xref: /linux/arch/arm64/Kconfig (revision 2f8aed5e97fdde7e295a8f0ff0d22a5f1d41b188)
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_CPU_CACHE_INVALIDATE_MEMREGION
25	select ARCH_HAS_CURRENT_STACK_POINTER
26	select ARCH_HAS_DEBUG_VIRTUAL
27	select ARCH_HAS_DEBUG_VM_PGTABLE
28	select ARCH_HAS_DMA_OPS if XEN
29	select ARCH_HAS_DMA_PREP_COHERENT
30	select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI
31	select ARCH_HAS_FAST_MULTIPLIER
32	select ARCH_HAS_FORTIFY_SOURCE
33	select ARCH_HAS_GCOV_PROFILE_ALL
34	select ARCH_HAS_GIGANTIC_PAGE
35	select ARCH_HAS_KCOV
36	select ARCH_HAS_KERNEL_FPU_SUPPORT if KERNEL_MODE_NEON
37	select ARCH_HAS_KEEPINITRD
38	select ARCH_HAS_MEMBARRIER_SYNC_CORE
39	select ARCH_HAS_MEM_ENCRYPT
40	select ARCH_SUPPORTS_MSEAL_SYSTEM_MAPPINGS
41	select ARCH_HAS_NMI_SAFE_THIS_CPU_OPS
42	select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
43	select ARCH_HAS_NONLEAF_PMD_YOUNG if ARM64_HAFT
44	select ARCH_HAS_PREEMPT_LAZY
45	select ARCH_HAS_PTDUMP
46	select ARCH_HAS_PTE_SPECIAL
47	select ARCH_HAS_HW_PTE_YOUNG
48	select ARCH_HAS_SETUP_DMA_OPS
49	select ARCH_HAS_SET_DIRECT_MAP
50	select ARCH_HAS_SET_MEMORY
51	select ARCH_HAS_FORCE_DMA_UNENCRYPTED
52	select ARCH_STACKWALK
53	select ARCH_HAS_STRICT_KERNEL_RWX
54	select ARCH_HAS_STRICT_MODULE_RWX
55	select ARCH_HAS_SYNC_DMA_FOR_DEVICE
56	select ARCH_HAS_SYNC_DMA_FOR_CPU
57	select ARCH_HAS_SYSCALL_WRAPPER
58	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
59	select ARCH_HAS_ZONE_DMA_SET if EXPERT
60	select ARCH_HAVE_ELF_PROT
61	select ARCH_HAVE_NMI_SAFE_CMPXCHG
62	select ARCH_HAVE_TRACE_MMIO_ACCESS
63	select ARCH_INLINE_READ_LOCK if !PREEMPTION
64	select ARCH_INLINE_READ_LOCK_BH if !PREEMPTION
65	select ARCH_INLINE_READ_LOCK_IRQ if !PREEMPTION
66	select ARCH_INLINE_READ_LOCK_IRQSAVE if !PREEMPTION
67	select ARCH_INLINE_READ_UNLOCK if !PREEMPTION
68	select ARCH_INLINE_READ_UNLOCK_BH if !PREEMPTION
69	select ARCH_INLINE_READ_UNLOCK_IRQ if !PREEMPTION
70	select ARCH_INLINE_READ_UNLOCK_IRQRESTORE if !PREEMPTION
71	select ARCH_INLINE_WRITE_LOCK if !PREEMPTION
72	select ARCH_INLINE_WRITE_LOCK_BH if !PREEMPTION
73	select ARCH_INLINE_WRITE_LOCK_IRQ if !PREEMPTION
74	select ARCH_INLINE_WRITE_LOCK_IRQSAVE if !PREEMPTION
75	select ARCH_INLINE_WRITE_UNLOCK if !PREEMPTION
76	select ARCH_INLINE_WRITE_UNLOCK_BH if !PREEMPTION
77	select ARCH_INLINE_WRITE_UNLOCK_IRQ if !PREEMPTION
78	select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE if !PREEMPTION
79	select ARCH_INLINE_SPIN_TRYLOCK if !PREEMPTION
80	select ARCH_INLINE_SPIN_TRYLOCK_BH if !PREEMPTION
81	select ARCH_INLINE_SPIN_LOCK if !PREEMPTION
82	select ARCH_INLINE_SPIN_LOCK_BH if !PREEMPTION
83	select ARCH_INLINE_SPIN_LOCK_IRQ if !PREEMPTION
84	select ARCH_INLINE_SPIN_LOCK_IRQSAVE if !PREEMPTION
85	select ARCH_INLINE_SPIN_UNLOCK if !PREEMPTION
86	select ARCH_INLINE_SPIN_UNLOCK_BH if !PREEMPTION
87	select ARCH_INLINE_SPIN_UNLOCK_IRQ if !PREEMPTION
88	select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE if !PREEMPTION
89	select ARCH_KEEP_MEMBLOCK
90	select ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE
91	select ARCH_USE_CMPXCHG_LOCKREF
92	select ARCH_USE_GNU_PROPERTY
93	select ARCH_USE_MEMTEST
94	select ARCH_USE_QUEUED_RWLOCKS
95	select ARCH_USE_QUEUED_SPINLOCKS
96	select ARCH_USE_SYM_ANNOTATIONS
97	select ARCH_SUPPORTS_DEBUG_PAGEALLOC
98	select ARCH_SUPPORTS_HUGETLBFS
99	select ARCH_SUPPORTS_MEMORY_FAILURE
100	select ARCH_SUPPORTS_SHADOW_CALL_STACK if CC_HAVE_SHADOW_CALL_STACK
101	select ARCH_SUPPORTS_LTO_CLANG if CPU_LITTLE_ENDIAN
102	select ARCH_SUPPORTS_LTO_CLANG_THIN
103	select ARCH_SUPPORTS_CFI
104	select ARCH_SUPPORTS_ATOMIC_RMW
105	select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
106	select ARCH_SUPPORTS_NUMA_BALANCING
107	select ARCH_SUPPORTS_PAGE_TABLE_CHECK
108	select ARCH_SUPPORTS_PER_VMA_LOCK
109	select ARCH_SUPPORTS_HUGE_PFNMAP if TRANSPARENT_HUGEPAGE
110	select ARCH_SUPPORTS_RT
111	select ARCH_SUPPORTS_SCHED_SMT
112	select ARCH_SUPPORTS_SCHED_CLUSTER
113	select ARCH_SUPPORTS_SCHED_MC
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_GIC_V5
133	select ARM_PSCI_FW
134	select BUILDTIME_TABLE_SORT
135	select CLONE_BACKWARDS
136	select COMMON_CLK
137	select CPU_PM if (SUSPEND || CPU_IDLE)
138	select CPUMASK_OFFSTACK if NR_CPUS > 256
139	select DCACHE_WORD_ACCESS
140	select HAVE_EXTRA_IPI_TRACEPOINTS
141	select DYNAMIC_FTRACE if FUNCTION_TRACER
142	select DMA_BOUNCE_UNALIGNED_KMALLOC
143	select DMA_DIRECT_REMAP
144	select EDAC_SUPPORT
145	select FRAME_POINTER
146	select FUNCTION_ALIGNMENT_4B
147	select FUNCTION_ALIGNMENT_8B if DYNAMIC_FTRACE_WITH_CALL_OPS
148	select GENERIC_ALLOCATOR
149	select GENERIC_ARCH_TOPOLOGY
150	select GENERIC_CLOCKEVENTS_BROADCAST
151	select GENERIC_CPU_AUTOPROBE
152	select GENERIC_CPU_CACHE_MAINTENANCE
153	select GENERIC_CPU_DEVICES
154	select GENERIC_CPU_VULNERABILITIES
155	select GENERIC_EARLY_IOREMAP
156	select GENERIC_IDLE_POLL_SETUP
157	select GENERIC_IOREMAP
158	select GENERIC_IRQ_ENTRY
159	select GENERIC_IRQ_IPI
160	select GENERIC_IRQ_KEXEC_CLEAR_VM_FORWARD
161	select GENERIC_IRQ_PROBE
162	select GENERIC_IRQ_SHOW
163	select GENERIC_IRQ_SHOW_LEVEL
164	select GENERIC_LIB_DEVMEM_IS_ALLOWED
165	select GENERIC_PCI_IOMAP
166	select GENERIC_SCHED_CLOCK
167	select GENERIC_SMP_IDLE_THREAD
168	select GENERIC_TIME_VSYSCALL
169	select GENERIC_GETTIMEOFDAY
170	select HARDIRQS_SW_RESEND
171	select HAS_IOPORT
172	select HAVE_MOVE_PMD
173	select HAVE_MOVE_PUD
174	select HAVE_PCI
175	select HAVE_ACPI_APEI if (ACPI && EFI)
176	select HAVE_ALIGNED_STRUCT_PAGE
177	select HAVE_ARCH_AUDITSYSCALL
178	select HAVE_ARCH_BITREVERSE
179	select HAVE_ARCH_COMPILER_H
180	select HAVE_ARCH_HUGE_VMALLOC
181	select HAVE_ARCH_HUGE_VMAP
182	select HAVE_ARCH_JUMP_LABEL
183	select HAVE_ARCH_JUMP_LABEL_RELATIVE
184	select HAVE_ARCH_KASAN
185	select HAVE_ARCH_KASAN_VMALLOC
186	select HAVE_ARCH_KASAN_SW_TAGS
187	select HAVE_ARCH_KASAN_HW_TAGS if ARM64_MTE
188	# Some instrumentation may be unsound, hence EXPERT
189	select HAVE_ARCH_KCSAN if EXPERT
190	select HAVE_ARCH_KFENCE
191	select HAVE_ARCH_KGDB
192	select HAVE_ARCH_KSTACK_ERASE
193	select HAVE_ARCH_MMAP_RND_BITS
194	select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT
195	select HAVE_ARCH_PREL32_RELOCATIONS
196	select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET
197	select HAVE_ARCH_SECCOMP_FILTER
198	select HAVE_ARCH_THREAD_STRUCT_WHITELIST
199	select HAVE_ARCH_TRACEHOOK
200	select HAVE_ARCH_TRANSPARENT_HUGEPAGE
201	select HAVE_ARCH_VMAP_STACK
202	select HAVE_ARM_SMCCC
203	select HAVE_ASM_MODVERSIONS
204	select HAVE_EBPF_JIT
205	select HAVE_C_RECORDMCOUNT
206	select HAVE_CMPXCHG_DOUBLE
207	select HAVE_CMPXCHG_LOCAL
208	select HAVE_CONTEXT_TRACKING_USER
209	select HAVE_DEBUG_KMEMLEAK
210	select HAVE_DMA_CONTIGUOUS
211	select HAVE_DYNAMIC_FTRACE
212	select HAVE_DYNAMIC_FTRACE_WITH_ARGS \
213		if (GCC_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS || \
214		    CLANG_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS)
215	select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS \
216		if DYNAMIC_FTRACE_WITH_ARGS && DYNAMIC_FTRACE_WITH_CALL_OPS
217	select HAVE_DYNAMIC_FTRACE_WITH_CALL_OPS \
218		if (DYNAMIC_FTRACE_WITH_ARGS && !CFI && \
219		    (CC_IS_CLANG || !CC_OPTIMIZE_FOR_SIZE))
220	select FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY \
221		if DYNAMIC_FTRACE_WITH_ARGS
222	select HAVE_SAMPLE_FTRACE_DIRECT
223	select HAVE_SAMPLE_FTRACE_DIRECT_MULTI
224	select HAVE_BUILDTIME_MCOUNT_SORT
225	select HAVE_EFFICIENT_UNALIGNED_ACCESS
226	select HAVE_GUP_FAST
227	select HAVE_FTRACE_GRAPH_FUNC
228	select HAVE_FUNCTION_TRACER
229	select HAVE_FUNCTION_ERROR_INJECTION
230	select HAVE_FUNCTION_GRAPH_FREGS
231	select HAVE_FUNCTION_GRAPH_TRACER
232	select HAVE_GCC_PLUGINS
233	select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && \
234		HW_PERF_EVENTS && HAVE_PERF_EVENTS_NMI
235	select HAVE_HW_BREAKPOINT if PERF_EVENTS
236	select HAVE_IOREMAP_PROT
237	select HAVE_IRQ_TIME_ACCOUNTING
238	select HAVE_LIVEPATCH
239	select HAVE_MOD_ARCH_SPECIFIC
240	select HAVE_NMI
241	select HAVE_PERF_EVENTS
242	select HAVE_PERF_EVENTS_NMI if ARM64_PSEUDO_NMI
243	select HAVE_PERF_REGS
244	select HAVE_PERF_USER_STACK_DUMP
245	select HAVE_PREEMPT_DYNAMIC_KEY
246	select HAVE_REGS_AND_STACK_ACCESS_API
247	select HAVE_RELIABLE_STACKTRACE
248	select HAVE_POSIX_CPU_TIMERS_TASK_WORK
249	select HAVE_FUNCTION_ARG_ACCESS_API
250	select MMU_GATHER_RCU_TABLE_FREE
251	select HAVE_RSEQ
252	select HAVE_RUST if RUSTC_SUPPORTS_ARM64
253	select HAVE_STACKPROTECTOR
254	select HAVE_SYSCALL_TRACEPOINTS
255	select HAVE_KPROBES
256	select HAVE_KRETPROBES
257	select HAVE_GENERIC_VDSO
258	select HOTPLUG_CORE_SYNC_DEAD if HOTPLUG_CPU
259	select HOTPLUG_SMT if HOTPLUG_CPU
260	select IRQ_DOMAIN
261	select IRQ_FORCED_THREADING
262	select JUMP_LABEL
263	select KASAN_VMALLOC if KASAN
264	select LOCK_MM_AND_FIND_VMA
265	select MODULES_USE_ELF_RELA
266	select NEED_DMA_MAP_STATE
267	select NEED_SG_DMA_LENGTH
268	select OF
269	select OF_EARLY_FLATTREE
270	select PCI_DOMAINS_GENERIC if PCI
271	select PCI_ECAM if (ACPI && PCI)
272	select PCI_SYSCALL if PCI
273	select POWER_RESET
274	select POWER_SUPPLY
275	select SPARSE_IRQ
276	select SWIOTLB
277	select SYSCTL_EXCEPTION_TRACE
278	select THREAD_INFO_IN_TASK
279	select HAVE_ARCH_USERFAULTFD_MINOR if USERFAULTFD
280	select HAVE_ARCH_USERFAULTFD_WP if USERFAULTFD
281	select TRACE_IRQFLAGS_SUPPORT
282	select TRACE_IRQFLAGS_NMI_SUPPORT
283	select HAVE_SOFTIRQ_ON_OWN_STACK
284	select USER_STACKTRACE_SUPPORT
285	select VDSO_GETRANDOM
286	select VMAP_STACK
287	help
288	  ARM 64-bit (AArch64) Linux support.
289
290config RUSTC_SUPPORTS_ARM64
291	def_bool y
292	depends on CPU_LITTLE_ENDIAN
293	# Shadow call stack is only supported on certain rustc versions.
294	#
295	# When using the UNWIND_PATCH_PAC_INTO_SCS option, rustc version 1.80+ is
296	# required due to use of the -Zfixed-x18 flag.
297	#
298	# Otherwise, rustc version 1.82+ is required due to use of the
299	# -Zsanitizer=shadow-call-stack flag.
300	depends on !SHADOW_CALL_STACK || RUSTC_VERSION >= 108200 || RUSTC_VERSION >= 108000 && UNWIND_PATCH_PAC_INTO_SCS
301
302config CLANG_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS
303	def_bool CC_IS_CLANG
304	# https://github.com/ClangBuiltLinux/linux/issues/1507
305	depends on AS_IS_GNU || (AS_IS_LLVM && (LD_IS_LLD || LD_VERSION >= 23600))
306
307config GCC_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS
308	def_bool CC_IS_GCC
309	depends on $(cc-option,-fpatchable-function-entry=2)
310
311config 64BIT
312	def_bool y
313
314config MMU
315	def_bool y
316
317config ARM64_CONT_PTE_SHIFT
318	int
319	default 5 if PAGE_SIZE_64KB
320	default 7 if PAGE_SIZE_16KB
321	default 4
322
323config ARM64_CONT_PMD_SHIFT
324	int
325	default 5 if PAGE_SIZE_64KB
326	default 5 if PAGE_SIZE_16KB
327	default 4
328
329config ARCH_MMAP_RND_BITS_MIN
330	default 14 if PAGE_SIZE_64KB
331	default 16 if PAGE_SIZE_16KB
332	default 18
333
334# max bits determined by the following formula:
335#  VA_BITS - PTDESC_TABLE_SHIFT
336config ARCH_MMAP_RND_BITS_MAX
337	default 19 if ARM64_VA_BITS=36
338	default 24 if ARM64_VA_BITS=39
339	default 27 if ARM64_VA_BITS=42
340	default 30 if ARM64_VA_BITS=47
341	default 29 if (ARM64_VA_BITS=48 || ARM64_VA_BITS=52) && ARM64_64K_PAGES
342	default 31 if (ARM64_VA_BITS=48 || ARM64_VA_BITS=52) && ARM64_16K_PAGES
343	default 33 if (ARM64_VA_BITS=48 || ARM64_VA_BITS=52)
344	default 14 if ARM64_64K_PAGES
345	default 16 if ARM64_16K_PAGES
346	default 18
347
348config ARCH_MMAP_RND_COMPAT_BITS_MIN
349	default 7 if ARM64_64K_PAGES
350	default 9 if ARM64_16K_PAGES
351	default 11
352
353config ARCH_MMAP_RND_COMPAT_BITS_MAX
354	default 16
355
356config NO_IOPORT_MAP
357	def_bool y if !PCI
358
359config STACKTRACE_SUPPORT
360	def_bool y
361
362config ILLEGAL_POINTER_VALUE
363	hex
364	default 0xdead000000000000
365
366config LOCKDEP_SUPPORT
367	def_bool y
368
369config GENERIC_BUG
370	def_bool y
371	depends on BUG
372
373config GENERIC_BUG_RELATIVE_POINTERS
374	def_bool y
375	depends on GENERIC_BUG
376
377config GENERIC_HWEIGHT
378	def_bool y
379
380config GENERIC_CSUM
381	def_bool y
382
383config GENERIC_CALIBRATE_DELAY
384	def_bool y
385
386config SMP
387	def_bool y
388
389config KERNEL_MODE_NEON
390	def_bool y
391
392config FIX_EARLYCON_MEM
393	def_bool y
394
395config PGTABLE_LEVELS
396	int
397	default 2 if ARM64_16K_PAGES && ARM64_VA_BITS_36
398	default 2 if ARM64_64K_PAGES && ARM64_VA_BITS_42
399	default 3 if ARM64_64K_PAGES && (ARM64_VA_BITS_48 || ARM64_VA_BITS_52)
400	default 3 if ARM64_4K_PAGES && ARM64_VA_BITS_39
401	default 3 if ARM64_16K_PAGES && ARM64_VA_BITS_47
402	default 4 if ARM64_16K_PAGES && (ARM64_VA_BITS_48 || ARM64_VA_BITS_52)
403	default 4 if !ARM64_64K_PAGES && ARM64_VA_BITS_48
404	default 5 if ARM64_4K_PAGES && ARM64_VA_BITS_52
405
406config ARCH_SUPPORTS_UPROBES
407	def_bool y
408
409config ARCH_PROC_KCORE_TEXT
410	def_bool y
411
412config BROKEN_GAS_INST
413	def_bool !$(as-instr,1:\n.inst 0\n.rept . - 1b\n\nnop\n.endr\n)
414
415config BUILTIN_RETURN_ADDRESS_STRIPS_PAC
416	bool
417	# Clang's __builtin_return_address() strips the PAC since 12.0.0
418	# https://github.com/llvm/llvm-project/commit/2a96f47c5ffca84cd774ad402cacd137f4bf45e2
419	default y if CC_IS_CLANG
420	# GCC's __builtin_return_address() strips the PAC since 11.1.0,
421	# and this was backported to 10.2.0, 9.4.0, 8.5.0, but not earlier
422	# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94891
423	default y if CC_IS_GCC && (GCC_VERSION >= 110100)
424	default y if CC_IS_GCC && (GCC_VERSION >= 100200) && (GCC_VERSION < 110000)
425	default y if CC_IS_GCC && (GCC_VERSION >=  90400) && (GCC_VERSION < 100000)
426	default y if CC_IS_GCC && (GCC_VERSION >=  80500) && (GCC_VERSION <  90000)
427	default n
428
429config KASAN_SHADOW_OFFSET
430	hex
431	depends on KASAN_GENERIC || KASAN_SW_TAGS
432	default 0xdfff800000000000 if (ARM64_VA_BITS_48 || (ARM64_VA_BITS_52 && !ARM64_16K_PAGES)) && !KASAN_SW_TAGS
433	default 0xdfffc00000000000 if (ARM64_VA_BITS_47 || ARM64_VA_BITS_52) && ARM64_16K_PAGES && !KASAN_SW_TAGS
434	default 0xdffffe0000000000 if ARM64_VA_BITS_42 && !KASAN_SW_TAGS
435	default 0xdfffffc000000000 if ARM64_VA_BITS_39 && !KASAN_SW_TAGS
436	default 0xdffffff800000000 if ARM64_VA_BITS_36 && !KASAN_SW_TAGS
437	default 0xefff800000000000 if (ARM64_VA_BITS_48 || (ARM64_VA_BITS_52 && !ARM64_16K_PAGES)) && KASAN_SW_TAGS
438	default 0xefffc00000000000 if (ARM64_VA_BITS_47 || ARM64_VA_BITS_52) && ARM64_16K_PAGES && KASAN_SW_TAGS
439	default 0xeffffe0000000000 if ARM64_VA_BITS_42 && KASAN_SW_TAGS
440	default 0xefffffc000000000 if ARM64_VA_BITS_39 && KASAN_SW_TAGS
441	default 0xeffffff800000000 if ARM64_VA_BITS_36 && KASAN_SW_TAGS
442	default 0xffffffffffffffff
443
444config UNWIND_TABLES
445	bool
446
447source "arch/arm64/Kconfig.platforms"
448
449menu "Kernel Features"
450
451menu "ARM errata workarounds via the alternatives framework"
452
453config AMPERE_ERRATUM_AC03_CPU_38
454        bool "AmpereOne: AC03_CPU_38: Certain bits in the Virtualization Translation Control Register and Translation Control Registers do not follow RES0 semantics"
455	default y
456	help
457	  This option adds an alternative code sequence to work around Ampere
458	  errata AC03_CPU_38 and AC04_CPU_10 on AmpereOne.
459
460	  The affected design reports FEAT_HAFDBS as not implemented in
461	  ID_AA64MMFR1_EL1.HAFDBS, but (V)TCR_ELx.{HA,HD} are not RES0
462	  as required by the architecture. The unadvertised HAFDBS
463	  implementation suffers from an additional erratum where hardware
464	  A/D updates can occur after a PTE has been marked invalid.
465
466	  The workaround forces KVM to explicitly set VTCR_EL2.HA to 0,
467	  which avoids enabling unadvertised hardware Access Flag management
468	  at stage-2.
469
470	  If unsure, say Y.
471
472config AMPERE_ERRATUM_AC04_CPU_23
473        bool "AmpereOne: AC04_CPU_23:  Failure to synchronize writes to HCR_EL2 may corrupt address translations."
474	default y
475	help
476	  This option adds an alternative code sequence to work around Ampere
477	  errata AC04_CPU_23 on AmpereOne.
478
479	  Updates to HCR_EL2 can rarely corrupt simultaneous translations for
480	  data addresses initiated by load/store instructions. Only
481	  instruction initiated translations are vulnerable, not translations
482	  from prefetches for example. A DSB before the store to HCR_EL2 is
483	  sufficient to prevent older instructions from hitting the window
484	  for corruption, and an ISB after is sufficient to prevent younger
485	  instructions from hitting the window for corruption.
486
487	  If unsure, say Y.
488
489config ARM64_WORKAROUND_CLEAN_CACHE
490	bool
491
492config ARM64_ERRATUM_826319
493	bool "Cortex-A53: 826319: System might deadlock if a write cannot complete until read data is accepted"
494	default y
495	select ARM64_WORKAROUND_CLEAN_CACHE
496	help
497	  This option adds an alternative code sequence to work around ARM
498	  erratum 826319 on Cortex-A53 parts up to r0p2 with an AMBA 4 ACE or
499	  AXI master interface and an L2 cache.
500
501	  If a Cortex-A53 uses an AMBA AXI4 ACE interface to other processors
502	  and is unable to accept a certain write via this interface, it will
503	  not progress on read data presented on the read data channel and the
504	  system can deadlock.
505
506	  The workaround promotes data cache clean instructions to
507	  data cache clean-and-invalidate.
508	  Please note that this does not necessarily enable the workaround,
509	  as it depends on the alternative framework, which will only patch
510	  the kernel if an affected CPU is detected.
511
512	  If unsure, say Y.
513
514config ARM64_ERRATUM_827319
515	bool "Cortex-A53: 827319: Data cache clean instructions might cause overlapping transactions to the interconnect"
516	default y
517	select ARM64_WORKAROUND_CLEAN_CACHE
518	help
519	  This option adds an alternative code sequence to work around ARM
520	  erratum 827319 on Cortex-A53 parts up to r0p2 with an AMBA 5 CHI
521	  master interface and an L2 cache.
522
523	  Under certain conditions this erratum can cause a clean line eviction
524	  to occur at the same time as another transaction to the same address
525	  on the AMBA 5 CHI interface, which can cause data corruption if the
526	  interconnect reorders the two transactions.
527
528	  The workaround promotes data cache clean instructions to
529	  data cache clean-and-invalidate.
530	  Please note that this does not necessarily enable the workaround,
531	  as it depends on the alternative framework, which will only patch
532	  the kernel if an affected CPU is detected.
533
534	  If unsure, say Y.
535
536config ARM64_ERRATUM_824069
537	bool "Cortex-A53: 824069: Cache line might not be marked as clean after a CleanShared snoop"
538	default y
539	select ARM64_WORKAROUND_CLEAN_CACHE
540	help
541	  This option adds an alternative code sequence to work around ARM
542	  erratum 824069 on Cortex-A53 parts up to r0p2 when it is connected
543	  to a coherent interconnect.
544
545	  If a Cortex-A53 processor is executing a store or prefetch for
546	  write instruction at the same time as a processor in another
547	  cluster is executing a cache maintenance operation to the same
548	  address, then this erratum might cause a clean cache line to be
549	  incorrectly marked as dirty.
550
551	  The workaround promotes data cache clean instructions to
552	  data cache clean-and-invalidate.
553	  Please note that this option does not necessarily enable the
554	  workaround, as it depends on the alternative framework, which will
555	  only patch the kernel if an affected CPU is detected.
556
557	  If unsure, say Y.
558
559config ARM64_ERRATUM_819472
560	bool "Cortex-A53: 819472: Store exclusive instructions might cause data corruption"
561	default y
562	select ARM64_WORKAROUND_CLEAN_CACHE
563	help
564	  This option adds an alternative code sequence to work around ARM
565	  erratum 819472 on Cortex-A53 parts up to r0p1 with an L2 cache
566	  present when it is connected to a coherent interconnect.
567
568	  If the processor is executing a load and store exclusive sequence at
569	  the same time as a processor in another cluster is executing a cache
570	  maintenance operation to the same address, then this erratum might
571	  cause data corruption.
572
573	  The workaround promotes data cache clean instructions to
574	  data cache clean-and-invalidate.
575	  Please note that this does not necessarily enable the workaround,
576	  as it depends on the alternative framework, which will only patch
577	  the kernel if an affected CPU is detected.
578
579	  If unsure, say Y.
580
581config ARM64_ERRATUM_832075
582	bool "Cortex-A57: 832075: possible deadlock on mixing exclusive memory accesses with device loads"
583	default y
584	help
585	  This option adds an alternative code sequence to work around ARM
586	  erratum 832075 on Cortex-A57 parts up to r1p2.
587
588	  Affected Cortex-A57 parts might deadlock when exclusive load/store
589	  instructions to Write-Back memory are mixed with Device loads.
590
591	  The workaround is to promote device loads to use Load-Acquire
592	  semantics.
593	  Please note that this does not necessarily enable the workaround,
594	  as it depends on the alternative framework, which will only patch
595	  the kernel if an affected CPU is detected.
596
597	  If unsure, say Y.
598
599config ARM64_ERRATUM_834220
600	bool "Cortex-A57: 834220: Stage 2 translation fault might be incorrectly reported in presence of a Stage 1 fault (rare)"
601	depends on KVM
602	help
603	  This option adds an alternative code sequence to work around ARM
604	  erratum 834220 on Cortex-A57 parts up to r1p2.
605
606	  Affected Cortex-A57 parts might report a Stage 2 translation
607	  fault as the result of a Stage 1 fault for load crossing a
608	  page boundary when there is a permission or device memory
609	  alignment fault at Stage 1 and a translation fault at Stage 2.
610
611	  The workaround is to verify that the Stage 1 translation
612	  doesn't generate a fault before handling the Stage 2 fault.
613	  Please note that this does not necessarily enable the workaround,
614	  as it depends on the alternative framework, which will only patch
615	  the kernel if an affected CPU is detected.
616
617	  If unsure, say N.
618
619config ARM64_ERRATUM_1742098
620	bool "Cortex-A57/A72: 1742098: ELR recorded incorrectly on interrupt taken between cryptographic instructions in a sequence"
621	depends on COMPAT
622	default y
623	help
624	  This option removes the AES hwcap for aarch32 user-space to
625	  workaround erratum 1742098 on Cortex-A57 and Cortex-A72.
626
627	  Affected parts may corrupt the AES state if an interrupt is
628	  taken between a pair of AES instructions. These instructions
629	  are only present if the cryptography extensions are present.
630	  All software should have a fallback implementation for CPUs
631	  that don't implement the cryptography extensions.
632
633	  If unsure, say Y.
634
635config ARM64_ERRATUM_845719
636	bool "Cortex-A53: 845719: a load might read incorrect data"
637	depends on COMPAT
638	default y
639	help
640	  This option adds an alternative code sequence to work around ARM
641	  erratum 845719 on Cortex-A53 parts up to r0p4.
642
643	  When running a compat (AArch32) userspace on an affected Cortex-A53
644	  part, a load at EL0 from a virtual address that matches the bottom 32
645	  bits of the virtual address used by a recent load at (AArch64) EL1
646	  might return incorrect data.
647
648	  The workaround is to write the contextidr_el1 register on exception
649	  return to a 32-bit task.
650	  Please note that this does not necessarily enable the workaround,
651	  as it depends on the alternative framework, which will only patch
652	  the kernel if an affected CPU is detected.
653
654	  If unsure, say Y.
655
656config ARM64_ERRATUM_843419
657	bool "Cortex-A53: 843419: A load or store might access an incorrect address"
658	default y
659	help
660	  This option links the kernel with '--fix-cortex-a53-843419' and
661	  enables PLT support to replace certain ADRP instructions, which can
662	  cause subsequent memory accesses to use an incorrect address on
663	  Cortex-A53 parts up to r0p4.
664
665	  If unsure, say Y.
666
667config ARM64_ERRATUM_1024718
668	bool "Cortex-A55: 1024718: Update of DBM/AP bits without break before make might result in incorrect update"
669	default y
670	help
671	  This option adds a workaround for ARM Cortex-A55 Erratum 1024718.
672
673	  Affected Cortex-A55 cores (all revisions) could cause incorrect
674	  update of the hardware dirty bit when the DBM/AP bits are updated
675	  without a break-before-make. The workaround is to disable the usage
676	  of hardware DBM locally on the affected cores. CPUs not affected by
677	  this erratum will continue to use the feature.
678
679	  If unsure, say Y.
680
681config ARM64_ERRATUM_1418040
682	bool "Cortex-A76/Neoverse-N1: MRC read following MRRC read of specific Generic Timer in AArch32 might give incorrect result"
683	default y
684	depends on COMPAT
685	help
686	  This option adds a workaround for ARM Cortex-A76/Neoverse-N1
687	  errata 1188873 and 1418040.
688
689	  Affected Cortex-A76/Neoverse-N1 cores (r0p0 to r3p1) could
690	  cause register corruption when accessing the timer registers
691	  from AArch32 userspace.
692
693	  If unsure, say Y.
694
695config ARM64_WORKAROUND_SPECULATIVE_AT
696	bool
697
698config ARM64_ERRATUM_1165522
699	bool "Cortex-A76: 1165522: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
700	default y
701	select ARM64_WORKAROUND_SPECULATIVE_AT
702	help
703	  This option adds a workaround for ARM Cortex-A76 erratum 1165522.
704
705	  Affected Cortex-A76 cores (r0p0, r1p0, r2p0) could end-up with
706	  corrupted TLBs by speculating an AT instruction during a guest
707	  context switch.
708
709	  If unsure, say Y.
710
711config ARM64_ERRATUM_1319367
712	bool "Cortex-A57/A72: 1319537: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
713	default y
714	select ARM64_WORKAROUND_SPECULATIVE_AT
715	help
716	  This option adds work arounds for ARM Cortex-A57 erratum 1319537
717	  and A72 erratum 1319367
718
719	  Cortex-A57 and A72 cores could end-up with corrupted TLBs by
720	  speculating an AT instruction during a guest context switch.
721
722	  If unsure, say Y.
723
724config ARM64_ERRATUM_1530923
725	bool "Cortex-A55: 1530923: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
726	default y
727	select ARM64_WORKAROUND_SPECULATIVE_AT
728	help
729	  This option adds a workaround for ARM Cortex-A55 erratum 1530923.
730
731	  Affected Cortex-A55 cores (r0p0, r0p1, r1p0, r2p0) could end-up with
732	  corrupted TLBs by speculating an AT instruction during a guest
733	  context switch.
734
735	  If unsure, say Y.
736
737config ARM64_WORKAROUND_REPEAT_TLBI
738	bool
739
740config ARM64_ERRATUM_2441007
741	bool "Cortex-A55: Completion of affected memory accesses might not be guaranteed by completion of a TLBI (rare)"
742	select ARM64_WORKAROUND_REPEAT_TLBI
743	help
744	  This option adds a workaround for ARM Cortex-A55 erratum #2441007.
745
746	  Under very rare circumstances, affected Cortex-A55 CPUs
747	  may not handle a race between a break-before-make sequence on one
748	  CPU, and another CPU accessing the same page. This could allow a
749	  store to a page that has been unmapped.
750
751	  Work around this by adding the affected CPUs to the list that needs
752	  TLB sequences to be done twice.
753
754	  If unsure, say N.
755
756config ARM64_ERRATUM_1286807
757	bool "Cortex-A76: Modification of the translation table for a virtual address might lead to read-after-read ordering violation (rare)"
758	select ARM64_WORKAROUND_REPEAT_TLBI
759	help
760	  This option adds a workaround for ARM Cortex-A76 erratum 1286807.
761
762	  On the affected Cortex-A76 cores (r0p0 to r3p0), if a virtual
763	  address for a cacheable mapping of a location is being
764	  accessed by a core while another core is remapping the virtual
765	  address to a new physical page using the recommended
766	  break-before-make sequence, then under very rare circumstances
767	  TLBI+DSB completes before a read using the translation being
768	  invalidated has been observed by other observers. The
769	  workaround repeats the TLBI+DSB operation.
770
771	  If unsure, say N.
772
773config ARM64_ERRATUM_1463225
774	bool "Cortex-A76: Software Step might prevent interrupt recognition"
775	default y
776	help
777	  This option adds a workaround for Arm Cortex-A76 erratum 1463225.
778
779	  On the affected Cortex-A76 cores (r0p0 to r3p1), software stepping
780	  of a system call instruction (SVC) can prevent recognition of
781	  subsequent interrupts when software stepping is disabled in the
782	  exception handler of the system call and either kernel debugging
783	  is enabled or VHE is in use.
784
785	  Work around the erratum by triggering a dummy step exception
786	  when handling a system call from a task that is being stepped
787	  in a VHE configuration of the kernel.
788
789	  If unsure, say Y.
790
791config ARM64_ERRATUM_1542419
792	bool "Neoverse-N1: workaround mis-ordering of instruction fetches (rare)"
793	help
794	  This option adds a workaround for ARM Neoverse-N1 erratum
795	  1542419.
796
797	  Affected Neoverse-N1 cores could execute a stale instruction when
798	  modified by another CPU. The workaround depends on a firmware
799	  counterpart.
800
801	  Workaround the issue by hiding the DIC feature from EL0. This
802	  forces user-space to perform cache maintenance.
803
804	  If unsure, say N.
805
806config ARM64_ERRATUM_1508412
807	bool "Cortex-A77: 1508412: workaround deadlock on sequence of NC/Device load and store exclusive or PAR read"
808	default y
809	help
810	  This option adds a workaround for Arm Cortex-A77 erratum 1508412.
811
812	  Affected Cortex-A77 cores (r0p0, r1p0) could deadlock on a sequence
813	  of a store-exclusive or read of PAR_EL1 and a load with device or
814	  non-cacheable memory attributes. The workaround depends on a firmware
815	  counterpart.
816
817	  KVM guests must also have the workaround implemented or they can
818	  deadlock the system.
819
820	  Work around the issue by inserting DMB SY barriers around PAR_EL1
821	  register reads and warning KVM users. The DMB barrier is sufficient
822	  to prevent a speculative PAR_EL1 read.
823
824	  If unsure, say Y.
825
826config ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
827	bool
828
829config ARM64_ERRATUM_2051678
830	bool "Cortex-A510: 2051678: disable Hardware Update of the page table dirty bit"
831	default y
832	help
833	  This options adds the workaround for ARM Cortex-A510 erratum ARM64_ERRATUM_2051678.
834	  Affected Cortex-A510 might not respect the ordering rules for
835	  hardware update of the page table's dirty bit. The workaround
836	  is to not enable the feature on affected CPUs.
837
838	  If unsure, say Y.
839
840config ARM64_ERRATUM_2077057
841	bool "Cortex-A510: 2077057: workaround software-step corrupting SPSR_EL2"
842	default y
843	help
844	  This option adds the workaround for ARM Cortex-A510 erratum 2077057.
845	  Affected Cortex-A510 may corrupt SPSR_EL2 when the a step exception is
846	  expected, but a Pointer Authentication trap is taken instead. The
847	  erratum causes SPSR_EL1 to be copied to SPSR_EL2, which could allow
848	  EL1 to cause a return to EL2 with a guest controlled ELR_EL2.
849
850	  This can only happen when EL2 is stepping EL1.
851
852	  When these conditions occur, the SPSR_EL2 value is unchanged from the
853	  previous guest entry, and can be restored from the in-memory copy.
854
855	  If unsure, say Y.
856
857config ARM64_ERRATUM_2658417
858	bool "Cortex-A510: 2658417: remove BF16 support due to incorrect result"
859	default y
860	help
861	  This option adds the workaround for ARM Cortex-A510 erratum 2658417.
862	  Affected Cortex-A510 (r0p0 to r1p1) may produce the wrong result for
863	  BFMMLA or VMMLA instructions in rare circumstances when a pair of
864	  A510 CPUs are using shared neon hardware. As the sharing is not
865	  discoverable by the kernel, hide the BF16 HWCAP to indicate that
866	  user-space should not be using these instructions.
867
868	  If unsure, say Y.
869
870config ARM64_ERRATUM_2119858
871	bool "Cortex-A710/X2: 2119858: workaround TRBE overwriting trace data in FILL mode"
872	default y
873	depends on CORESIGHT_TRBE
874	select ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
875	help
876	  This option adds the workaround for ARM Cortex-A710/X2 erratum 2119858.
877
878	  Affected Cortex-A710/X2 cores could overwrite up to 3 cache lines of trace
879	  data at the base of the buffer (pointed to by TRBASER_EL1) in FILL mode in
880	  the event of a WRAP event.
881
882	  Work around the issue by always making sure we move the TRBPTR_EL1 by
883	  256 bytes before enabling the buffer and filling the first 256 bytes of
884	  the buffer with ETM ignore packets upon disabling.
885
886	  If unsure, say Y.
887
888config ARM64_ERRATUM_2139208
889	bool "Neoverse-N2: 2139208: workaround TRBE overwriting trace data in FILL mode"
890	default y
891	depends on CORESIGHT_TRBE
892	select ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
893	help
894	  This option adds the workaround for ARM Neoverse-N2 erratum 2139208.
895
896	  Affected Neoverse-N2 cores could overwrite up to 3 cache lines of trace
897	  data at the base of the buffer (pointed to by TRBASER_EL1) in FILL mode in
898	  the event of a WRAP event.
899
900	  Work around the issue by always making sure we move the TRBPTR_EL1 by
901	  256 bytes before enabling the buffer and filling the first 256 bytes of
902	  the buffer with ETM ignore packets upon disabling.
903
904	  If unsure, say Y.
905
906config ARM64_WORKAROUND_TSB_FLUSH_FAILURE
907	bool
908
909config ARM64_ERRATUM_2054223
910	bool "Cortex-A710: 2054223: workaround TSB instruction failing to flush trace"
911	default y
912	select ARM64_WORKAROUND_TSB_FLUSH_FAILURE
913	help
914	  Enable workaround for ARM Cortex-A710 erratum 2054223
915
916	  Affected cores may fail to flush the trace data on a TSB instruction, when
917	  the PE is in trace prohibited state. This will cause losing a few bytes
918	  of the trace cached.
919
920	  Workaround is to issue two TSB consecutively on affected cores.
921
922	  If unsure, say Y.
923
924config ARM64_ERRATUM_2067961
925	bool "Neoverse-N2: 2067961: workaround TSB instruction failing to flush trace"
926	default y
927	select ARM64_WORKAROUND_TSB_FLUSH_FAILURE
928	help
929	  Enable workaround for ARM Neoverse-N2 erratum 2067961
930
931	  Affected cores may fail to flush the trace data on a TSB instruction, when
932	  the PE is in trace prohibited state. This will cause losing a few bytes
933	  of the trace cached.
934
935	  Workaround is to issue two TSB consecutively on affected cores.
936
937	  If unsure, say Y.
938
939config ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE
940	bool
941
942config ARM64_ERRATUM_2253138
943	bool "Neoverse-N2: 2253138: workaround TRBE writing to address out-of-range"
944	depends on CORESIGHT_TRBE
945	default y
946	select ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE
947	help
948	  This option adds the workaround for ARM Neoverse-N2 erratum 2253138.
949
950	  Affected Neoverse-N2 cores might write to an out-of-range address, not reserved
951	  for TRBE. Under some conditions, the TRBE might generate a write to the next
952	  virtually addressed page following the last page of the TRBE address space
953	  (i.e., the TRBLIMITR_EL1.LIMIT), instead of wrapping around to the base.
954
955	  Work around this in the driver by always making sure that there is a
956	  page beyond the TRBLIMITR_EL1.LIMIT, within the space allowed for the TRBE.
957
958	  If unsure, say Y.
959
960config ARM64_ERRATUM_2224489
961	bool "Cortex-A710/X2: 2224489: workaround TRBE writing to address out-of-range"
962	depends on CORESIGHT_TRBE
963	default y
964	select ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE
965	help
966	  This option adds the workaround for ARM Cortex-A710/X2 erratum 2224489.
967
968	  Affected Cortex-A710/X2 cores might write to an out-of-range address, not reserved
969	  for TRBE. Under some conditions, the TRBE might generate a write to the next
970	  virtually addressed page following the last page of the TRBE address space
971	  (i.e., the TRBLIMITR_EL1.LIMIT), instead of wrapping around to the base.
972
973	  Work around this in the driver by always making sure that there is a
974	  page beyond the TRBLIMITR_EL1.LIMIT, within the space allowed for the TRBE.
975
976	  If unsure, say Y.
977
978config ARM64_ERRATUM_2441009
979	bool "Cortex-A510: Completion of affected memory accesses might not be guaranteed by completion of a TLBI (rare)"
980	select ARM64_WORKAROUND_REPEAT_TLBI
981	help
982	  This option adds a workaround for ARM Cortex-A510 erratum #2441009.
983
984	  Under very rare circumstances, affected Cortex-A510 CPUs
985	  may not handle a race between a break-before-make sequence on one
986	  CPU, and another CPU accessing the same page. This could allow a
987	  store to a page that has been unmapped.
988
989	  Work around this by adding the affected CPUs to the list that needs
990	  TLB sequences to be done twice.
991
992	  If unsure, say N.
993
994config ARM64_ERRATUM_2064142
995	bool "Cortex-A510: 2064142: workaround TRBE register writes while disabled"
996	depends on CORESIGHT_TRBE
997	default y
998	help
999	  This option adds the workaround for ARM Cortex-A510 erratum 2064142.
1000
1001	  Affected Cortex-A510 core might fail to write into system registers after the
1002	  TRBE has been disabled. Under some conditions after the TRBE has been disabled
1003	  writes into TRBE registers TRBLIMITR_EL1, TRBPTR_EL1, TRBBASER_EL1, TRBSR_EL1,
1004	  and TRBTRG_EL1 will be ignored and will not be effected.
1005
1006	  Work around this in the driver by executing TSB CSYNC and DSB after collection
1007	  is stopped and before performing a system register write to one of the affected
1008	  registers.
1009
1010	  If unsure, say Y.
1011
1012config ARM64_ERRATUM_2038923
1013	bool "Cortex-A510: 2038923: workaround TRBE corruption with enable"
1014	depends on CORESIGHT_TRBE
1015	default y
1016	help
1017	  This option adds the workaround for ARM Cortex-A510 erratum 2038923.
1018
1019	  Affected Cortex-A510 core might cause an inconsistent view on whether trace is
1020	  prohibited within the CPU. As a result, the trace buffer or trace buffer state
1021	  might be corrupted. This happens after TRBE buffer has been enabled by setting
1022	  TRBLIMITR_EL1.E, followed by just a single context synchronization event before
1023	  execution changes from a context, in which trace is prohibited to one where it
1024	  isn't, or vice versa. In these mentioned conditions, the view of whether trace
1025	  is prohibited is inconsistent between parts of the CPU, and the trace buffer or
1026	  the trace buffer state might be corrupted.
1027
1028	  Work around this in the driver by preventing an inconsistent view of whether the
1029	  trace is prohibited or not based on TRBLIMITR_EL1.E by immediately following a
1030	  change to TRBLIMITR_EL1.E with at least one ISB instruction before an ERET, or
1031	  two ISB instructions if no ERET is to take place.
1032
1033	  If unsure, say Y.
1034
1035config ARM64_ERRATUM_1902691
1036	bool "Cortex-A510: 1902691: workaround TRBE trace corruption"
1037	depends on CORESIGHT_TRBE
1038	default y
1039	help
1040	  This option adds the workaround for ARM Cortex-A510 erratum 1902691.
1041
1042	  Affected Cortex-A510 core might cause trace data corruption, when being written
1043	  into the memory. Effectively TRBE is broken and hence cannot be used to capture
1044	  trace data.
1045
1046	  Work around this problem in the driver by just preventing TRBE initialization on
1047	  affected cpus. The firmware must have disabled the access to TRBE for the kernel
1048	  on such implementations. This will cover the kernel for any firmware that doesn't
1049	  do this already.
1050
1051	  If unsure, say Y.
1052
1053config ARM64_ERRATUM_2457168
1054	bool "Cortex-A510: 2457168: workaround for AMEVCNTR01 incrementing incorrectly"
1055	depends on ARM64_AMU_EXTN
1056	default y
1057	help
1058	  This option adds the workaround for ARM Cortex-A510 erratum 2457168.
1059
1060	  The AMU counter AMEVCNTR01 (constant counter) should increment at the same rate
1061	  as the system counter. On affected Cortex-A510 cores AMEVCNTR01 increments
1062	  incorrectly giving a significantly higher output value.
1063
1064	  Work around this problem by returning 0 when reading the affected counter in
1065	  key locations that results in disabling all users of this counter. This effect
1066	  is the same to firmware disabling affected counters.
1067
1068	  If unsure, say Y.
1069
1070config ARM64_ERRATUM_2645198
1071	bool "Cortex-A715: 2645198: Workaround possible [ESR|FAR]_ELx corruption"
1072	default y
1073	help
1074	  This option adds the workaround for ARM Cortex-A715 erratum 2645198.
1075
1076	  If a Cortex-A715 cpu sees a page mapping permissions change from executable
1077	  to non-executable, it may corrupt the ESR_ELx and FAR_ELx registers on the
1078	  next instruction abort caused by permission fault.
1079
1080	  Only user-space does executable to non-executable permission transition via
1081	  mprotect() system call. Workaround the problem by doing a break-before-make
1082	  TLB invalidation, for all changes to executable user space mappings.
1083
1084	  If unsure, say Y.
1085
1086config ARM64_WORKAROUND_SPECULATIVE_UNPRIV_LOAD
1087	bool
1088
1089config ARM64_ERRATUM_2966298
1090	bool "Cortex-A520: 2966298: workaround for speculatively executed unprivileged load"
1091	select ARM64_WORKAROUND_SPECULATIVE_UNPRIV_LOAD
1092	default y
1093	help
1094	  This option adds the workaround for ARM Cortex-A520 erratum 2966298.
1095
1096	  On an affected Cortex-A520 core, a speculatively executed unprivileged
1097	  load might leak data from a privileged level via a cache side channel.
1098
1099	  Work around this problem by executing a TLBI before returning to EL0.
1100
1101	  If unsure, say Y.
1102
1103config ARM64_ERRATUM_3117295
1104	bool "Cortex-A510: 3117295: workaround for speculatively executed unprivileged load"
1105	select ARM64_WORKAROUND_SPECULATIVE_UNPRIV_LOAD
1106	default y
1107	help
1108	  This option adds the workaround for ARM Cortex-A510 erratum 3117295.
1109
1110	  On an affected Cortex-A510 core, a speculatively executed unprivileged
1111	  load might leak data from a privileged level via a cache side channel.
1112
1113	  Work around this problem by executing a TLBI before returning to EL0.
1114
1115	  If unsure, say Y.
1116
1117config ARM64_ERRATUM_3194386
1118	bool "Cortex-*/Neoverse-*: workaround for MSR SSBS not self-synchronizing"
1119	default y
1120	help
1121	  This option adds the workaround for the following errata:
1122
1123	  * ARM Cortex-A76 erratum 3324349
1124	  * ARM Cortex-A77 erratum 3324348
1125	  * ARM Cortex-A78 erratum 3324344
1126	  * ARM Cortex-A78C erratum 3324346
1127	  * ARM Cortex-A78C erratum 3324347
1128	  * ARM Cortex-A710 erratam 3324338
1129	  * ARM Cortex-A715 errartum 3456084
1130	  * ARM Cortex-A720 erratum 3456091
1131	  * ARM Cortex-A725 erratum 3456106
1132	  * ARM Cortex-X1 erratum 3324344
1133	  * ARM Cortex-X1C erratum 3324346
1134	  * ARM Cortex-X2 erratum 3324338
1135	  * ARM Cortex-X3 erratum 3324335
1136	  * ARM Cortex-X4 erratum 3194386
1137	  * ARM Cortex-X925 erratum 3324334
1138	  * ARM Neoverse-N1 erratum 3324349
1139	  * ARM Neoverse N2 erratum 3324339
1140	  * ARM Neoverse-N3 erratum 3456111
1141	  * ARM Neoverse-V1 erratum 3324341
1142	  * ARM Neoverse V2 erratum 3324336
1143	  * ARM Neoverse-V3 erratum 3312417
1144	  * ARM Neoverse-V3AE erratum 3312417
1145
1146	  On affected cores "MSR SSBS, #0" instructions may not affect
1147	  subsequent speculative instructions, which may permit unexepected
1148	  speculative store bypassing.
1149
1150	  Work around this problem by placing a Speculation Barrier (SB) or
1151	  Instruction Synchronization Barrier (ISB) after kernel changes to
1152	  SSBS. The presence of the SSBS special-purpose register is hidden
1153	  from hwcaps and EL0 reads of ID_AA64PFR1_EL1, such that userspace
1154	  will use the PR_SPEC_STORE_BYPASS prctl to change SSBS.
1155
1156	  If unsure, say Y.
1157
1158config ARM64_ERRATUM_4311569
1159	bool "SI L1: 4311569: workaround for premature CMO completion erratum"
1160	default y
1161	help
1162	  This option adds the workaround for ARM SI L1 erratum 4311569.
1163
1164	  The erratum of SI L1 can cause an early response to a combined write
1165	  and cache maintenance operation (WR+CMO) before the operation is fully
1166	  completed to the Point of Serialization (POS).
1167	  This can result in a non-I/O coherent agent observing stale data,
1168	  potentially leading to system instability or incorrect behavior.
1169
1170	  Enabling this option implements a software workaround by inserting a
1171	  second loop of Cache Maintenance Operation (CMO) immediately following the
1172	  end of function to do CMOs. This ensures that the data is correctly serialized
1173	  before the buffer is handed off to a non-coherent agent.
1174
1175	  If unsure, say Y.
1176
1177config CAVIUM_ERRATUM_22375
1178	bool "Cavium erratum 22375, 24313"
1179	default y
1180	help
1181	  Enable workaround for errata 22375 and 24313.
1182
1183	  This implements two gicv3-its errata workarounds for ThunderX. Both
1184	  with a small impact affecting only ITS table allocation.
1185
1186	    erratum 22375: only alloc 8MB table size
1187	    erratum 24313: ignore memory access type
1188
1189	  The fixes are in ITS initialization and basically ignore memory access
1190	  type and table size provided by the TYPER and BASER registers.
1191
1192	  If unsure, say Y.
1193
1194config CAVIUM_ERRATUM_23144
1195	bool "Cavium erratum 23144: ITS SYNC hang on dual socket system"
1196	depends on NUMA
1197	default y
1198	help
1199	  ITS SYNC command hang for cross node io and collections/cpu mapping.
1200
1201	  If unsure, say Y.
1202
1203config CAVIUM_ERRATUM_23154
1204	bool "Cavium errata 23154 and 38545: GICv3 lacks HW synchronisation"
1205	default y
1206	help
1207	  The ThunderX GICv3 implementation requires a modified version for
1208	  reading the IAR status to ensure data synchronization
1209	  (access to icc_iar1_el1 is not sync'ed before and after).
1210
1211	  It also suffers from erratum 38545 (also present on Marvell's
1212	  OcteonTX and OcteonTX2), resulting in deactivated interrupts being
1213	  spuriously presented to the CPU interface.
1214
1215	  If unsure, say Y.
1216
1217config CAVIUM_ERRATUM_27456
1218	bool "Cavium erratum 27456: Broadcast TLBI instructions may cause icache corruption"
1219	default y
1220	help
1221	  On ThunderX T88 pass 1.x through 2.1 parts, broadcast TLBI
1222	  instructions may cause the icache to become corrupted if it
1223	  contains data for a non-current ASID.  The fix is to
1224	  invalidate the icache when changing the mm context.
1225
1226	  If unsure, say Y.
1227
1228config CAVIUM_ERRATUM_30115
1229	bool "Cavium erratum 30115: Guest may disable interrupts in host"
1230	default y
1231	help
1232	  On ThunderX T88 pass 1.x through 2.2, T81 pass 1.0 through
1233	  1.2, and T83 Pass 1.0, KVM guest execution may disable
1234	  interrupts in host. Trapping both GICv3 group-0 and group-1
1235	  accesses sidesteps the issue.
1236
1237	  If unsure, say Y.
1238
1239config CAVIUM_TX2_ERRATUM_219
1240	bool "Cavium ThunderX2 erratum 219: PRFM between TTBR change and ISB fails"
1241	default y
1242	help
1243	  On Cavium ThunderX2, a load, store or prefetch instruction between a
1244	  TTBR update and the corresponding context synchronizing operation can
1245	  cause a spurious Data Abort to be delivered to any hardware thread in
1246	  the CPU core.
1247
1248	  Work around the issue by avoiding the problematic code sequence and
1249	  trapping KVM guest TTBRx_EL1 writes to EL2 when SMT is enabled. The
1250	  trap handler performs the corresponding register access, skips the
1251	  instruction and ensures context synchronization by virtue of the
1252	  exception return.
1253
1254	  If unsure, say Y.
1255
1256config FUJITSU_ERRATUM_010001
1257	bool "Fujitsu-A64FX erratum E#010001: Undefined fault may occur wrongly"
1258	default y
1259	help
1260	  This option adds a workaround for Fujitsu-A64FX erratum E#010001.
1261	  On some variants of the Fujitsu-A64FX cores ver(1.0, 1.1), memory
1262	  accesses may cause undefined fault (Data abort, DFSC=0b111111).
1263	  This fault occurs under a specific hardware condition when a
1264	  load/store instruction performs an address translation using:
1265	  case-1  TTBR0_EL1 with TCR_EL1.NFD0 == 1.
1266	  case-2  TTBR0_EL2 with TCR_EL2.NFD0 == 1.
1267	  case-3  TTBR1_EL1 with TCR_EL1.NFD1 == 1.
1268	  case-4  TTBR1_EL2 with TCR_EL2.NFD1 == 1.
1269
1270	  The workaround is to ensure these bits are clear in TCR_ELx.
1271	  The workaround only affects the Fujitsu-A64FX.
1272
1273	  If unsure, say Y.
1274
1275config HISILICON_ERRATUM_161600802
1276	bool "Hip07 161600802: Erroneous redistributor VLPI base"
1277	default y
1278	help
1279	  The HiSilicon Hip07 SoC uses the wrong redistributor base
1280	  when issued ITS commands such as VMOVP and VMAPP, and requires
1281	  a 128kB offset to be applied to the target address in this commands.
1282
1283	  If unsure, say Y.
1284
1285config HISILICON_ERRATUM_162100801
1286	bool "Hip09 162100801 erratum support"
1287	default y
1288	help
1289	  When enabling GICv4.1 in hip09, VMAPP will fail to clear some caches
1290	  during unmapping operation, which will cause some vSGIs lost.
1291	  To fix the issue, invalidate related vPE cache through GICR_INVALLR
1292	  after VMOVP.
1293
1294	  If unsure, say Y.
1295
1296config QCOM_FALKOR_ERRATUM_1003
1297	bool "Falkor E1003: Incorrect translation due to ASID change"
1298	default y
1299	help
1300	  On Falkor v1, an incorrect ASID may be cached in the TLB when ASID
1301	  and BADDR are changed together in TTBRx_EL1. Since we keep the ASID
1302	  in TTBR1_EL1, this situation only occurs in the entry trampoline and
1303	  then only for entries in the walk cache, since the leaf translation
1304	  is unchanged. Work around the erratum by invalidating the walk cache
1305	  entries for the trampoline before entering the kernel proper.
1306
1307config QCOM_FALKOR_ERRATUM_1009
1308	bool "Falkor E1009: Prematurely complete a DSB after a TLBI"
1309	default y
1310	select ARM64_WORKAROUND_REPEAT_TLBI
1311	help
1312	  On Falkor v1, the CPU may prematurely complete a DSB following a
1313	  TLBI xxIS invalidate maintenance operation. Repeat the TLBI operation
1314	  one more time to fix the issue.
1315
1316	  If unsure, say Y.
1317
1318config QCOM_QDF2400_ERRATUM_0065
1319	bool "QDF2400 E0065: Incorrect GITS_TYPER.ITT_Entry_size"
1320	default y
1321	help
1322	  On Qualcomm Datacenter Technologies QDF2400 SoC, ITS hardware reports
1323	  ITE size incorrectly. The GITS_TYPER.ITT_Entry_size field should have
1324	  been indicated as 16Bytes (0xf), not 8Bytes (0x7).
1325
1326	  If unsure, say Y.
1327
1328config QCOM_FALKOR_ERRATUM_E1041
1329	bool "Falkor E1041: Speculative instruction fetches might cause errant memory access"
1330	default y
1331	help
1332	  Falkor CPU may speculatively fetch instructions from an improper
1333	  memory location when MMU translation is changed from SCTLR_ELn[M]=1
1334	  to SCTLR_ELn[M]=0. Prefix an ISB instruction to fix the problem.
1335
1336	  If unsure, say Y.
1337
1338config NVIDIA_CARMEL_CNP_ERRATUM
1339	bool "NVIDIA Carmel CNP: CNP on Carmel semantically different than ARM cores"
1340	default y
1341	help
1342	  If CNP is enabled on Carmel cores, non-sharable TLBIs on a core will not
1343	  invalidate shared TLB entries installed by a different core, as it would
1344	  on standard ARM cores.
1345
1346	  If unsure, say Y.
1347
1348config ROCKCHIP_ERRATUM_3568002
1349	bool "Rockchip 3568002: GIC600 can not access physical addresses higher than 4GB"
1350	default y
1351	help
1352	  The Rockchip RK3566 and RK3568 GIC600 SoC integrations have AXI
1353	  addressing limited to the first 32bit of physical address space.
1354
1355	  If unsure, say Y.
1356
1357config ROCKCHIP_ERRATUM_3588001
1358	bool "Rockchip 3588001: GIC600 can not support shareability attributes"
1359	default y
1360	help
1361	  The Rockchip RK3588 GIC600 SoC integration does not support ACE/ACE-lite.
1362	  This means, that its sharability feature may not be used, even though it
1363	  is supported by the IP itself.
1364
1365	  If unsure, say Y.
1366
1367config SOCIONEXT_SYNQUACER_PREITS
1368	bool "Socionext Synquacer: Workaround for GICv3 pre-ITS"
1369	default y
1370	help
1371	  Socionext Synquacer SoCs implement a separate h/w block to generate
1372	  MSI doorbell writes with non-zero values for the device ID.
1373
1374	  If unsure, say Y.
1375
1376endmenu # "ARM errata workarounds via the alternatives framework"
1377
1378choice
1379	prompt "Page size"
1380	default ARM64_4K_PAGES
1381	help
1382	  Page size (translation granule) configuration.
1383
1384config ARM64_4K_PAGES
1385	bool "4KB"
1386	select HAVE_PAGE_SIZE_4KB
1387	help
1388	  This feature enables 4KB pages support.
1389
1390config ARM64_16K_PAGES
1391	bool "16KB"
1392	select HAVE_PAGE_SIZE_16KB
1393	help
1394	  The system will use 16KB pages support. AArch32 emulation
1395	  requires applications compiled with 16K (or a multiple of 16K)
1396	  aligned segments.
1397
1398config ARM64_64K_PAGES
1399	bool "64KB"
1400	select HAVE_PAGE_SIZE_64KB
1401	help
1402	  This feature enables 64KB pages support (4KB by default)
1403	  allowing only two levels of page tables and faster TLB
1404	  look-up. AArch32 emulation requires applications compiled
1405	  with 64K aligned segments.
1406
1407endchoice
1408
1409choice
1410	prompt "Virtual address space size"
1411	default ARM64_VA_BITS_52
1412	help
1413	  Allows choosing one of multiple possible virtual address
1414	  space sizes. The level of translation table is determined by
1415	  a combination of page size and virtual address space size.
1416
1417config ARM64_VA_BITS_36
1418	bool "36-bit" if EXPERT
1419	depends on PAGE_SIZE_16KB
1420
1421config ARM64_VA_BITS_39
1422	bool "39-bit"
1423	depends on PAGE_SIZE_4KB
1424
1425config ARM64_VA_BITS_42
1426	bool "42-bit"
1427	depends on PAGE_SIZE_64KB
1428
1429config ARM64_VA_BITS_47
1430	bool "47-bit"
1431	depends on PAGE_SIZE_16KB
1432
1433config ARM64_VA_BITS_48
1434	bool "48-bit"
1435
1436config ARM64_VA_BITS_52
1437	bool "52-bit"
1438	help
1439	  Enable 52-bit virtual addressing for userspace when explicitly
1440	  requested via a hint to mmap(). The kernel will also use 52-bit
1441	  virtual addresses for its own mappings (provided HW support for
1442	  this feature is available, otherwise it reverts to 48-bit).
1443
1444	  NOTE: Enabling 52-bit virtual addressing in conjunction with
1445	  ARMv8.3 Pointer Authentication will result in the PAC being
1446	  reduced from 7 bits to 3 bits, which may have a significant
1447	  impact on its susceptibility to brute-force attacks.
1448
1449	  If unsure, select 48-bit virtual addressing instead.
1450
1451endchoice
1452
1453config ARM64_FORCE_52BIT
1454	bool "Force 52-bit virtual addresses for userspace"
1455	depends on ARM64_VA_BITS_52 && EXPERT
1456	help
1457	  For systems with 52-bit userspace VAs enabled, the kernel will attempt
1458	  to maintain compatibility with older software by providing 48-bit VAs
1459	  unless a hint is supplied to mmap.
1460
1461	  This configuration option disables the 48-bit compatibility logic, and
1462	  forces all userspace addresses to be 52-bit on HW that supports it. One
1463	  should only enable this configuration option for stress testing userspace
1464	  memory management code. If unsure say N here.
1465
1466config ARM64_VA_BITS
1467	int
1468	default 36 if ARM64_VA_BITS_36
1469	default 39 if ARM64_VA_BITS_39
1470	default 42 if ARM64_VA_BITS_42
1471	default 47 if ARM64_VA_BITS_47
1472	default 48 if ARM64_VA_BITS_48
1473	default 52 if ARM64_VA_BITS_52
1474
1475choice
1476	prompt "Physical address space size"
1477	default ARM64_PA_BITS_48
1478	help
1479	  Choose the maximum physical address range that the kernel will
1480	  support.
1481
1482config ARM64_PA_BITS_48
1483	bool "48-bit"
1484	depends on ARM64_64K_PAGES || !ARM64_VA_BITS_52
1485
1486config ARM64_PA_BITS_52
1487	bool "52-bit"
1488	depends on ARM64_64K_PAGES || ARM64_VA_BITS_52
1489	help
1490	  Enable support for a 52-bit physical address space, introduced as
1491	  part of the ARMv8.2-LPA extension.
1492
1493	  With this enabled, the kernel will also continue to work on CPUs that
1494	  do not support ARMv8.2-LPA, but with some added memory overhead (and
1495	  minor performance overhead).
1496
1497endchoice
1498
1499config ARM64_PA_BITS
1500	int
1501	default 48 if ARM64_PA_BITS_48
1502	default 52 if ARM64_PA_BITS_52
1503
1504config ARM64_LPA2
1505	def_bool y
1506	depends on ARM64_PA_BITS_52 && !ARM64_64K_PAGES
1507
1508choice
1509	prompt "Endianness"
1510	default CPU_LITTLE_ENDIAN
1511	help
1512	  Select the endianness of data accesses performed by the CPU. Userspace
1513	  applications will need to be compiled and linked for the endianness
1514	  that is selected here.
1515
1516config CPU_BIG_ENDIAN
1517	bool "Build big-endian kernel"
1518	depends on BROKEN
1519	help
1520	  Say Y if you plan on running a kernel with a big-endian userspace.
1521
1522config CPU_LITTLE_ENDIAN
1523	bool "Build little-endian kernel"
1524	help
1525	  Say Y if you plan on running a kernel with a little-endian userspace.
1526	  This is usually the case for distributions targeting arm64.
1527
1528endchoice
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
1573config HW_PERF_EVENTS
1574	def_bool y
1575	depends on ARM_PMU
1576
1577# Supported by clang >= 7.0 or GCC >= 12.0.0
1578config CC_HAVE_SHADOW_CALL_STACK
1579	def_bool $(cc-option, -fsanitize=shadow-call-stack -ffixed-x18)
1580
1581config PARAVIRT
1582	bool "Enable paravirtualization code"
1583	help
1584	  This changes the kernel so it can modify itself when it is run
1585	  under a hypervisor, potentially improving performance significantly
1586	  over full virtualization.
1587
1588config PARAVIRT_TIME_ACCOUNTING
1589	bool "Paravirtual steal time accounting"
1590	select PARAVIRT
1591	help
1592	  Select this option to enable fine granularity task steal time
1593	  accounting. Time spent executing other tasks in parallel with
1594	  the current vCPU is discounted from the vCPU power. To account for
1595	  that, there can be a small performance impact.
1596
1597	  If in doubt, say N here.
1598
1599config ARCH_SUPPORTS_KEXEC
1600	def_bool PM_SLEEP_SMP
1601
1602config ARCH_SUPPORTS_KEXEC_FILE
1603	def_bool y
1604
1605config ARCH_SELECTS_KEXEC_FILE
1606	def_bool y
1607	depends on KEXEC_FILE
1608	select HAVE_IMA_KEXEC if IMA
1609
1610config ARCH_SUPPORTS_KEXEC_SIG
1611	def_bool y
1612
1613config ARCH_SUPPORTS_KEXEC_IMAGE_VERIFY_SIG
1614	def_bool y
1615
1616config ARCH_DEFAULT_KEXEC_IMAGE_VERIFY_SIG
1617	def_bool y
1618
1619config ARCH_SUPPORTS_KEXEC_HANDOVER
1620	def_bool y
1621
1622config ARCH_SUPPORTS_CRASH_DUMP
1623	def_bool y
1624
1625config ARCH_DEFAULT_CRASH_DUMP
1626	def_bool y
1627
1628config ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION
1629	def_bool CRASH_RESERVE
1630
1631config TRANS_TABLE
1632	def_bool y
1633	depends on HIBERNATION || KEXEC_CORE
1634
1635config XEN_DOM0
1636	def_bool y
1637	depends on XEN
1638
1639config XEN
1640	bool "Xen guest support on ARM64"
1641	depends on ARM64 && OF
1642	select SWIOTLB_XEN
1643	select PARAVIRT
1644	help
1645	  Say Y if you want to run Linux in a Virtual Machine on Xen on ARM64.
1646
1647# include/linux/mmzone.h requires the following to be true:
1648#
1649#   MAX_PAGE_ORDER + PAGE_SHIFT <= SECTION_SIZE_BITS
1650#
1651# so the maximum value of MAX_PAGE_ORDER is SECTION_SIZE_BITS - PAGE_SHIFT:
1652#
1653#     | SECTION_SIZE_BITS |  PAGE_SHIFT  |  max MAX_PAGE_ORDER  |  default MAX_PAGE_ORDER |
1654# ----+-------------------+--------------+----------------------+-------------------------+
1655# 4K  |       27          |      12      |       15             |         10              |
1656# 16K |       27          |      14      |       13             |         11              |
1657# 64K |       29          |      16      |       13             |         13              |
1658config ARCH_FORCE_MAX_ORDER
1659	int
1660	default "13" if ARM64_64K_PAGES
1661	default "11" if ARM64_16K_PAGES
1662	default "10"
1663	help
1664	  The kernel page allocator limits the size of maximal physically
1665	  contiguous allocations. The limit is called MAX_PAGE_ORDER and it
1666	  defines the maximal power of two of number of pages that can be
1667	  allocated as a single contiguous block. This option allows
1668	  overriding the default setting when ability to allocate very
1669	  large blocks of physically contiguous memory is required.
1670
1671	  The maximal size of allocation cannot exceed the size of the
1672	  section, so the value of MAX_PAGE_ORDER should satisfy
1673
1674	    MAX_PAGE_ORDER + PAGE_SHIFT <= SECTION_SIZE_BITS
1675
1676	  Don't change if unsure.
1677
1678config UNMAP_KERNEL_AT_EL0
1679	bool "Unmap kernel when running in userspace (KPTI)" if EXPERT
1680	default y
1681	help
1682	  Speculation attacks against some high-performance processors can
1683	  be used to bypass MMU permission checks and leak kernel data to
1684	  userspace. This can be defended against by unmapping the kernel
1685	  when running in userspace, mapping it back in on exception entry
1686	  via a trampoline page in the vector table.
1687
1688	  If unsure, say Y.
1689
1690config MITIGATE_SPECTRE_BRANCH_HISTORY
1691	bool "Mitigate Spectre style attacks against branch history" if EXPERT
1692	default y
1693	help
1694	  Speculation attacks against some high-performance processors can
1695	  make use of branch history to influence future speculation.
1696	  When taking an exception from user-space, a sequence of branches
1697	  or a firmware call overwrites the branch history.
1698
1699config ARM64_SW_TTBR0_PAN
1700	bool "Emulate Privileged Access Never using TTBR0_EL1 switching"
1701	depends on !KCSAN
1702	help
1703	  Enabling this option prevents the kernel from accessing
1704	  user-space memory directly by pointing TTBR0_EL1 to a reserved
1705	  zeroed area and reserved ASID. The user access routines
1706	  restore the valid TTBR0_EL1 temporarily.
1707
1708config ARM64_TAGGED_ADDR_ABI
1709	bool "Enable the tagged user addresses syscall ABI"
1710	default y
1711	help
1712	  When this option is enabled, user applications can opt in to a
1713	  relaxed ABI via prctl() allowing tagged addresses to be passed
1714	  to system calls as pointer arguments. For details, see
1715	  Documentation/arch/arm64/tagged-address-abi.rst.
1716
1717menuconfig COMPAT
1718	bool "Kernel support for 32-bit EL0"
1719	depends on ARM64_4K_PAGES || EXPERT
1720	select HAVE_UID16
1721	select OLD_SIGSUSPEND3
1722	select COMPAT_OLD_SIGACTION
1723	help
1724	  This option enables support for a 32-bit EL0 running under a 64-bit
1725	  kernel at EL1. AArch32-specific components such as system calls,
1726	  the user helper functions, VFP support and the ptrace interface are
1727	  handled appropriately by the kernel.
1728
1729	  If you use a page size other than 4KB (i.e, 16KB or 64KB), please be aware
1730	  that you will only be able to execute AArch32 binaries that were compiled
1731	  with page size aligned segments.
1732
1733	  If you want to execute 32-bit userspace applications, say Y.
1734
1735if COMPAT
1736
1737config KUSER_HELPERS
1738	bool "Enable kuser helpers page for 32-bit applications"
1739	default y
1740	help
1741	  Warning: disabling this option may break 32-bit user programs.
1742
1743	  Provide kuser helpers to compat tasks. The kernel provides
1744	  helper code to userspace in read only form at a fixed location
1745	  to allow userspace to be independent of the CPU type fitted to
1746	  the system. This permits binaries to be run on ARMv4 through
1747	  to ARMv8 without modification.
1748
1749	  See Documentation/arch/arm/kernel_user_helpers.rst for details.
1750
1751	  However, the fixed address nature of these helpers can be used
1752	  by ROP (return orientated programming) authors when creating
1753	  exploits.
1754
1755	  If all of the binaries and libraries which run on your platform
1756	  are built specifically for your platform, and make no use of
1757	  these helpers, then you can turn this option off to hinder
1758	  such exploits. However, in that case, if a binary or library
1759	  relying on those helpers is run, it will not function correctly.
1760
1761	  Say N here only if you are absolutely certain that you do not
1762	  need these helpers; otherwise, the safe option is to say Y.
1763
1764config COMPAT_VDSO
1765	bool "Enable vDSO for 32-bit applications"
1766	depends on !CPU_BIG_ENDIAN
1767	depends on (CC_IS_CLANG && LD_IS_LLD) || "$(CROSS_COMPILE_COMPAT)" != ""
1768	default y
1769	help
1770	  Place in the process address space of 32-bit applications an
1771	  ELF shared object providing fast implementations of gettimeofday
1772	  and clock_gettime.
1773
1774	  You must have a 32-bit build of glibc 2.22 or later for programs
1775	  to seamlessly take advantage of this.
1776
1777config THUMB2_COMPAT_VDSO
1778	bool "Compile the 32-bit vDSO for Thumb-2 mode" if EXPERT
1779	depends on COMPAT_VDSO
1780	default y
1781	help
1782	  Compile the compat vDSO with '-mthumb -fomit-frame-pointer' if y,
1783	  otherwise with '-marm'.
1784
1785config COMPAT_ALIGNMENT_FIXUPS
1786	bool "Fix up misaligned multi-word loads and stores in user space"
1787
1788menuconfig ARMV8_DEPRECATED
1789	bool "Emulate deprecated/obsolete ARMv8 instructions"
1790	depends on SYSCTL
1791	help
1792	  Legacy software support may require certain instructions
1793	  that have been deprecated or obsoleted in the architecture.
1794
1795	  Enable this config to enable selective emulation of these
1796	  features.
1797
1798	  If unsure, say Y
1799
1800if ARMV8_DEPRECATED
1801
1802config SWP_EMULATION
1803	bool "Emulate SWP/SWPB instructions"
1804	help
1805	  ARMv8 obsoletes the use of A32 SWP/SWPB instructions such that
1806	  they are always undefined. Say Y here to enable software
1807	  emulation of these instructions for userspace using LDXR/STXR.
1808	  This feature can be controlled at runtime with the abi.swp
1809	  sysctl which is disabled by default.
1810
1811	  In some older versions of glibc [<=2.8] SWP is used during futex
1812	  trylock() operations with the assumption that the code will not
1813	  be preempted. This invalid assumption may be more likely to fail
1814	  with SWP emulation enabled, leading to deadlock of the user
1815	  application.
1816
1817	  NOTE: when accessing uncached shared regions, LDXR/STXR rely
1818	  on an external transaction monitoring block called a global
1819	  monitor to maintain update atomicity. If your system does not
1820	  implement a global monitor, this option can cause programs that
1821	  perform SWP operations to uncached memory to deadlock.
1822
1823	  If unsure, say Y
1824
1825config CP15_BARRIER_EMULATION
1826	bool "Emulate CP15 Barrier instructions"
1827	help
1828	  The CP15 barrier instructions - CP15ISB, CP15DSB, and
1829	  CP15DMB - are deprecated in ARMv8 (and ARMv7). It is
1830	  strongly recommended to use the ISB, DSB, and DMB
1831	  instructions instead.
1832
1833	  Say Y here to enable software emulation of these
1834	  instructions for AArch32 userspace code. When this option is
1835	  enabled, CP15 barrier usage is traced which can help
1836	  identify software that needs updating. This feature can be
1837	  controlled at runtime with the abi.cp15_barrier sysctl.
1838
1839	  If unsure, say Y
1840
1841config SETEND_EMULATION
1842	bool "Emulate SETEND instruction"
1843	help
1844	  The SETEND instruction alters the data-endianness of the
1845	  AArch32 EL0, and is deprecated in ARMv8.
1846
1847	  Say Y here to enable software emulation of the instruction
1848	  for AArch32 userspace code. This feature can be controlled
1849	  at runtime with the abi.setend sysctl.
1850
1851	  Note: All the cpus on the system must have mixed endian support at EL0
1852	  for this feature to be enabled. If a new CPU - which doesn't support mixed
1853	  endian - is hotplugged in after this feature has been enabled, there could
1854	  be unexpected results in the applications.
1855
1856	  If unsure, say Y
1857endif # ARMV8_DEPRECATED
1858
1859endif # COMPAT
1860
1861menu "ARMv8.1 architectural features"
1862
1863config ARM64_HW_AFDBM
1864	bool "Support for hardware updates of the Access and Dirty page flags"
1865	default y
1866	help
1867	  The ARMv8.1 architecture extensions introduce support for
1868	  hardware updates of the access and dirty information in page
1869	  table entries. When enabled in TCR_EL1 (HA and HD bits) on
1870	  capable processors, accesses to pages with PTE_AF cleared will
1871	  set this bit instead of raising an access flag fault.
1872	  Similarly, writes to read-only pages with the DBM bit set will
1873	  clear the read-only bit (AP[2]) instead of raising a
1874	  permission fault.
1875
1876	  Kernels built with this configuration option enabled continue
1877	  to work on pre-ARMv8.1 hardware and the performance impact is
1878	  minimal. If unsure, say Y.
1879
1880endmenu # "ARMv8.1 architectural features"
1881
1882menu "ARMv8.2 architectural features"
1883
1884config ARM64_PMEM
1885	bool "Enable support for persistent memory"
1886	select ARCH_HAS_PMEM_API
1887	select ARCH_HAS_UACCESS_FLUSHCACHE
1888	help
1889	  Say Y to enable support for the persistent memory API based on the
1890	  ARMv8.2 DCPoP feature.
1891
1892	  The feature is detected at runtime, and the kernel will use DC CVAC
1893	  operations if DC CVAP is not supported (following the behaviour of
1894	  DC CVAP itself if the system does not define a point of persistence).
1895
1896config ARM64_RAS_EXTN
1897	bool "Enable support for RAS CPU Extensions"
1898	default y
1899	help
1900	  CPUs that support the Reliability, Availability and Serviceability
1901	  (RAS) Extensions, part of ARMv8.2 are able to track faults and
1902	  errors, classify them and report them to software.
1903
1904	  On CPUs with these extensions system software can use additional
1905	  barriers to determine if faults are pending and read the
1906	  classification from a new set of registers.
1907
1908	  Selecting this feature will allow the kernel to use these barriers
1909	  and access the new registers if the system supports the extension.
1910	  Platform RAS features may additionally depend on firmware support.
1911
1912config ARM64_CNP
1913	bool "Enable support for Common Not Private (CNP) translations"
1914	default y
1915	help
1916	  Common Not Private (CNP) allows translation table entries to
1917	  be shared between different PEs in the same inner shareable
1918	  domain, so the hardware can use this fact to optimise the
1919	  caching of such entries in the TLB.
1920
1921	  Selecting this option allows the CNP feature to be detected
1922	  at runtime, and does not affect PEs that do not implement
1923	  this feature.
1924
1925endmenu # "ARMv8.2 architectural features"
1926
1927menu "ARMv8.3 architectural features"
1928
1929config ARM64_PTR_AUTH
1930	bool "Enable support for pointer authentication"
1931	default y
1932	help
1933	  Pointer authentication (part of the ARMv8.3 Extensions) provides
1934	  instructions for signing and authenticating pointers against secret
1935	  keys, which can be used to mitigate Return Oriented Programming (ROP)
1936	  and other attacks.
1937
1938	  This option enables these instructions at EL0 (i.e. for userspace).
1939	  Choosing this option will cause the kernel to initialise secret keys
1940	  for each process at exec() time, with these keys being
1941	  context-switched along with the process.
1942
1943	  The feature is detected at runtime. If the feature is not present in
1944	  hardware it will not be advertised to userspace/KVM guest nor will it
1945	  be enabled.
1946
1947	  If the feature is present on the boot CPU but not on a late CPU, then
1948	  the late CPU will be parked. Also, if the boot CPU does not have
1949	  address auth and the late CPU has then the late CPU will still boot
1950	  but with the feature disabled. On such a system, this option should
1951	  not be selected.
1952
1953config ARM64_PTR_AUTH_KERNEL
1954	bool "Use pointer authentication for kernel"
1955	default y
1956	depends on ARM64_PTR_AUTH
1957	# Modern compilers insert a .note.gnu.property section note for PAC
1958	# which is only understood by binutils starting with version 2.33.1.
1959	depends on LD_IS_LLD || LD_VERSION >= 23301 || (CC_IS_GCC && GCC_VERSION < 90100)
1960	depends on !CC_IS_CLANG || AS_HAS_CFI_NEGATE_RA_STATE
1961	depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_ARGS)
1962	help
1963	  If the compiler supports the -mbranch-protection or
1964	  -msign-return-address flag (e.g. GCC 7 or later), then this option
1965	  will cause the kernel itself to be compiled with return address
1966	  protection. In this case, and if the target hardware is known to
1967	  support pointer authentication, then CONFIG_STACKPROTECTOR can be
1968	  disabled with minimal loss of protection.
1969
1970	  This feature works with FUNCTION_GRAPH_TRACER option only if
1971	  DYNAMIC_FTRACE_WITH_ARGS is enabled.
1972
1973config CC_HAS_BRANCH_PROT_PAC_RET
1974	# GCC 9 or later, clang 8 or later
1975	def_bool $(cc-option,-mbranch-protection=pac-ret+leaf)
1976
1977config AS_HAS_CFI_NEGATE_RA_STATE
1978	# binutils 2.34+
1979	def_bool $(as-instr,.cfi_startproc\n.cfi_negate_ra_state\n.cfi_endproc\n)
1980
1981endmenu # "ARMv8.3 architectural features"
1982
1983menu "ARMv8.4 architectural features"
1984
1985config ARM64_AMU_EXTN
1986	bool "Enable support for the Activity Monitors Unit CPU extension"
1987	default y
1988	help
1989	  The activity monitors extension is an optional extension introduced
1990	  by the ARMv8.4 CPU architecture. This enables support for version 1
1991	  of the activity monitors architecture, AMUv1.
1992
1993	  To enable the use of this extension on CPUs that implement it, say Y.
1994
1995	  Note that for architectural reasons, firmware _must_ implement AMU
1996	  support when running on CPUs that present the activity monitors
1997	  extension. The required support is present in:
1998	    * Version 1.5 and later of the ARM Trusted Firmware
1999
2000	  For kernels that have this configuration enabled but boot with broken
2001	  firmware, you may need to say N here until the firmware is fixed.
2002	  Otherwise you may experience firmware panics or lockups when
2003	  accessing the counter registers. Even if you are not observing these
2004	  symptoms, the values returned by the register reads might not
2005	  correctly reflect reality. Most commonly, the value read will be 0,
2006	  indicating that the counter is not enabled.
2007
2008config ARM64_TLB_RANGE
2009	bool "Enable support for tlbi range feature"
2010	default y
2011	help
2012	  ARMv8.4-TLBI provides TLBI invalidation instruction that apply to a
2013	  range of input addresses.
2014
2015config ARM64_MPAM
2016	bool "Enable support for MPAM"
2017	select ARM64_MPAM_DRIVER if EXPERT	# does nothing yet
2018	select ACPI_MPAM if ACPI
2019	help
2020	  Memory System Resource Partitioning and Monitoring (MPAM) is an
2021	  optional extension to the Arm architecture that allows each
2022	  transaction issued to the memory system to be labelled with a
2023	  Partition identifier (PARTID) and Performance Monitoring Group
2024	  identifier (PMG).
2025
2026	  Memory system components, such as the caches, can be configured with
2027	  policies to control how much of various physical resources (such as
2028	  memory bandwidth or cache memory) the transactions labelled with each
2029	  PARTID can consume.  Depending on the capabilities of the hardware,
2030	  the PARTID and PMG can also be used as filtering criteria to measure
2031	  the memory system resource consumption of different parts of a
2032	  workload.
2033
2034	  Use of this extension requires CPU support, support in the
2035	  Memory System Components (MSC), and a description from firmware
2036	  of where the MSCs are in the address space.
2037
2038	  MPAM is exposed to user-space via the resctrl pseudo filesystem.
2039
2040endmenu # "ARMv8.4 architectural features"
2041
2042menu "ARMv8.5 architectural features"
2043
2044config AS_HAS_ARMV8_5
2045	def_bool $(cc-option,-Wa$(comma)-march=armv8.5-a)
2046
2047config ARM64_BTI
2048	bool "Branch Target Identification support"
2049	default y
2050	help
2051	  Branch Target Identification (part of the ARMv8.5 Extensions)
2052	  provides a mechanism to limit the set of locations to which computed
2053	  branch instructions such as BR or BLR can jump.
2054
2055	  To make use of BTI on CPUs that support it, say Y.
2056
2057	  BTI is intended to provide complementary protection to other control
2058	  flow integrity protection mechanisms, such as the Pointer
2059	  authentication mechanism provided as part of the ARMv8.3 Extensions.
2060	  For this reason, it does not make sense to enable this option without
2061	  also enabling support for pointer authentication.  Thus, when
2062	  enabling this option you should also select ARM64_PTR_AUTH=y.
2063
2064	  Userspace binaries must also be specifically compiled to make use of
2065	  this mechanism.  If you say N here or the hardware does not support
2066	  BTI, such binaries can still run, but you get no additional
2067	  enforcement of branch destinations.
2068
2069config ARM64_BTI_KERNEL
2070	bool "Use Branch Target Identification for kernel"
2071	default y
2072	depends on ARM64_BTI
2073	depends on ARM64_PTR_AUTH_KERNEL
2074	depends on CC_HAS_BRANCH_PROT_PAC_RET_BTI
2075	# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94697
2076	depends on !CC_IS_GCC || GCC_VERSION >= 100100
2077	# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106671
2078	depends on !CC_IS_GCC
2079	depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_ARGS)
2080	help
2081	  Build the kernel with Branch Target Identification annotations
2082	  and enable enforcement of this for kernel code. When this option
2083	  is enabled and the system supports BTI all kernel code including
2084	  modular code must have BTI enabled.
2085
2086config CC_HAS_BRANCH_PROT_PAC_RET_BTI
2087	# GCC 9 or later, clang 8 or later
2088	def_bool $(cc-option,-mbranch-protection=pac-ret+leaf+bti)
2089
2090config ARM64_E0PD
2091	bool "Enable support for E0PD"
2092	default y
2093	help
2094	  E0PD (part of the ARMv8.5 extensions) allows us to ensure
2095	  that EL0 accesses made via TTBR1 always fault in constant time,
2096	  providing similar benefits to KASLR as those provided by KPTI, but
2097	  with lower overhead and without disrupting legitimate access to
2098	  kernel memory such as SPE.
2099
2100	  This option enables E0PD for TTBR1 where available.
2101
2102config ARM64_AS_HAS_MTE
2103	# Initial support for MTE went in binutils 2.32.0, checked with
2104	# ".arch armv8.5-a+memtag" below. However, this was incomplete
2105	# as a late addition to the final architecture spec (LDGM/STGM)
2106	# is only supported in the newer 2.32.x and 2.33 binutils
2107	# versions, hence the extra "stgm" instruction check below.
2108	def_bool $(as-instr,.arch armv8.5-a+memtag\nstgm xzr$(comma)[x0])
2109
2110config ARM64_MTE
2111	bool "Memory Tagging Extension support"
2112	default y
2113	depends on ARM64_AS_HAS_MTE && ARM64_TAGGED_ADDR_ABI
2114	depends on AS_HAS_ARMV8_5
2115	# Required for tag checking in the uaccess routines
2116	select ARCH_HAS_SUBPAGE_FAULTS
2117	select ARCH_USES_HIGH_VMA_FLAGS
2118	select ARCH_USES_PG_ARCH_2
2119	select ARCH_USES_PG_ARCH_3
2120	help
2121	  Memory Tagging (part of the ARMv8.5 Extensions) provides
2122	  architectural support for run-time, always-on detection of
2123	  various classes of memory error to aid with software debugging
2124	  to eliminate vulnerabilities arising from memory-unsafe
2125	  languages.
2126
2127	  This option enables the support for the Memory Tagging
2128	  Extension at EL0 (i.e. for userspace).
2129
2130	  Selecting this option allows the feature to be detected at
2131	  runtime. Any secondary CPU not implementing this feature will
2132	  not be allowed a late bring-up.
2133
2134	  Userspace binaries that want to use this feature must
2135	  explicitly opt in. The mechanism for the userspace is
2136	  described in:
2137
2138	  Documentation/arch/arm64/memory-tagging-extension.rst.
2139
2140endmenu # "ARMv8.5 architectural features"
2141
2142menu "ARMv8.7 architectural features"
2143
2144config ARM64_EPAN
2145	bool "Enable support for Enhanced Privileged Access Never (EPAN)"
2146	default y
2147	help
2148	  Enhanced Privileged Access Never (EPAN) allows Privileged
2149	  Access Never to be used with Execute-only mappings.
2150
2151	  The feature is detected at runtime, and will remain disabled
2152	  if the cpu does not implement the feature.
2153endmenu # "ARMv8.7 architectural features"
2154
2155config AS_HAS_MOPS
2156	def_bool $(as-instr,.arch_extension mops)
2157
2158menu "ARMv8.9 architectural features"
2159
2160config ARM64_POE
2161	prompt "Permission Overlay Extension"
2162	def_bool y
2163	select ARCH_USES_HIGH_VMA_FLAGS
2164	select ARCH_HAS_PKEYS
2165	help
2166	  The Permission Overlay Extension is used to implement Memory
2167	  Protection Keys. Memory Protection Keys provides a mechanism for
2168	  enforcing page-based protections, but without requiring modification
2169	  of the page tables when an application changes protection domains.
2170
2171	  For details, see Documentation/core-api/protection-keys.rst
2172
2173	  If unsure, say y.
2174
2175config ARCH_PKEY_BITS
2176	int
2177	default 3
2178
2179config ARM64_HAFT
2180	bool "Support for Hardware managed Access Flag for Table Descriptors"
2181	depends on ARM64_HW_AFDBM
2182	default y
2183	help
2184	  The ARMv8.9/ARMv9.5 introduces the feature Hardware managed Access
2185	  Flag for Table descriptors. When enabled an architectural executed
2186	  memory access will update the Access Flag in each Table descriptor
2187	  which is accessed during the translation table walk and for which
2188	  the Access Flag is 0. The Access Flag of the Table descriptor use
2189	  the same bit of PTE_AF.
2190
2191	  The feature will only be enabled if all the CPUs in the system
2192	  support this feature. If unsure, say Y.
2193
2194endmenu # "ARMv8.9 architectural features"
2195
2196menu "ARMv9.4 architectural features"
2197
2198config ARM64_GCS
2199	bool "Enable support for Guarded Control Stack (GCS)"
2200	default y
2201	select ARCH_HAS_USER_SHADOW_STACK
2202	select ARCH_USES_HIGH_VMA_FLAGS
2203	help
2204	  Guarded Control Stack (GCS) provides support for a separate
2205	  stack with restricted access which contains only return
2206	  addresses.  This can be used to harden against some attacks
2207	  by comparing return address used by the program with what is
2208	  stored in the GCS, and may also be used to efficiently obtain
2209	  the call stack for applications such as profiling.
2210
2211	  The feature is detected at runtime, and will remain disabled
2212	  if the system does not implement the feature.
2213
2214endmenu # "ARMv9.4 architectural features"
2215
2216config ARM64_SVE
2217	bool "ARM Scalable Vector Extension support"
2218	default y
2219	help
2220	  The Scalable Vector Extension (SVE) is an extension to the AArch64
2221	  execution state which complements and extends the SIMD functionality
2222	  of the base architecture to support much larger vectors and to enable
2223	  additional vectorisation opportunities.
2224
2225	  To enable use of this extension on CPUs that implement it, say Y.
2226
2227	  On CPUs that support the SVE2 extensions, this option will enable
2228	  those too.
2229
2230	  Note that for architectural reasons, firmware _must_ implement SVE
2231	  support when running on SVE capable hardware.  The required support
2232	  is present in:
2233
2234	    * version 1.5 and later of the ARM Trusted Firmware
2235	    * the AArch64 boot wrapper since commit 5e1261e08abf
2236	      ("bootwrapper: SVE: Enable SVE for EL2 and below").
2237
2238	  For other firmware implementations, consult the firmware documentation
2239	  or vendor.
2240
2241	  If you need the kernel to boot on SVE-capable hardware with broken
2242	  firmware, you may need to say N here until you get your firmware
2243	  fixed.  Otherwise, you may experience firmware panics or lockups when
2244	  booting the kernel.  If unsure and you are not observing these
2245	  symptoms, you should assume that it is safe to say Y.
2246
2247config ARM64_SME
2248	bool "ARM Scalable Matrix Extension support"
2249	default y
2250	depends on ARM64_SVE
2251	help
2252	  The Scalable Matrix Extension (SME) is an extension to the AArch64
2253	  execution state which utilises a substantial subset of the SVE
2254	  instruction set, together with the addition of new architectural
2255	  register state capable of holding two dimensional matrix tiles to
2256	  enable various matrix operations.
2257
2258config ARM64_PSEUDO_NMI
2259	bool "Support for NMI-like interrupts"
2260	select ARM_GIC_V3
2261	help
2262	  Adds support for mimicking Non-Maskable Interrupts through the use of
2263	  GIC interrupt priority. This support requires version 3 or later of
2264	  ARM GIC.
2265
2266	  This high priority configuration for interrupts needs to be
2267	  explicitly enabled by setting the kernel parameter
2268	  "irqchip.gicv3_pseudo_nmi" to 1.
2269
2270	  If unsure, say N
2271
2272if ARM64_PSEUDO_NMI
2273config ARM64_DEBUG_PRIORITY_MASKING
2274	bool "Debug interrupt priority masking"
2275	help
2276	  This adds runtime checks to functions enabling/disabling
2277	  interrupts when using priority masking. The additional checks verify
2278	  the validity of ICC_PMR_EL1 when calling concerned functions.
2279
2280	  If unsure, say N
2281endif # ARM64_PSEUDO_NMI
2282
2283config RELOCATABLE
2284	bool "Build a relocatable kernel image" if EXPERT
2285	select ARCH_HAS_RELR
2286	default y
2287	help
2288	  This builds the kernel as a Position Independent Executable (PIE),
2289	  which retains all relocation metadata required to relocate the
2290	  kernel binary at runtime to a different virtual address than the
2291	  address it was linked at.
2292	  Since AArch64 uses the RELA relocation format, this requires a
2293	  relocation pass at runtime even if the kernel is loaded at the
2294	  same address it was linked at.
2295
2296config RANDOMIZE_BASE
2297	bool "Randomize the address of the kernel image"
2298	select RELOCATABLE
2299	help
2300	  Randomizes the virtual address at which the kernel image is
2301	  loaded, as a security feature that deters exploit attempts
2302	  relying on knowledge of the location of kernel internals.
2303
2304	  It is the bootloader's job to provide entropy, by passing a
2305	  random u64 value in /chosen/kaslr-seed at kernel entry.
2306
2307	  When booting via the UEFI stub, it will invoke the firmware's
2308	  EFI_RNG_PROTOCOL implementation (if available) to supply entropy
2309	  to the kernel proper. In addition, it will randomise the physical
2310	  location of the kernel Image as well.
2311
2312	  If unsure, say N.
2313
2314config RANDOMIZE_MODULE_REGION_FULL
2315	bool "Randomize the module region over a 2 GB range"
2316	depends on RANDOMIZE_BASE
2317	default y
2318	help
2319	  Randomizes the location of the module region inside a 2 GB window
2320	  covering the core kernel. This way, it is less likely for modules
2321	  to leak information about the location of core kernel data structures
2322	  but it does imply that function calls between modules and the core
2323	  kernel will need to be resolved via veneers in the module PLT.
2324
2325	  When this option is not set, the module region will be randomized over
2326	  a limited range that contains the [_stext, _etext] interval of the
2327	  core kernel, so branch relocations are almost always in range unless
2328	  the region is exhausted. In this particular case of region
2329	  exhaustion, modules might be able to fall back to a larger 2GB area.
2330
2331config CC_HAVE_STACKPROTECTOR_SYSREG
2332	def_bool $(cc-option,-mstack-protector-guard=sysreg -mstack-protector-guard-reg=sp_el0 -mstack-protector-guard-offset=0)
2333
2334config STACKPROTECTOR_PER_TASK
2335	def_bool y
2336	depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_SYSREG
2337
2338config UNWIND_PATCH_PAC_INTO_SCS
2339	bool "Enable shadow call stack dynamically using code patching"
2340	depends on CC_IS_CLANG
2341	depends on ARM64_PTR_AUTH_KERNEL && CC_HAS_BRANCH_PROT_PAC_RET
2342	depends on SHADOW_CALL_STACK
2343	select UNWIND_TABLES
2344	select DYNAMIC_SCS
2345
2346config ARM64_CONTPTE
2347	bool "Contiguous PTE mappings for user memory" if EXPERT
2348	depends on TRANSPARENT_HUGEPAGE
2349	default y
2350	help
2351	  When enabled, user mappings are configured using the PTE contiguous
2352	  bit, for any mappings that meet the size and alignment requirements.
2353	  This reduces TLB pressure and improves performance.
2354
2355endmenu # "Kernel Features"
2356
2357menu "Boot options"
2358
2359config ARM64_ACPI_PARKING_PROTOCOL
2360	bool "Enable support for the ARM64 ACPI parking protocol"
2361	depends on ACPI
2362	help
2363	  Enable support for the ARM64 ACPI parking protocol. If disabled
2364	  the kernel will not allow booting through the ARM64 ACPI parking
2365	  protocol even if the corresponding data is present in the ACPI
2366	  MADT table.
2367
2368config CMDLINE
2369	string "Default kernel command string"
2370	default ""
2371	help
2372	  Provide a set of default command-line options at build time by
2373	  entering them here. As a minimum, you should specify the the
2374	  root device (e.g. root=/dev/nfs).
2375
2376choice
2377	prompt "Kernel command line type"
2378	depends on CMDLINE != ""
2379	default CMDLINE_FROM_BOOTLOADER
2380	help
2381	  Choose how the kernel will handle the provided default kernel
2382	  command line string.
2383
2384config CMDLINE_FROM_BOOTLOADER
2385	bool "Use bootloader kernel arguments if available"
2386	help
2387	  Uses the command-line options passed by the boot loader. If
2388	  the boot loader doesn't provide any, the default kernel command
2389	  string provided in CMDLINE will be used.
2390
2391config CMDLINE_FORCE
2392	bool "Always use the default kernel command string"
2393	help
2394	  Always use the default kernel command string, even if the boot
2395	  loader passes other arguments to the kernel.
2396	  This is useful if you cannot or don't want to change the
2397	  command-line options your boot loader passes to the kernel.
2398
2399endchoice
2400
2401config EFI_STUB
2402	bool
2403
2404config EFI
2405	bool "UEFI runtime support"
2406	depends on OF && !CPU_BIG_ENDIAN
2407	depends on KERNEL_MODE_NEON
2408	select ARCH_SUPPORTS_ACPI
2409	select LIBFDT
2410	select UCS2_STRING
2411	select EFI_PARAMS_FROM_FDT
2412	select EFI_RUNTIME_WRAPPERS
2413	select EFI_STUB
2414	select EFI_GENERIC_STUB
2415	imply IMA_SECURE_AND_OR_TRUSTED_BOOT
2416	default y
2417	help
2418	  This option provides support for runtime services provided
2419	  by UEFI firmware (such as non-volatile variables, realtime
2420	  clock, and platform reset). A UEFI stub is also provided to
2421	  allow the kernel to be booted as an EFI application. This
2422	  is only useful on systems that have UEFI firmware.
2423
2424config COMPRESSED_INSTALL
2425	bool "Install compressed image by default"
2426	help
2427	  This makes the regular "make install" install the compressed
2428	  image we built, not the legacy uncompressed one.
2429
2430	  You can check that a compressed image works for you by doing
2431	  "make zinstall" first, and verifying that everything is fine
2432	  in your environment before making "make install" do this for
2433	  you.
2434
2435config DMI
2436	bool "Enable support for SMBIOS (DMI) tables"
2437	depends on EFI
2438	default y
2439	help
2440	  This enables SMBIOS/DMI feature for systems.
2441
2442	  This option is only useful on systems that have UEFI firmware.
2443	  However, even with this option, the resultant kernel should
2444	  continue to boot on existing non-UEFI platforms.
2445
2446endmenu # "Boot options"
2447
2448menu "Power management options"
2449
2450source "kernel/power/Kconfig"
2451
2452config ARCH_HIBERNATION_POSSIBLE
2453	def_bool y
2454	depends on CPU_PM
2455
2456config ARCH_HIBERNATION_HEADER
2457	def_bool y
2458	depends on HIBERNATION
2459
2460config ARCH_SUSPEND_POSSIBLE
2461	def_bool y
2462
2463endmenu # "Power management options"
2464
2465menu "CPU Power Management"
2466
2467source "drivers/cpuidle/Kconfig"
2468
2469source "drivers/cpufreq/Kconfig"
2470
2471endmenu # "CPU Power Management"
2472
2473source "drivers/acpi/Kconfig"
2474
2475source "arch/arm64/kvm/Kconfig"
2476
2477source "kernel/livepatch/Kconfig"
2478