR_ERRATUM_E1041
1305 bool "Falkor E1041: Speculative instruction fetches might cause errant memory access"
1306 default y
1307 help
1308 Falkor CPU may speculatively fetch instructions from an improper
1309 memory location when MMU translation is changed from SCTLR_ELn[M]=1
1310 to SCTLR_ELn[M]=0. Prefix an ISB instruction to fix the problem.
1311
1312 If unsure, say Y.
1313
1314config NVIDIA_CARMEL_CNP_ERRATUM
1315 bool "NVIDIA Carmel CNP: CNP on Carmel semantically different than ARM cores"
1316 default y
1317 help
1318 If CNP is enabled on Carmel cores, non-sharable TLBIs on a core will not
1319 invalidate shared TLB entries installed by a different core, as it would
1320 on standard ARM cores.
1321
1322 If unsure, say Y.
1323
1324config ROCKCHIP_ERRATUM_3568002
1325 bool "Rockchip 3568002: GIC600 can not access physical addresses higher than 4GB"
1326 default y
1327 help
1328 The Rockchip RK3566 and RK3568 GIC600 SoC integrations have AXI
1329 addressing limited to the first 32bit of physical address space.
1330
1331 If unsure, say Y.
1332
1333config ROCKCHIP_ERRATUM_3588001
1334 bool "Rockchip 3588001: GIC600 can not support shareability attributes"
1335 default y
1336 help
1337 The Rockchip RK3588 GIC600 SoC integration does not support ACE/ACE-lite.
1338 This means, that its sharability feature may not be used, even though it
1339 is supported by the IP itself.
1340
1341 If unsure, say Y.
1342
1343config SOCIONEXT_SYNQUACER_PREITS
1344 bool "Socionext Synquacer: Workaround for GICv3 pre-ITS"
1345 default y
1346 help
1347 Socionext Synquacer SoCs implement a separate h/w block to generate
1348 MSI doorbell writes with non-zero values for the device ID.
1349
1350 If unsure, say Y.
1351
1352endmenu # "ARM errata workarounds via the alternatives framework"
1353
1354choice
1355 prompt "Page size"
1356 default ARM64_4K_PAGES
1357 help
1358 Page size (translation granule) configuration.
1359
1360config ARM64_4K_PAGES
1361 bool "4KB"
1362 select HAVE_PAGE_SIZE_4KB
1363 help
1364 This feature enables 4KB pages support.
1365
1366config ARM64_16K_PAGES
1367 bool "16KB"
1368 select HAVE_PAGE_SIZE_16KB
1369 help
1370 The system will use 16KB pages support. AArch32 emulation
1371 requires applications compiled with 16K (or a multiple of 16K)
1372 aligned segments.
1373
1374config ARM64_64K_PAGES
1375 bool "64KB"
1376 select HAVE_PAGE_SIZE_64KB
1377 help
1378 This feature enables 64KB pages support (4KB by default)
1379 allowing only two levels of page tables and faster TLB
1380 look-up. AArch32 emulation requires applications compiled
1381 with 64K aligned segments.
1382
1383endchoice
1384
1385choice
1386 prompt "Virtual address space size"
1387 default ARM64_VA_BITS_52
1388 help
1389 Allows choosing one of multiple possible virtual address
1390 space sizes. The level of translation table is determined by
1391 a combination of page size and virtual address space size.
1392
1393config ARM64_VA_BITS_36
1394 bool "36-bit" if EXPERT
1395 depends on PAGE_SIZE_16KB
1396
1397config ARM64_VA_BITS_39
1398 bool "39-bit"
1399 depends on PAGE_SIZE_4KB
1400
1401config ARM64_VA_BITS_42
1402 bool "42-bit"
1403 depends on PAGE_SIZE_64KB
1404
1405config ARM64_VA_BITS_47
1406 bool "47-bit"
1407 depends on PAGE_SIZE_16KB
1408
1409config ARM64_VA_BITS_48
1410 bool "48-bit"
1411
1412config ARM64_VA_BITS_52
1413 bool "52-bit"
1414 help
1415 Enable 52-bit virtual addressing for userspace when explicitly
1416 requested via a hint to mmap(). The kernel will also use 52-bit
1417 virtual addresses for its own mappings (provided HW support for
1418 this feature is available, otherwise it reverts to 48-bit).
1419
1420 NOTE: Enabling 52-bit virtual addressing in conjunction with
1421 ARMv8.3 Pointer Authentication will result in the PAC being
1422 reduced from 7 bits to 3 bits, which may have a significant
1423 impact on its susceptibility to brute-force attacks.
1424
1425 If unsure, select 48-bit virtual addressing instead.
1426
1427endchoice
1428
1429config ARM64_FORCE_52BIT
1430 bool "Force 52-bit virtual addresses for userspace"
1431 depends on ARM64_VA_BITS_52 && EXPERT
1432 help
1433 For systems with 52-bit userspace VAs enabled, the kernel will attempt
1434 to maintain compatibility with older software by providing 48-bit VAs
1435 unless a hint is supplied to mmap.
1436
1437 This configuration option disables the 48-bit compatibility logic, and
1438 forces all userspace addresses to be 52-bit on HW that supports it. One
1439 should only enable this configuration option for stress testing userspace
1440 memory management code. If unsure say N here.
1441
1442config ARM64_VA_BITS
1443 int
1444 default 36 if ARM64_VA_BITS_36
1445 default 39 if ARM64_VA_BITS_39
1446 default 42 if ARM64_VA_BITS_42
1447 default 47 if ARM64_VA_BITS_47
1448 default 48 if ARM64_VA_BITS_48
1449 default 52 if ARM64_VA_BITS_52
1450
1451choice
1452 prompt "Physical address space size"
1453 default ARM64_PA_BITS_48
1454 help
1455 Choose the maximum physical address range that the kernel will
1456 support.
1457
1458config ARM64_PA_BITS_48
1459 bool "48-bit"
1460 depends on ARM64_64K_PAGES || !ARM64_VA_BITS_52
1461
1462config ARM64_PA_BITS_52
1463 bool "52-bit"
1464 depends on ARM64_64K_PAGES || ARM64_VA_BITS_52
1465 help
1466 Enable support for a 52-bit physical address space, introduced as
1467 part of the ARMv8.2-LPA extension.
1468
1469 With this enabled, the kernel will also continue to work on CPUs that
1470 do not support ARMv8.2-LPA, but with some added memory overhead (and
1471 minor performance overhead).
1472
1473endchoice
1474
1475config ARM64_PA_BITS
1476 int
1477 default 48 if ARM64_PA_BITS_48
1478 default 52 if ARM64_PA_BITS_52
1479
1480config ARM64_LPA2
1481 def_bool y
1482 depends on ARM64_PA_BITS_52 && !ARM64_64K_PAGES
1483
1484choice
1485 prompt "Endianness"
1486 default CPU_LITTLE_ENDIAN
1487 help
1488 Select the endianness of data accesses performed by the CPU. Userspace
1489 applications will need to be compiled and linked for the endianness
1490 that is selected here.
1491
1492config CPU_BIG_ENDIAN
1493 bool "Build big-endian kernel"
1494 # https://github.com/llvm/llvm-project/commit/1379b150991f70a5782e9a143c2ba5308da1161c
1495 depends on AS_IS_GNU || AS_VERSION >= 150000
1496 help
1497 Say Y if you plan on running a kernel with a big-endian userspace.
1498
1499config CPU_LITTLE_ENDIAN
1500 bool "Build little-endian kernel"
1501 help
1502 Say Y if you plan on running a kernel with a little-endian userspace.
1503 This is usually the case for distributions targeting arm64.
1504
1505endchoice
1506
1507config SCHED_MC
1508 bool "Multi-core scheduler support"
1509 help
1510 Multi-core scheduler support improves the CPU scheduler's decision
1511 making when dealing with multi-core CPU chips at a cost of slightly
1512 increased overhead in some places. If unsure say N here.
1513
1514config SCHED_CLUSTER
1515 bool "Cluster scheduler support"
1516 help
1517 Cluster scheduler support improves the CPU scheduler's decision
1518 making when dealing with machines that have clusters of CPUs.
1519 Cluster usually means a couple of CPUs which are placed closely
1520 by sharing mid-level caches, last-level cache tags or internal
1521 busses.
1522
1523config SCHED_SMT
1524 bool "SMT scheduler support"
1525 help
1526 Improves the CPU scheduler's decision making when dealing with
1527 MultiThreading at a cost of slightly increased overhead in some
1528 places. If unsure say N here.
1529
1530config NR_CPUS
1531 int "Maximum number of CPUs (2-4096)"
1532 range 2 4096
1533 default "512"
1534
1535config HOTPLUG_CPU
1536 bool "Support for hot-pluggable CPUs"
1537 select GENERIC_IRQ_MIGRATION
1538 help
1539 Say Y here to experiment with turning CPUs off and on. CPUs
1540 can be controlled through /sys/devices/system/cpu.
1541
1542# Common NUMA Features
1543config NUMA
1544 bool "NUMA Memory Allocation and Scheduler Support"
1545 select GENERIC_ARCH_NUMA
1546 select OF_NUMA
1547 select HAVE_SETUP_PER_CPU_AREA
1548 select NEED_PER_CPU_EMBED_FIRST_CHUNK
1549 select NEED_PER_CPU_PAGE_FIRST_CHUNK
1550 select USE_PERCPU_NUMA_NODE_ID
1551 help
1552 Enable NUMA (Non-Uniform Memory Access) support.
1553
1554 The kernel will try to allocate memory used by a CPU on the
1555 local memory of the CPU and add some more
1556 NUMA awareness to the kernel.
1557
1558config NODES_SHIFT
1559 int "Maximum NUMA Nodes (as a power of 2)"
1560 range 1 10
1561 default "4"
1562 depends on NUMA
1563 help
1564 Specify the maximum number of NUMA Nodes available on the target
1565 system. Increases memory reserved to accommodate various tables.
1566
1567source "kernel/Kconfig.hz"
1568
1569config ARCH_SPARSEMEM_ENABLE
1570 def_bool y
1571 select SPARSEMEM_VMEMMAP_ENABLE
1572 select SPARSEMEM_VMEMMAP
1573
1574config HW_PERF_EVENTS
1575 def_bool y
1576 depends on ARM_PMU
1577
1578# Supported by clang >= 7.0 or GCC >= 12.0.0
1579config CC_HAVE_SHADOW_CALL_STACK
1580 def_bool $(cc-option, -fsanitize=shadow-call-stack -ffixed-x18)
1581
1582config PARAVIRT
1583 bool "Enable paravirtualization code"
1584 help
1585 This changes the kernel so it can modify itself when it is run
1586 under a hypervisor, potentially improving performance significantly
1587 over full virtualization.
1588
1589config PARAVIRT_TIME_ACCOUNTING
1590 bool "Paravirtual steal time accounting"
1591 select PARAVIRT
1592 help
1593 Select this option to enable fine granularity task steal time
1594 accounting. Time spent executing other tasks in parallel with
1595 the current vCPU is discounted from the vCPU power. To account for
1596 that, there can be a small performance impact.
1597
1598 If in doubt, say N here.
1599
1600config ARCH_SUPPORTS_KEXEC
1601 def_bool PM_SLEEP_SMP
1602
1603config ARCH_SUPPORTS_KEXEC_FILE
1604 def_bool y
1605
1606config ARCH_SELECTS_KEXEC_FILE
1607 def_bool y
1608 depends on KEXEC_FILE
1609 select HAVE_IMA_KEXEC if IMA
1610
1611config ARCH_SUPPORTS_KEXEC_SIG
1612 def_bool y
1613
1614config ARCH_SUPPORTS_KEXEC_IMAGE_VERIFY_SIG
1615 def_bool y
1616
1617config ARCH_DEFAULT_KEXEC_IMAGE_VERIFY_SIG
1618 def_bool y
1619
1620config ARCH_SUPPORTS_KEXEC_HANDOVER
1621 def_bool y
1622
1623config ARCH_SUPPORTS_CRASH_DUMP
1624 def_bool y
1625
1626config ARCH_DEFAULT_CRASH_DUMP
1627 def_bool y
1628
1629config ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION
1630 def_bool CRASH_RESERVE
1631
1632config TRANS_TABLE
1633 def_bool y
1634 depends on HIBERNATION || KEXEC_CORE
1635
1636config XEN_DOM0
1637 def_bool y
1638 depends on XEN
1639
1640config XEN
1641 bool "Xen guest support on ARM64"
1642 depends on ARM64 && OF
1643 select SWIOTLB_XEN
1644 select PARAVIRT
1645 help
1646 Say Y if you want to run Linux in a Virtual Machine on Xen on ARM64.
1647
1648# include/linux/mmzone.h requires the following to be true:
1649#
1650# MAX_PAGE_ORDER + PAGE_SHIFT <= SECTION_SIZE_BITS
1651#
1652# so the maximum value of MAX_PAGE_ORDER is SECTION_SIZE_BITS - PAGE_SHIFT:
1653#
1654# | SECTION_SIZE_BITS | PAGE_SHIFT | max MAX_PAGE_ORDER | default MAX_PAGE_ORDER |
1655# ----+-------------------+--------------+----------------------+-------------------------+
1656# 4K | 27 | 12 | 15 | 10 |
1657# 16K | 27 | 14 | 13 | 11 |
1658# 64K | 29 | 16 | 13 | 13 |
1659config ARCH_FORCE_MAX_ORDER
1660 int
1661 default "13" if ARM64_64K_PAGES
1662 default "11" if ARM64_16K_PAGES
1663 default "10"
1664 help
1665 The kernel page allocator limits the size of maximal physically
1666 contiguous allocations. The limit is called MAX_PAGE_ORDER and it
1667 defines the maximal power of two of number of pages that can be
1668 allocated as a single contiguous block. This option allows
1669 overriding the default setting when ability to allocate very
1670 large blocks of physically contiguous memory is required.
1671
1672 The maximal size of allocation cannot exceed the size of the
1673 section, so the value of MAX_PAGE_ORDER should satisfy
1674
1675 MAX_PAGE_ORDER + PAGE_SHIFT <= SECTION_SIZE_BITS
1676
1677 Don't change if unsure.
1678
1679config UNMAP_KERNEL_AT_EL0
1680 bool "Unmap kernel when running in userspace (KPTI)" if EXPERT
1681 default y
1682 help
1683 Speculation attacks against some high-performance processors can
1684 be used to bypass MMU permission checks and leak kernel data to
1685 userspace. This can be defended against by unmapping the kernel
1686 when running in userspace, mapping it back in on exception entry
1687 via a trampoline page in the vector table.
1688
1689 If unsure, say Y.
1690
1691config MITIGATE_SPECTRE_BRANCH_HISTORY
1692 bool "Mitigate Spectre style attacks against branch history" if EXPERT
1693 default y
1694 help
1695 Speculation attacks against some high-performance processors can
1696 make use of branch history to influence future speculation.
1697 When taking an exception from user-space, a sequence of branches
1698 or a firmware call overwrites the branch history.
1699
1700config RODATA_FULL_DEFAULT_ENABLED
1701 bool "Apply r/o permissions of VM areas also to their linear aliases"
1702 default y
1703 help
1704 Apply read-only attributes of VM areas to the linear alias of
1705 the backing pages as well. This prevents code or read-only data
1706 from being modified (inadvertently or intentionally) via another
1707 mapping of the same memory page. This additional enhancement can
1708 be turned off at runtime by passing rodata=[off|on] (and turned on
1709 with rodata=full if this option is set to 'n')
1710
1711 This requires the linear region to be mapped down to pages,
1712 which may adversely affect performance in some cases.
1713
1714config ARM64_SW_TTBR0_PAN
1715 bool "Emulate Privileged Access Never using TTBR0_EL1 switching"
1716 depends on !KCSAN
1717 select ARM64_PAN
1718 help
1719 Enabling this option prevents the kernel from accessing
1720 user-space memory directly by pointing TTBR0_EL1 to a reserved
1721 zeroed area and reserved ASID. The user access routines
1722 restore the valid TTBR0_EL1 temporarily.
1723
1724config ARM64_TAGGED_ADDR_ABI
1725 bool "Enable the tagged user addresses syscall ABI"
1726 default y
1727 help
1728 When this option is enabled, user applications can opt in to a
1729 relaxed ABI via prctl() allowing tagged addresses to be passed
1730 to system calls as pointer arguments. For details, see
1731 Documentation/arch/arm64/tagged-address-abi.rst.
1732
1733menuconfig COMPAT
1734 bool "Kernel support for 32-bit EL0"
1735 depends on ARM64_4K_PAGES || EXPERT
1736 select HAVE_UID16
1737 select OLD_SIGSUSPEND3
1738 select COMPAT_OLD_SIGACTION
1739 help
1740 This option enables support for a 32-bit EL0 running under a 64-bit
1741 kernel at EL1. AArch32-specific components such as system calls,
1742 the user helper functions, VFP support and the ptrace interface are
1743 handled appropriately by the kernel.
1744
1745 If you use a page size other than 4KB (i.e, 16KB or 64KB), please be aware
1746 that you will only be able to execute AArch32 binaries that were compiled
1747 with page size aligned segments.
1748
1749 If you want to execute 32-bit userspace applications, say Y.
1750
1751if COMPAT
1752
1753config KUSER_HELPERS
1754 bool "Enable kuser helpers page for 32-bit applications"
1755 default y
1756 help
1757 Warning: disabling this option may break 32-bit user programs.
1758
1759 Provide kuser helpers to compat tasks. The kernel provides
1760 helper code to userspace in read only form at a fixed location
1761 to allow userspace to be independent of the CPU type fitted to
1762 the system. This permits binaries to be run on ARMv4 through
1763 to ARMv8 without modification.
1764
1765 See Documentation/arch/arm/kernel_user_helpers.rst for details.
1766
1767 However, the fixed address nature of these helpers can be used
1768 by ROP (return orientated programming) authors when creating
1769 exploits.
1770
1771 If all of the binaries and libraries which run on your platform
1772 are built specifically for your platform, and make no use of
1773 these helpers, then you can turn this option off to hinder
1774 such exploits. However, in that case, if a binary or library
1775 relying on those helpers is run, it will not function correctly.
1776
1777 Say N here only if you are absolutely certain that you do not
1778 need these helpers; otherwise, the safe option is to say Y.
1779
1780config COMPAT_VDSO
1781 bool "Enable vDSO for 32-bit applications"
1782 depends on !CPU_BIG_ENDIAN
1783 depends on (CC_IS_CLANG && LD_IS_LLD) || "$(CROSS_COMPILE_COMPAT)" != ""
1784 select GENERIC_COMPAT_VDSO
1785 default y
1786 help
1787 Place in the process address space of 32-bit applications an
1788 ELF shared object providing fast implementations of gettimeofday
1789 and clock_gettime.
1790
1791 You must have a 32-bit build of glibc 2.22 or later for programs
1792 to seamlessly take advantage of this.
1793
1794config THUMB2_COMPAT_VDSO
1795 bool "Compile the 32-bit vDSO for Thumb-2 mode" if EXPERT
1796 depends on COMPAT_VDSO
1797 default y
1798 help
1799 Compile the compat vDSO with '-mthumb -fomit-frame-pointer' if y,
1800 otherwise with '-marm'.
1801
1802config COMPAT_ALIGNMENT_FIXUPS
1803 bool "Fix up misaligned multi-word loads and stores in user space"
1804
1805menuconfig ARMV8_DEPRECATED
1806 bool "Emulate deprecated/obsolete ARMv8 instructions"
1807 depends on SYSCTL
1808 help
1809 Legacy software support may require certain instructions
1810 that have been deprecated or obsoleted in the architecture.
1811
1812 Enable this config to enable selective emulation of these
1813 features.
1814
1815 If unsure, say Y
1816
1817if ARMV8_DEPRECATED
1818
1819config SWP_EMULATION
1820 bool "Emulate SWP/SWPB instructions"
1821 help
1822 ARMv8 obsoletes the use of A32 SWP/SWPB instructions such that
1823 they are always undefined. Say Y here to enable software
1824 emulation of these instructions for userspace using LDXR/STXR.
1825 This feature can be controlled at runtime with the abi.swp
1826 sysctl which is disabled by default.
1827
1828 In some older versions of glibc [<=2.8] SWP is used during futex
1829 trylock() operations with the assumption that the code will not
1830 be preempted. This invalid assumption may be more likely to fail
1831 with SWP emulation enabled, leading to deadlock of the user
1832 application.
1833
1834 NOTE: when accessing uncached shared regions, LDXR/STXR rely
1835 on an external transaction monitoring block called a global
1836 monitor to maintain update atomicity. If your system does not
1837 implement a global monitor, this option can cause programs that
1838 perform SWP operations to uncached memory to deadlock.
1839
1840 If unsure, say Y
1841
1842config CP15_BARRIER_EMULATION
1843 bool "Emulate CP15 Barrier instructions"
1844 help
1845 The CP15 barrier instructions - CP15ISB, CP15DSB, and
1846 CP15DMB - are deprecated in ARMv8 (and ARMv7). It is
1847 strongly recommended to use the ISB, DSB, and DMB
1848 instructions instead.
1849
1850 Say Y here to enable software emulation of these
1851 instructions for AArch32 userspace code. When this option is
1852 enabled, CP15 barrier usage is traced which can help
1853 identify software that needs updating. This feature can be
1854 controlled at runtime with the abi.cp15_barrier sysctl.
1855
1856 If unsure, say Y
1857
1858config SETEND_EMULATION
1859 bool "Emulate SETEND instruction"
1860 help
1861 The SETEND instruction alters the data-endianness of the
1862 AArch32 EL0, and is deprecated in ARMv8.
1863
1864 Say Y here to enable software emulation of the instruction
1865 for AArch32 userspace code. This feature can be controlled
1866 at runtime with the abi.setend sysctl.
1867
1868 Note: All the cpus on the system must have mixed endian support at EL0
1869 for this feature to be enabled. If a new CPU - which doesn't support mixed
1870 endian - is hotplugged in after this feature has been enabled, there could
1871 be unexpected results in the applications.
1872
1873 If unsure, say Y
1874endif # ARMV8_DEPRECATED
1875
1876endif # COMPAT
1877
1878menu "ARMv8.1 architectural features"
1879
1880config ARM64_HW_AFDBM
1881 bool "Support for hardware updates of the Access and Dirty page flags"
1882 default y
1883 help
1884 The ARMv8.1 architecture extensions introduce support for
1885 hardware updates of the access and dirty information in page
1886 table entries. When enabled in TCR_EL1 (HA and HD bits) on
1887 capable processors, accesses to pages with PTE_AF cleared will
1888 set this bit instead of raising an access flag fault.
1889 Similarly, writes to read-only pages with the DBM bit set will
1890 clear the read-only bit (AP[2]) instead of raising a
1891 permission fault.
1892
1893 Kernels built with this configuration option enabled continue
1894 to work on pre-ARMv8.1 hardware and the performance impact is
1895 minimal. If unsure, say Y.
1896
1897config ARM64_PAN
1898 bool "Enable support for Privileged Access Never (PAN)"
1899 default y
1900 help
1901 Privileged Access Never (PAN; part of the ARMv8.1 Extensions)
1902 prevents the kernel or hypervisor from accessing user-space (EL0)
1903 memory directly.
1904
1905 Choosing this option will cause any unprotected (not using
1906 copy_to_user et al) memory access to fail with a permission fault.
1907
1908 The feature is detected at runtime, and will remain as a 'nop'
1909 instruction if the cpu does not implement the feature.
1910
1911config ARM64_LSE_ATOMICS
1912 bool
1913 default ARM64_USE_LSE_ATOMICS
1914
1915config ARM64_USE_LSE_ATOMICS
1916 bool "Atomic instructions"
1917 default y
1918 help
1919 As part of the Large System Extensions, ARMv8.1 introduces new
1920 atomic instructions that are designed specifically to scale in
1921 very large systems.
1922
1923 Say Y here to make use of these instructions for the in-kernel
1924 atomic routines. This incurs a small overhead on CPUs that do
1925 not support these instructions.
1926
1927endmenu # "ARMv8.1 architectural features"
1928
1929menu "ARMv8.2 architectural features"
1930
1931config ARM64_PMEM
1932 bool "Enable support for persistent memory"
1933 select ARCH_HAS_PMEM_API
1934 select ARCH_HAS_UACCESS_FLUSHCACHE
1935 help
1936 Say Y to enable support for the persistent memory API based on the
1937 ARMv8.2 DCPoP feature.
1938
1939 The feature is detected at runtime, and the kernel will use DC CVAC
1940 operations if DC CVAP is not supported (following the behaviour of
1941 DC CVAP itself if the system does not define a point of persistence).
1942
1943config ARM64_RAS_EXTN
1944 bool "Enable support for RAS CPU Extensions"
1945 default y
1946 help
1947 CPUs that support the Reliability, Availability and Serviceability
1948 (RAS) Extensions, part of ARMv8.2 are able to track faults and
1949 errors, classify them and report them to software.
1950
1951 On CPUs with these extensions system software can use additional
1952 barriers to determine if faults are pending and read the
1953 classification from a new set of registers.
1954
1955 Selecting this feature will allow the kernel to use these barriers
1956 and access the new registers if the system supports the extension.
1957 Platform RAS features may additionally depend on firmware support.
1958
1959config ARM64_CNP
1960 bool "Enable support for Common Not Private (CNP) translations"
1961 default y
1962 help
1963 Common Not Private (CNP) allows translation table entries to
1964 be shared between different PEs in the same inner shareable
1965 domain, so the hardware can use this fact to optimise the
1966 caching of such entries in the TLB.
1967
1968 Selecting this option allows the CNP feature to be detected
1969 at runtime, and does not affect PEs that do not implement
1970 this feature.
1971
1972endmenu # "ARMv8.2 architectural features"
1973
1974menu "ARMv8.3 architectural features"
1975
1976config ARM64_PTR_AUTH
1977 bool "Enable support for pointer authentication"
1978 default y
1979 help
1980 Pointer authentication (part of the ARMv8.3 Extensions) provides
1981 instructions for signing and authenticating pointers against secret
1982 keys, which can be used to mitigate Return Oriented Programming (ROP)
1983 and other attacks.
1984
1985 This option enables these instructions at EL0 (i.e. for userspace).
1986 Choosing this option will cause the kernel to initialise secret keys
1987 for each process at exec() time, with these keys being
1988 context-switched along with the process.
1989
1990 The feature is detected at runtime. If the feature is not present in
1991 hardware it will not be advertised to userspace/KVM guest nor will it
1992 be enabled.
1993
1994 If the feature is present on the boot CPU but not on a late CPU, then
1995 the late CPU will be parked. Also, if the boot CPU does not have
1996 address auth and the late CPU has then the late CPU will still boot
1997 but with the feature disabled. On such a system, this option should
1998 not be selected.
1999
2000config ARM64_PTR_AUTH_KERNEL
2001 bool "Use pointer authentication for kernel"
2002 default y
2003 depends on ARM64_PTR_AUTH
2004 # Modern compilers insert a .note.gnu.property section note for PAC
2005 # which is only understood by binutils starting with version 2.33.1.
2006 depends on LD_IS_LLD || LD_VERSION >= 23301 || (CC_IS_GCC && GCC_VERSION < 90100)
2007 depends on !CC_IS_CLANG || AS_HAS_CFI_NEGATE_RA_STATE
2008 depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_ARGS)
2009 help
2010 If the compiler supports the -mbranch-protection or
2011 -msign-return-address flag (e.g. GCC 7 or later), then this option
2012 will cause the kernel itself to be compiled with return address
2013 protection. In this case, and if the target hardware is known to
2014 support pointer authentication, then CONFIG_STACKPROTECTOR can be
2015 disabled with minimal loss of protection.
2016
2017 This feature works with FUNCTION_GRAPH_TRACER option only if
2018 DYNAMIC_FTRACE_WITH_ARGS is enabled.
2019
2020config CC_HAS_BRANCH_PROT_PAC_RET
2021 # GCC 9 or later, clang 8 or later
2022 def_bool $(cc-option,-mbranch-protection=pac-ret+leaf)
2023
2024config AS_HAS_CFI_NEGATE_RA_STATE
2025 # binutils 2.34+
2026 def_bool $(as-instr,.cfi_startproc\n.cfi_negate_ra_state\n.cfi_endproc\n)
2027
2028endmenu # "ARMv8.3 architectural features"
2029
2030menu "ARMv8.4 architectural features"
2031
2032config ARM64_AMU_EXTN
2033 bool "Enable support for the Activity Monitors Unit CPU extension"
2034 default y
2035 help
2036 The activity monitors extension is an optional extension introduced
2037 by the ARMv8.4 CPU architecture. This enables support for version 1
2038 of the activity monitors architecture, AMUv1.
2039
2040 To enable the use of this extension on CPUs that implement it, say Y.
2041
2042 Note that for architectural reasons, firmware _must_ implement AMU
2043 support when running on CPUs that present the activity monitors
2044 extension. The required support is present in:
2045 * Version 1.5 and later of the ARM Trusted Firmware
2046
2047 For kernels that have this configuration enabled but boot with broken
2048 firmware, you may need to say N here until the firmware is fixed.
2049 Otherwise you may experience firmware panics or lockups when
2050 accessing the counter registers. Even if you are not observing these
2051 symptoms, the values returned by the register reads might not
2052 correctly reflect reality. Most commonly, the value read will be 0,
2053 indicating that the counter is not enabled.
2054
2055config ARM64_TLB_RANGE
2056 bool "Enable support for tlbi range feature"
2057 default y
2058 help
2059 ARMv8.4-TLBI provides TLBI invalidation instruction that apply to a
2060 range of input addresses.
2061
2062endmenu # "ARMv8.4 architectural features"
2063
2064menu "ARMv8.5 architectural features"
2065
2066config AS_HAS_ARMV8_5
2067 def_bool $(cc-option,-Wa$(comma)-march=armv8.5-a)
2068
2069config ARM64_BTI
2070 bool "Branch Target Identification support"
2071 default y
2072 help
2073 Branch Target Identification (part of the ARMv8.5 Extensions)
2074 provides a mechanism to limit the set of locations to which computed
2075 branch instructions such as BR or BLR can jump.
2076
2077 To make use of BTI on CPUs that support it, say Y.
2078
2079 BTI is intended to provide complementary protection to other control
2080 flow integrity protection mechanisms, such as the Pointer
2081 authentication mechanism provided as part of the ARMv8.3 Extensions.
2082 For this reason, it does not make sense to enable this option without
2083 also enabling support for pointer authentication. Thus, when
2084 enabling this option you should also select ARM64_PTR_AUTH=y.
2085
2086 Userspace binaries must also be specifically compiled to make use of
2087 this mechanism. If you say N here or the hardware does not support
2088 BTI, such binaries can still run, but you get no additional
2089 enforcement of branch destinations.
2090
2091config ARM64_BTI_KERNEL
2092 bool "Use Branch Target Identification for kernel"
2093 default y
2094 depends on ARM64_BTI
2095 depends on ARM64_PTR_AUTH_KERNEL
2096 depends on CC_HAS_BRANCH_PROT_PAC_RET_BTI
2097 # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94697
2098 depends on !CC_IS_GCC || GCC_VERSION >= 100100
2099 # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106671
2100 depends on !CC_IS_GCC
2101 depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_ARGS)
2102 help
2103 Build the kernel with Branch Target Identification annotations
2104 and enable enforcement of this for kernel code. When this option
2105 is enabled and the system supports BTI all kernel code including
2106 modular code must have BTI enabled.
2107
2108config CC_HAS_BRANCH_PROT_PAC_RET_BTI
2109 # GCC 9 or later, clang 8 or later
2110 def_bool $(cc-option,-mbranch-protection=pac-ret+leaf+bti)
2111
2112config ARM64_E0PD
2113 bool "Enable support for E0PD"
2114 default y
2115 help
2116 E0PD (part of the ARMv8.5 extensions) allows us to ensure
2117 that EL0 accesses made via TTBR1 always fault in constant time,
2118 providing similar benefits to KASLR as those provided by KPTI, but
2119 with lower overhead and without disrupting legitimate access to
2120 kernel memory such as SPE.
2121
2122 This option enables E0PD for TTBR1 where available.
2123
2124config ARM64_AS_HAS_MTE
2125 # Initial support for MTE went in binutils 2.32.0, checked with
2126 # ".arch armv8.5-a+memtag" below. However, this was incomplete
2127 # as a late addition to the final architecture spec (LDGM/STGM)
2128 # is only supported in the newer 2.32.x and 2.33 binutils
2129 # versions, hence the extra "stgm" instruction check below.
2130 def_bool $(as-instr,.arch armv8.5-a+memtag\nstgm xzr$(comma)[x0])
2131
2132config ARM64_MTE
2133 bool "Memory Tagging Extension support"
2134 default y
2135 depends on ARM64_AS_HAS_MTE && ARM64_TAGGED_ADDR_ABI
2136 depends on AS_HAS_ARMV8_5
2137 # Required for tag checking in the uaccess routines
2138 select ARM64_PAN
2139 select ARCH_HAS_SUBPAGE_FAULTS
2140 select ARCH_USES_HIGH_VMA_FLAGS
2141 select ARCH_USES_PG_ARCH_2
2142 select ARCH_USES_PG_ARCH_3
2143 help
2144 Memory Tagging (part of the ARMv8.5 Extensions) provides
2145 architectural support for run-time, always-on detection of
2146 various classes of memory error to aid with software debugging
2147 to eliminate vulnerabilities arising from memory-unsafe
2148 languages.
2149
2150 This option enables the support for the Memory Tagging
2151 Extension at EL0 (i.e. for userspace).
2152
2153 Selecting this option allows the feature to be detected at
2154 runtime. Any secondary CPU not implementing this feature will
2155 not be allowed a late bring-up.
2156
2157 Userspace binaries that want to use this feature must
2158 explicitly opt in. The mechanism for the userspace is
2159 described in:
2160
2161 Documentation/arch/arm64/memory-tagging-extension.rst.
2162
2163endmenu # "ARMv8.5 architectural features"
2164
2165menu "ARMv8.7 architectural features"
2166
2167config ARM64_EPAN
2168 bool "Enable support for Enhanced Privileged Access Never (EPAN)"
2169 default y
2170 depends on ARM64_PAN
2171 help
2172 Enhanced Privileged Access Never (EPAN) allows Privileged
2173 Access Never to be used with Execute-only mappings.
2174
2175 The feature is detected at runtime, and will remain disabled
2176 if the cpu does not implement the feature.
2177endmenu # "ARMv8.7 architectural features"
2178
2179config AS_HAS_MOPS
2180 def_bool $(as-instr,.arch_extension mops)
2181
2182menu "ARMv8.9 architectural features"
2183
2184config ARM64_POE
2185 prompt "Permission Overlay Extension"
2186 def_bool y
2187 select ARCH_USES_HIGH_VMA_FLAGS
2188 select ARCH_HAS_PKEYS
2189 help
2190 The Permission Overlay Extension is used to implement Memory
2191 Protection Keys. Memory Protection Keys provides a mechanism for
2192 enforcing page-based protections, but without requiring modification
2193 of the page tables when an application changes protection domains.
2194
2195 For details, see Documentation/core-api/protection-keys.rst
2196
2197 If unsure, say y.
2198
2199config ARCH_PKEY_BITS
2200 int
2201 default 3
2202
2203config ARM64_HAFT
2204 bool "Support for Hardware managed Access Flag for Table Descriptors"
2205 depends on ARM64_HW_AFDBM
2206 default y
2207 help
2208 The ARMv8.9/ARMv9.5 introduces the feature Hardware managed Access
2209 Flag for Table descriptors. When enabled an architectural executed
2210 memory access will update the Access Flag in each Table descriptor
2211 which is accessed during the translation table walk and for which
2212 the Access Flag is 0. The Access Flag of the Table descriptor use
2213 the same bit of PTE_AF.
2214
2215 The feature will only be enabled if all the CPUs in the system
2216 support this feature. If unsure, say Y.
2217
2218endmenu # "ARMv8.9 architectural features"
2219
2220menu "v9.4 architectural features"
2221
2222config ARM64_GCS
2223 bool "Enable support for Guarded Control Stack (GCS)"
2224 default y
2225 select ARCH_HAS_USER_SHADOW_STACK
2226 select ARCH_USES_HIGH_VMA_FLAGS
2227 depends on !UPROBES
2228 help
2229 Guarded Control Stack (GCS) provides support for a separate
2230 stack with restricted access which contains only return
2231 addresses. This can be used to harden against some attacks
2232 by comparing return address used by the program with what is
2233 stored in the GCS, and may also be used to efficiently obtain
2234 the call stack for applications such as profiling.
2235
2236 The feature is detected at runtime, and will remain disabled
2237 if the system does not implement the feature.
2238
2239endmenu # "v9.4 architectural features"
2240
2241config ARM64_SVE
2242 bool "ARM Scalable Vector Extension support"
2243 default y
2244 help
2245 The Scalable Vector Extension (SVE) is an extension to the AArch64
2246 execution state which complements and extends the SIMD functionality
2247 of the base architecture to support much larger vectors and to enable
2248 additional vectorisation opportunities.
2249
2250 To enable use of this extension on CPUs that implement it, say Y.
2251
2252 On CPUs that support the SVE2 extensions, this option will enable
2253 those too.
2254
2255 Note that for architectural reasons, firmware _must_ implement SVE
2256 support when running on SVE capable hardware. The required support
2257 is present in:
2258
2259 * version 1.5 and later of the ARM Trusted Firmware
2260 * the AArch64 boot wrapper since commit 5e1261e08abf
2261 ("bootwrapper: SVE: Enable SVE for EL2 and below").
2262
2263 For other firmware implementations, consult the firmware documentation
2264 or vendor.
2265
2266 If you need the kernel to boot on SVE-capable hardware with broken
2267 firmware, you may need to say N here until you get your firmware
2268 fixed. Otherwise, you may experience firmware panics or lockups when
2269 booting the kernel. If unsure and you are not observing these
2270 symptoms, you should assume that it is safe to say Y.
2271
2272config ARM64_SME
2273 bool "ARM Scalable Matrix Extension support"
2274 default y
2275 depends on ARM64_SVE
2276 help
2277 The Scalable Matrix Extension (SME) is an extension to the AArch64
2278 execution state which utilises a substantial subset of the SVE
2279 instruction set, together with the addition of new architectural
2280 register state capable of holding two dimensional matrix tiles to
2281 enable various matrix operations.
2282
2283config ARM64_PSEUDO_NMI
2284 bool "Support for NMI-like interrupts"
2285 select ARM_GIC_V3
2286 help
2287 Adds support for mimicking Non-Maskable Interrupts through the use of
2288 GIC interrupt priority. This support requires version 3 or later of
2289 ARM GIC.
2290
2291 This high priority configuration for interrupts needs to be
2292 explicitly enabled by setting the kernel parameter
2293 "irqchip.gicv3_pseudo_nmi" to 1.
2294
2295 If unsure, say N
2296
2297if ARM64_PSEUDO_NMI
2298config ARM64_DEBUG_PRIORITY_MASKING
2299 bool "Debug interrupt priority masking"
2300 help
2301 This adds runtime checks to functions enabling/disabling
2302 interrupts when using priority masking. The additional checks verify
2303 the validity of ICC_PMR_EL1 when calling concerned functions.
2304
2305 If unsure, say N
2306endif # ARM64_PSEUDO_NMI
2307
2308config RELOCATABLE
2309 bool "Build a relocatable kernel image" if EXPERT
2310 select ARCH_HAS_RELR
2311 default y
2312 help
2313 This builds the kernel as a Position Independent Executable (PIE),
2314 which retains all relocation metadata required to relocate the
2315 kernel binary at runtime to a different virtual address than the
2316 address it was linked at.
2317 Since AArch64 uses the RELA relocation format, this requires a
2318 relocation pass at runtime even if the kernel is loaded at the
2319 same address it was linked at.
2320
2321config RANDOMIZE_BASE
2322 bool "Randomize the address of the kernel image"
2323 select RELOCATABLE
2324 help
2325 Randomizes the virtual address at which the kernel image is
2326 loaded, as a security feature that deters exploit attempts
2327 relying on knowledge of the location of kernel internals.
2328
2329 It is the bootloader's job to provide entropy, by passing a
2330 random u64 value in /chosen/kaslr-seed at kernel entry.
2331
2332 When booting via the UEFI stub, it will invoke the firmware's
2333 EFI_RNG_PROTOCOL implementation (if available) to supply entropy
2334 to the kernel proper. In addition, it will randomise the physical
2335 location of the kernel Image as well.
2336
2337 If unsure, say N.
2338
2339config RANDOMIZE_MODULE_REGION_FULL
2340 bool "Randomize the module region over a 2 GB range"
2341 depends on RANDOMIZE_BASE
2342 default y
2343 help
2344 Randomizes the location of the module region inside a 2 GB window
2345 covering the core kernel. This way, it is less likely for modules
2346 to leak information about the location of core kernel data structures
2347 but it does imply that function calls between modules and the core
2348 kernel will need to be resolved via veneers in the module PLT.
2349
2350 When this option is not set, the module region will be randomized over
2351 a limited range that contains the [_stext, _etext] interval of the
2352 core kernel, so branch relocations are almost always in range unless
2353 the region is exhausted. In this particular case of region
2354 exhaustion, modules might be able to fall back to a larger 2GB area.
2355
2356config CC_HAVE_STACKPROTECTOR_SYSREG
2357 def_bool $(cc-option,-mstack-protector-guard=sysreg -mstack-protector-guard-reg=sp_el0 -mstack-protector-guard-offset=0)
2358
2359config STACKPROTECTOR_PER_TASK
2360 def_bool y
2361 depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_SYSREG
2362
2363config UNWIND_PATCH_PAC_INTO_SCS
2364 bool "Enable shadow call stack dynamically using code patching"
2365 # needs Clang with https://github.com/llvm/llvm-project/commit/de07cde67b5d205d58690be012106022aea6d2b3 incorporated
2366 depends on CC_IS_CLANG && CLANG_VERSION >= 150000
2367 depends on ARM64_PTR_AUTH_KERNEL && CC_HAS_BRANCH_PROT_PAC_RET
2368 depends on SHADOW_CALL_STACK
2369 select UNWIND_TABLES
2370 select DYNAMIC_SCS
2371
2372config ARM64_CONTPTE
2373 bool "Contiguous PTE mappings for user memory" if EXPERT
2374 depends on TRANSPARENT_HUGEPAGE
2375 default y
2376 help
2377 When enabled, user mappings are configured using the PTE contiguous
2378 bit, for any mappings that meet the size and alignment requirements.
2379 This reduces TLB pressure and improves performance.
2380
2381endmenu # "Kernel Features"
2382
2383menu "Boot options"
2384
2385config ARM64_ACPI_PARKING_PROTOCOL
2386 bool "Enable support for the ARM64 ACPI parking protocol"
2387 depends on ACPI
2388 help
2389 Enable support for the ARM64 ACPI parking protocol. If disabled
2390 the kernel will not allow booting through the ARM64 ACPI parking
2391 protocol even if the corresponding data is present in the ACPI
2392 MADT table.
2393
2394config CMDLINE
2395 string "Default kernel command string"
2396 default ""
2397 help
2398 Provide a set of default command-line options at build time by
2399 entering them here. As a minimum, you should specify the the
2400 root device (e.g. root=/dev/nfs).
2401
2402choice
2403 prompt "Kernel command line type"
2404 depends on CMDLINE != ""
2405 default CMDLINE_FROM_BOOTLOADER
2406 help
2407 Choose how the kernel will handle the provided default kernel
2408 command line string.
2409
2410config CMDLINE_FROM_BOOTLOADER
2411 bool "Use bootloader kernel arguments if available"
2412 help
2413 Uses the command-line options passed by the boot loader. If
2414 the boot loader doesn't provide any, the default kernel command
2415 string provided in CMDLINE will be used.
2416
2417config CMDLINE_FORCE
2418 bool "Always use the default kernel command string"
2419 help
2420 Always use the default kernel command string, even if the boot
2421 loader passes other arguments to the kernel.
2422 This is useful if you cannot or don't want to change the
2423 command-line options your boot loader passes to the kernel.
2424
2425endchoice
2426
2427config EFI_STUB
2428 bool
2429
2430config EFI
2431 bool "UEFI runtime support"
2432 depends on OF && !CPU_BIG_ENDIAN
2433 depends on KERNEL_MODE_NEON
2434 select ARCH_SUPPORTS_ACPI
2435 select LIBFDT
2436 select UCS2_STRING
2437 select EFI_PARAMS_FROM_FDT
2438 select EFI_RUNTIME_WRAPPERS
2439 select EFI_STUB
2440 select EFI_GENERIC_STUB
2441 imply IMA_SECURE_AND_OR_TRUSTED_BOOT
2442 default y
2443 help
2444 This option provides support for runtime services provided
2445 by UEFI firmware (such as non-volatile variables, realtime
2446 clock, and platform reset). A UEFI stub is also provided to
2447 allow the kernel to be booted as an EFI application. This
2448 is only useful on systems that have UEFI firmware.
2449
2450config COMPRESSED_INSTALL
2451 bool "Install compressed image by default"
2452 help
2453 This makes the regular "make install" install the compressed
2454 image we built, not the legacy uncompressed one.
2455
2456 You can check that a compressed image works for you by doing
2457 "make zinstall" first, and verifying that everything is fine
2458 in your environment before making "make install" do this for
2459 you.
2460
2461config DMI
2462 bool "Enable support for SMBIOS (DMI) tables"
2463 depends on EFI
2464 default y
2465 help
2466 This enables SMBIOS/DMI feature for systems.
2467
2468 This option is only useful on systems that have UEFI firmware.
2469 However, even with this option, the resultant kernel should
2470 continue to boot on existing non-UEFI platforms.
2471
2472endmenu # "Boot options"
2473
2474menu "Power management options"
2475
2476source "kernel/power/Kconfig"
2477
2478config ARCH_HIBERNATION_POSSIBLE
2479 def_bool y
2480 depends on CPU_PM
2481
2482config ARCH_HIBERNATION_HEADER
2483 def_bool y
2484 depends on HIBERNATION
2485
2486config ARCH_SUSPEND_POSSIBLE
2487 def_bool y
2488
2489endmenu # "Power management options"
2490
2491menu "CPU Power Management"
2492
2493source "drivers/cpuidle/Kconfig"
2494
2495source "drivers/cpufreq/Kconfig"
2496
2497endmenu # "CPU Power Management"
2498
2499source "drivers/acpi/Kconfig"
2500
2501source "arch/arm64/kvm/Kconfig"
2502