xref: /linux/arch/arm64/Kconfig (revision 441c63ff42c4e666304cdd32d23b5fc6bc1ea3cc)
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_LAZY_MMU_MODE
39	select ARCH_HAS_MEMBARRIER_SYNC_CORE
40	select ARCH_HAS_MEM_ENCRYPT
41	select ARCH_SUPPORTS_MSEAL_SYSTEM_MAPPINGS
42	select ARCH_HAS_NMI_SAFE_THIS_CPU_OPS
43	select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
44	select ARCH_HAS_NONLEAF_PMD_YOUNG if ARM64_HAFT
45	select ARCH_HAS_PREEMPT_LAZY
46	select ARCH_HAS_PTDUMP
47	select ARCH_HAS_PTE_SPECIAL
48	select ARCH_HAS_HW_PTE_YOUNG
49	select ARCH_HAS_SETUP_DMA_OPS
50	select ARCH_HAS_SET_DIRECT_MAP
51	select ARCH_HAS_SET_MEMORY
52	select ARCH_HAS_FORCE_DMA_UNENCRYPTED
53	select ARCH_STACKWALK
54	select ARCH_HAS_STRICT_KERNEL_RWX
55	select ARCH_HAS_STRICT_MODULE_RWX
56	select ARCH_HAS_SYNC_DMA_FOR_DEVICE
57	select ARCH_HAS_SYNC_DMA_FOR_CPU
58	select ARCH_HAS_SYSCALL_WRAPPER
59	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
60	select ARCH_HAS_ZONE_DMA_SET if EXPERT
61	select ARCH_HAVE_ELF_PROT
62	select ARCH_HAVE_NMI_SAFE_CMPXCHG
63	select ARCH_HAVE_TRACE_MMIO_ACCESS
64	select ARCH_INLINE_READ_LOCK if !PREEMPTION
65	select ARCH_INLINE_READ_LOCK_BH if !PREEMPTION
66	select ARCH_INLINE_READ_LOCK_IRQ if !PREEMPTION
67	select ARCH_INLINE_READ_LOCK_IRQSAVE if !PREEMPTION
68	select ARCH_INLINE_READ_UNLOCK if !PREEMPTION
69	select ARCH_INLINE_READ_UNLOCK_BH if !PREEMPTION
70	select ARCH_INLINE_READ_UNLOCK_IRQ if !PREEMPTION
71	select ARCH_INLINE_READ_UNLOCK_IRQRESTORE if !PREEMPTION
72	select ARCH_INLINE_WRITE_LOCK if !PREEMPTION
73	select ARCH_INLINE_WRITE_LOCK_BH if !PREEMPTION
74	select ARCH_INLINE_WRITE_LOCK_IRQ if !PREEMPTION
75	select ARCH_INLINE_WRITE_LOCK_IRQSAVE if !PREEMPTION
76	select ARCH_INLINE_WRITE_UNLOCK if !PREEMPTION
77	select ARCH_INLINE_WRITE_UNLOCK_BH if !PREEMPTION
78	select ARCH_INLINE_WRITE_UNLOCK_IRQ if !PREEMPTION
79	select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE if !PREEMPTION
80	select ARCH_INLINE_SPIN_TRYLOCK if !PREEMPTION
81	select ARCH_INLINE_SPIN_TRYLOCK_BH if !PREEMPTION
82	select ARCH_INLINE_SPIN_LOCK if !PREEMPTION
83	select ARCH_INLINE_SPIN_LOCK_BH if !PREEMPTION
84	select ARCH_INLINE_SPIN_LOCK_IRQ if !PREEMPTION
85	select ARCH_INLINE_SPIN_LOCK_IRQSAVE if !PREEMPTION
86	select ARCH_INLINE_SPIN_UNLOCK if !PREEMPTION
87	select ARCH_INLINE_SPIN_UNLOCK_BH if !PREEMPTION
88	select ARCH_INLINE_SPIN_UNLOCK_IRQ if !PREEMPTION
89	select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE if !PREEMPTION
90	select ARCH_KEEP_MEMBLOCK
91	select ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE
92	select ARCH_USE_CMPXCHG_LOCKREF
93	select ARCH_USE_GNU_PROPERTY
94	select ARCH_USE_MEMTEST
95	select ARCH_USE_QUEUED_RWLOCKS
96	select ARCH_USE_QUEUED_SPINLOCKS
97	select ARCH_USE_SYM_ANNOTATIONS
98	select ARCH_SUPPORTS_DEBUG_PAGEALLOC
99	select ARCH_SUPPORTS_HUGETLBFS
100	select ARCH_SUPPORTS_MEMORY_FAILURE
101	select ARCH_SUPPORTS_SHADOW_CALL_STACK if CC_HAVE_SHADOW_CALL_STACK
102	select ARCH_SUPPORTS_LTO_CLANG if CPU_LITTLE_ENDIAN
103	select ARCH_SUPPORTS_LTO_CLANG_THIN
104	select ARCH_SUPPORTS_CFI
105	select ARCH_SUPPORTS_ATOMIC_RMW
106	select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
107	select ARCH_SUPPORTS_NUMA_BALANCING
108	select ARCH_SUPPORTS_PAGE_TABLE_CHECK
109	select ARCH_SUPPORTS_PER_VMA_LOCK
110	select ARCH_SUPPORTS_HUGE_PFNMAP if TRANSPARENT_HUGEPAGE
111	select ARCH_SUPPORTS_RT
112	select ARCH_SUPPORTS_SCHED_SMT
113	select ARCH_SUPPORTS_SCHED_CLUSTER
114	select ARCH_SUPPORTS_SCHED_MC
115	select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
116	select ARCH_WANT_COMPAT_IPC_PARSE_VERSION if COMPAT
117	select ARCH_WANT_DEFAULT_BPF_JIT
118	select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT
119	select ARCH_WANT_FRAME_POINTERS
120	select ARCH_WANT_HUGE_PMD_SHARE if ARM64_4K_PAGES || (ARM64_16K_PAGES && !ARM64_VA_BITS_36)
121	select ARCH_WANT_LD_ORPHAN_WARN
122	select ARCH_WANTS_EXECMEM_LATE
123	select ARCH_WANTS_NO_INSTR
124	select ARCH_WANTS_THP_SWAP if ARM64_4K_PAGES
125	select ARCH_HAS_UBSAN
126	select ARM_AMBA
127	select ARM_ARCH_TIMER
128	select ARM_GIC
129	select AUDIT_ARCH_COMPAT_GENERIC
130	select ARM_GIC_V2M if PCI
131	select ARM_GIC_V3
132	select ARM_GIC_V3_ITS if PCI
133	select ARM_GIC_V5
134	select ARM_PSCI_FW
135	select BUILDTIME_TABLE_SORT
136	select CLONE_BACKWARDS
137	select COMMON_CLK
138	select CPU_PM if (SUSPEND || CPU_IDLE)
139	select CPUMASK_OFFSTACK if NR_CPUS > 256
140	select DCACHE_WORD_ACCESS
141	select HAVE_EXTRA_IPI_TRACEPOINTS
142	select DYNAMIC_FTRACE if FUNCTION_TRACER
143	select DMA_BOUNCE_UNALIGNED_KMALLOC
144	select DMA_DIRECT_REMAP
145	select EDAC_SUPPORT
146	select FRAME_POINTER
147	select FUNCTION_ALIGNMENT_4B
148	select FUNCTION_ALIGNMENT_8B if DYNAMIC_FTRACE_WITH_CALL_OPS
149	select GENERIC_ALLOCATOR
150	select GENERIC_ARCH_TOPOLOGY
151	select GENERIC_CLOCKEVENTS_BROADCAST
152	select GENERIC_CPU_AUTOPROBE
153	select GENERIC_CPU_CACHE_MAINTENANCE
154	select GENERIC_CPU_DEVICES
155	select GENERIC_CPU_VULNERABILITIES
156	select GENERIC_EARLY_IOREMAP
157	select GENERIC_IDLE_POLL_SETUP
158	select GENERIC_IOREMAP
159	select GENERIC_IRQ_ENTRY
160	select GENERIC_IRQ_IPI
161	select GENERIC_IRQ_KEXEC_CLEAR_VM_FORWARD
162	select GENERIC_IRQ_PROBE
163	select GENERIC_IRQ_SHOW
164	select GENERIC_IRQ_SHOW_LEVEL
165	select GENERIC_LIB_DEVMEM_IS_ALLOWED
166	select GENERIC_PCI_IOMAP
167	select GENERIC_SCHED_CLOCK
168	select GENERIC_SMP_IDLE_THREAD
169	select GENERIC_TIME_VSYSCALL
170	select GENERIC_GETTIMEOFDAY
171	select HARDIRQS_SW_RESEND
172	select HAS_IOPORT
173	select HAVE_MOVE_PMD
174	select HAVE_MOVE_PUD
175	select HAVE_PCI
176	select HAVE_ACPI_APEI if (ACPI && EFI)
177	select HAVE_ALIGNED_STRUCT_PAGE
178	select HAVE_ARCH_AUDITSYSCALL
179	select HAVE_ARCH_BITREVERSE
180	select HAVE_ARCH_COMPILER_H
181	select HAVE_ARCH_HUGE_VMALLOC
182	select HAVE_ARCH_HUGE_VMAP
183	select HAVE_ARCH_JUMP_LABEL
184	select HAVE_ARCH_JUMP_LABEL_RELATIVE
185	select HAVE_ARCH_KASAN
186	select HAVE_ARCH_KASAN_VMALLOC
187	select HAVE_ARCH_KASAN_SW_TAGS
188	select HAVE_ARCH_KASAN_HW_TAGS if ARM64_MTE
189	# Some instrumentation may be unsound, hence EXPERT
190	select HAVE_ARCH_KCSAN if EXPERT
191	select HAVE_ARCH_KFENCE
192	select HAVE_ARCH_KGDB
193	select HAVE_ARCH_KSTACK_ERASE
194	select HAVE_ARCH_MMAP_RND_BITS
195	select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT
196	select HAVE_ARCH_PREL32_RELOCATIONS
197	select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET
198	select HAVE_ARCH_SECCOMP_FILTER
199	select HAVE_ARCH_THREAD_STRUCT_WHITELIST
200	select HAVE_ARCH_TRACEHOOK
201	select HAVE_ARCH_TRANSPARENT_HUGEPAGE
202	select HAVE_ARCH_VMAP_STACK
203	select HAVE_ARM_SMCCC
204	select HAVE_ASM_MODVERSIONS
205	select HAVE_EBPF_JIT
206	select HAVE_C_RECORDMCOUNT
207	select HAVE_CMPXCHG_DOUBLE
208	select HAVE_CMPXCHG_LOCAL
209	select HAVE_CONTEXT_TRACKING_USER
210	select HAVE_DEBUG_KMEMLEAK
211	select HAVE_DMA_CONTIGUOUS
212	select HAVE_DYNAMIC_FTRACE
213	select HAVE_DYNAMIC_FTRACE_WITH_ARGS \
214		if (GCC_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS || \
215		    CLANG_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS)
216	select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS \
217		if DYNAMIC_FTRACE_WITH_ARGS && DYNAMIC_FTRACE_WITH_CALL_OPS
218	select HAVE_DYNAMIC_FTRACE_WITH_CALL_OPS \
219		if (DYNAMIC_FTRACE_WITH_ARGS && !CFI && \
220		    (CC_IS_CLANG || !CC_OPTIMIZE_FOR_SIZE))
221	select FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY \
222		if DYNAMIC_FTRACE_WITH_ARGS
223	select HAVE_SAMPLE_FTRACE_DIRECT
224	select HAVE_SAMPLE_FTRACE_DIRECT_MULTI
225	select HAVE_BUILDTIME_MCOUNT_SORT
226	select HAVE_EFFICIENT_UNALIGNED_ACCESS
227	select HAVE_GUP_FAST
228	select HAVE_FTRACE_GRAPH_FUNC
229	select HAVE_FUNCTION_TRACER
230	select HAVE_FUNCTION_ERROR_INJECTION
231	select HAVE_FUNCTION_GRAPH_FREGS
232	select HAVE_FUNCTION_GRAPH_TRACER
233	select HAVE_GCC_PLUGINS
234	select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && \
235		HW_PERF_EVENTS && HAVE_PERF_EVENTS_NMI
236	select HAVE_HW_BREAKPOINT if PERF_EVENTS
237	select HAVE_IOREMAP_PROT
238	select HAVE_IRQ_TIME_ACCOUNTING
239	select HAVE_LIVEPATCH
240	select HAVE_MOD_ARCH_SPECIFIC
241	select HAVE_NMI
242	select HAVE_PERF_EVENTS
243	select HAVE_PERF_EVENTS_NMI if ARM64_PSEUDO_NMI
244	select HAVE_PERF_REGS
245	select HAVE_PERF_USER_STACK_DUMP
246	select HAVE_PREEMPT_DYNAMIC_KEY
247	select HAVE_REGS_AND_STACK_ACCESS_API
248	select HAVE_RELIABLE_STACKTRACE
249	select HAVE_POSIX_CPU_TIMERS_TASK_WORK
250	select HAVE_FUNCTION_ARG_ACCESS_API
251	select MMU_GATHER_RCU_TABLE_FREE
252	select HAVE_RSEQ
253	select HAVE_RUST if RUSTC_SUPPORTS_ARM64
254	select HAVE_STACKPROTECTOR
255	select HAVE_STATIC_CALL if CFI
256	select HAVE_SYSCALL_TRACEPOINTS
257	select HAVE_KPROBES
258	select HAVE_KRETPROBES
259	select HAVE_GENERIC_VDSO
260	select HOTPLUG_CORE_SYNC_DEAD if HOTPLUG_CPU
261	select HOTPLUG_SMT if HOTPLUG_CPU
262	select IRQ_DOMAIN
263	select IRQ_FORCED_THREADING
264	select JUMP_LABEL
265	select KASAN_VMALLOC if KASAN
266	select LOCK_MM_AND_FIND_VMA
267	select MODULES_USE_ELF_RELA
268	select NEED_DMA_MAP_STATE
269	select NEED_SG_DMA_LENGTH
270	select OF
271	select OF_EARLY_FLATTREE
272	select PCI_DOMAINS_GENERIC if PCI
273	select PCI_ECAM if (ACPI && PCI)
274	select PCI_SYSCALL if PCI
275	select POWER_RESET
276	select POWER_SUPPLY
277	select SPARSE_IRQ
278	select SWIOTLB
279	select SYSCTL_EXCEPTION_TRACE
280	select THREAD_INFO_IN_TASK
281	select HAVE_ARCH_USERFAULTFD_MINOR if USERFAULTFD
282	select HAVE_ARCH_USERFAULTFD_WP if USERFAULTFD
283	select TRACE_IRQFLAGS_SUPPORT
284	select TRACE_IRQFLAGS_NMI_SUPPORT
285	select HAVE_SOFTIRQ_ON_OWN_STACK
286	select USER_STACKTRACE_SUPPORT
287	select VDSO_GETRANDOM
288	select VMAP_STACK
289	help
290	  ARM 64-bit (AArch64) Linux support.
291
292config RUSTC_SUPPORTS_ARM64
293	def_bool y
294	depends on CPU_LITTLE_ENDIAN
295	# Shadow call stack is only supported on certain rustc versions.
296	#
297	# When using the UNWIND_PATCH_PAC_INTO_SCS option, rustc version 1.80+ is
298	# required due to use of the -Zfixed-x18 flag.
299	#
300	# Otherwise, rustc version 1.82+ is required due to use of the
301	# -Zsanitizer=shadow-call-stack flag.
302	depends on !SHADOW_CALL_STACK || RUSTC_VERSION >= 108200 || RUSTC_VERSION >= 108000 && UNWIND_PATCH_PAC_INTO_SCS
303
304config CLANG_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS
305	def_bool CC_IS_CLANG
306	# https://github.com/ClangBuiltLinux/linux/issues/1507
307	depends on AS_IS_GNU || (AS_IS_LLVM && (LD_IS_LLD || LD_VERSION >= 23600))
308
309config GCC_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS
310	def_bool CC_IS_GCC
311	depends on $(cc-option,-fpatchable-function-entry=2)
312
313config 64BIT
314	def_bool y
315
316config MMU
317	def_bool y
318
319config ARM64_CONT_PTE_SHIFT
320	int
321	default 5 if PAGE_SIZE_64KB
322	default 7 if PAGE_SIZE_16KB
323	default 4
324
325config ARM64_CONT_PMD_SHIFT
326	int
327	default 5 if PAGE_SIZE_64KB
328	default 5 if PAGE_SIZE_16KB
329	default 4
330
331config ARCH_MMAP_RND_BITS_MIN
332	default 14 if PAGE_SIZE_64KB
333	default 16 if PAGE_SIZE_16KB
334	default 18
335
336# max bits determined by the following formula:
337#  VA_BITS - PTDESC_TABLE_SHIFT
338config ARCH_MMAP_RND_BITS_MAX
339	default 19 if ARM64_VA_BITS=36
340	default 24 if ARM64_VA_BITS=39
341	default 27 if ARM64_VA_BITS=42
342	default 30 if ARM64_VA_BITS=47
343	default 29 if (ARM64_VA_BITS=48 || ARM64_VA_BITS=52) && ARM64_64K_PAGES
344	default 31 if (ARM64_VA_BITS=48 || ARM64_VA_BITS=52) && ARM64_16K_PAGES
345	default 33 if (ARM64_VA_BITS=48 || ARM64_VA_BITS=52)
346	default 14 if ARM64_64K_PAGES
347	default 16 if ARM64_16K_PAGES
348	default 18
349
350config ARCH_MMAP_RND_COMPAT_BITS_MIN
351	default 7 if ARM64_64K_PAGES
352	default 9 if ARM64_16K_PAGES
353	default 11
354
355config ARCH_MMAP_RND_COMPAT_BITS_MAX
356	default 16
357
358config NO_IOPORT_MAP
359	def_bool y if !PCI
360
361config STACKTRACE_SUPPORT
362	def_bool y
363
364config ILLEGAL_POINTER_VALUE
365	hex
366	default 0xdead000000000000
367
368config LOCKDEP_SUPPORT
369	def_bool y
370
371config GENERIC_BUG
372	def_bool y
373	depends on BUG
374
375config GENERIC_BUG_RELATIVE_POINTERS
376	def_bool y
377	depends on GENERIC_BUG
378
379config GENERIC_HWEIGHT
380	def_bool y
381
382config GENERIC_CSUM
383	def_bool y
384
385config GENERIC_CALIBRATE_DELAY
386	def_bool y
387
388config SMP
389	def_bool y
390
391config KERNEL_MODE_NEON
392	def_bool y
393
394config FIX_EARLYCON_MEM
395	def_bool y
396
397config PGTABLE_LEVELS
398	int
399	default 2 if ARM64_16K_PAGES && ARM64_VA_BITS_36
400	default 2 if ARM64_64K_PAGES && ARM64_VA_BITS_42
401	default 3 if ARM64_64K_PAGES && (ARM64_VA_BITS_48 || ARM64_VA_BITS_52)
402	default 3 if ARM64_4K_PAGES && ARM64_VA_BITS_39
403	default 3 if ARM64_16K_PAGES && ARM64_VA_BITS_47
404	default 4 if ARM64_16K_PAGES && (ARM64_VA_BITS_48 || ARM64_VA_BITS_52)
405	default 4 if !ARM64_64K_PAGES && ARM64_VA_BITS_48
406	default 5 if ARM64_4K_PAGES && ARM64_VA_BITS_52
407
408config ARCH_SUPPORTS_UPROBES
409	def_bool y
410
411config ARCH_PROC_KCORE_TEXT
412	def_bool y
413
414config BROKEN_GAS_INST
415	def_bool !$(as-instr,1:\n.inst 0\n.rept . - 1b\n\nnop\n.endr\n)
416
417config BUILTIN_RETURN_ADDRESS_STRIPS_PAC
418	bool
419	# Clang's __builtin_return_address() strips the PAC since 12.0.0
420	# https://github.com/llvm/llvm-project/commit/2a96f47c5ffca84cd774ad402cacd137f4bf45e2
421	default y if CC_IS_CLANG
422	# GCC's __builtin_return_address() strips the PAC since 11.1.0,
423	# and this was backported to 10.2.0, 9.4.0, 8.5.0, but not earlier
424	# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94891
425	default y if CC_IS_GCC && (GCC_VERSION >= 110100)
426	default y if CC_IS_GCC && (GCC_VERSION >= 100200) && (GCC_VERSION < 110000)
427	default y if CC_IS_GCC && (GCC_VERSION >=  90400) && (GCC_VERSION < 100000)
428	default y if CC_IS_GCC && (GCC_VERSION >=  80500) && (GCC_VERSION <  90000)
429	default n
430
431config KASAN_SHADOW_OFFSET
432	hex
433	depends on KASAN_GENERIC || KASAN_SW_TAGS
434	default 0xdfff800000000000 if (ARM64_VA_BITS_48 || (ARM64_VA_BITS_52 && !ARM64_16K_PAGES)) && !KASAN_SW_TAGS
435	default 0xdfffc00000000000 if (ARM64_VA_BITS_47 || ARM64_VA_BITS_52) && ARM64_16K_PAGES && !KASAN_SW_TAGS
436	default 0xdffffe0000000000 if ARM64_VA_BITS_42 && !KASAN_SW_TAGS
437	default 0xdfffffc000000000 if ARM64_VA_BITS_39 && !KASAN_SW_TAGS
438	default 0xdffffff800000000 if ARM64_VA_BITS_36 && !KASAN_SW_TAGS
439	default 0xefff800000000000 if (ARM64_VA_BITS_48 || (ARM64_VA_BITS_52 && !ARM64_16K_PAGES)) && KASAN_SW_TAGS
440	default 0xefffc00000000000 if (ARM64_VA_BITS_47 || ARM64_VA_BITS_52) && ARM64_16K_PAGES && KASAN_SW_TAGS
441	default 0xeffffe0000000000 if ARM64_VA_BITS_42 && KASAN_SW_TAGS
442	default 0xefffffc000000000 if ARM64_VA_BITS_39 && KASAN_SW_TAGS
443	default 0xeffffff800000000 if ARM64_VA_BITS_36 && KASAN_SW_TAGS
444	default 0xffffffffffffffff
445
446config UNWIND_TABLES
447	bool
448
449source "arch/arm64/Kconfig.platforms"
450
451menu "Kernel Features"
452
453menu "ARM errata workarounds via the alternatives framework"
454
455config AMPERE_ERRATUM_AC03_CPU_38
456        bool "AmpereOne: AC03_CPU_38: Certain bits in the Virtualization Translation Control Register and Translation Control Registers do not follow RES0 semantics"
457	default y
458	help
459	  This option adds an alternative code sequence to work around Ampere
460	  errata AC03_CPU_38 and AC04_CPU_10 on AmpereOne.
461
462	  The affected design reports FEAT_HAFDBS as not implemented in
463	  ID_AA64MMFR1_EL1.HAFDBS, but (V)TCR_ELx.{HA,HD} are not RES0
464	  as required by the architecture. The unadvertised HAFDBS
465	  implementation suffers from an additional erratum where hardware
466	  A/D updates can occur after a PTE has been marked invalid.
467
468	  The workaround forces KVM to explicitly set VTCR_EL2.HA to 0,
469	  which avoids enabling unadvertised hardware Access Flag management
470	  at stage-2.
471
472	  If unsure, say Y.
473
474config AMPERE_ERRATUM_AC04_CPU_23
475        bool "AmpereOne: AC04_CPU_23:  Failure to synchronize writes to HCR_EL2 may corrupt address translations."
476	default y
477	help
478	  This option adds an alternative code sequence to work around Ampere
479	  errata AC04_CPU_23 on AmpereOne.
480
481	  Updates to HCR_EL2 can rarely corrupt simultaneous translations for
482	  data addresses initiated by load/store instructions. Only
483	  instruction initiated translations are vulnerable, not translations
484	  from prefetches for example. A DSB before the store to HCR_EL2 is
485	  sufficient to prevent older instructions from hitting the window
486	  for corruption, and an ISB after is sufficient to prevent younger
487	  instructions from hitting the window for corruption.
488
489	  If unsure, say Y.
490
491config ARM64_WORKAROUND_CLEAN_CACHE
492	bool
493
494config ARM64_ERRATUM_826319
495	bool "Cortex-A53: 826319: System might deadlock if a write cannot complete until read data is accepted"
496	default y
497	select ARM64_WORKAROUND_CLEAN_CACHE
498	help
499	  This option adds an alternative code sequence to work around ARM
500	  erratum 826319 on Cortex-A53 parts up to r0p2 with an AMBA 4 ACE or
501	  AXI master interface and an L2 cache.
502
503	  If a Cortex-A53 uses an AMBA AXI4 ACE interface to other processors
504	  and is unable to accept a certain write via this interface, it will
505	  not progress on read data presented on the read data channel and the
506	  system can deadlock.
507
508	  The workaround promotes data cache clean instructions to
509	  data cache clean-and-invalidate.
510	  Please note that this does not necessarily enable the workaround,
511	  as it depends on the alternative framework, which will only patch
512	  the kernel if an affected CPU is detected.
513
514	  If unsure, say Y.
515
516config ARM64_ERRATUM_827319
517	bool "Cortex-A53: 827319: Data cache clean instructions might cause overlapping transactions to the interconnect"
518	default y
519	select ARM64_WORKAROUND_CLEAN_CACHE
520	help
521	  This option adds an alternative code sequence to work around ARM
522	  erratum 827319 on Cortex-A53 parts up to r0p2 with an AMBA 5 CHI
523	  master interface and an L2 cache.
524
525	  Under certain conditions this erratum can cause a clean line eviction
526	  to occur at the same time as another transaction to the same address
527	  on the AMBA 5 CHI interface, which can cause data corruption if the
528	  interconnect reorders the two transactions.
529
530	  The workaround promotes data cache clean instructions to
531	  data cache clean-and-invalidate.
532	  Please note that this does not necessarily enable the workaround,
533	  as it depends on the alternative framework, which will only patch
534	  the kernel if an affected CPU is detected.
535
536	  If unsure, say Y.
537
538config ARM64_ERRATUM_824069
539	bool "Cortex-A53: 824069: Cache line might not be marked as clean after a CleanShared snoop"
540	default y
541	select ARM64_WORKAROUND_CLEAN_CACHE
542	help
543	  This option adds an alternative code sequence to work around ARM
544	  erratum 824069 on Cortex-A53 parts up to r0p2 when it is connected
545	  to a coherent interconnect.
546
547	  If a Cortex-A53 processor is executing a store or prefetch for
548	  write instruction at the same time as a processor in another
549	  cluster is executing a cache maintenance operation to the same
550	  address, then this erratum might cause a clean cache line to be
551	  incorrectly marked as dirty.
552
553	  The workaround promotes data cache clean instructions to
554	  data cache clean-and-invalidate.
555	  Please note that this option does not necessarily enable the
556	  workaround, as it depends on the alternative framework, which will
557	  only patch the kernel if an affected CPU is detected.
558
559	  If unsure, say Y.
560
561config ARM64_ERRATUM_819472
562	bool "Cortex-A53: 819472: Store exclusive instructions might cause data corruption"
563	default y
564	select ARM64_WORKAROUND_CLEAN_CACHE
565	help
566	  This option adds an alternative code sequence to work around ARM
567	  erratum 819472 on Cortex-A53 parts up to r0p1 with an L2 cache
568	  present when it is connected to a coherent interconnect.
569
570	  If the processor is executing a load and store exclusive sequence at
571	  the same time as a processor in another cluster is executing a cache
572	  maintenance operation to the same address, then this erratum might
573	  cause data corruption.
574
575	  The workaround promotes data cache clean instructions to
576	  data cache clean-and-invalidate.
577	  Please note that this does not necessarily enable the workaround,
578	  as it depends on the alternative framework, which will only patch
579	  the kernel if an affected CPU is detected.
580
581	  If unsure, say Y.
582
583config ARM64_ERRATUM_832075
584	bool "Cortex-A57: 832075: possible deadlock on mixing exclusive memory accesses with device loads"
585	default y
586	help
587	  This option adds an alternative code sequence to work around ARM
588	  erratum 832075 on Cortex-A57 parts up to r1p2.
589
590	  Affected Cortex-A57 parts might deadlock when exclusive load/store
591	  instructions to Write-Back memory are mixed with Device loads.
592
593	  The workaround is to promote device loads to use Load-Acquire
594	  semantics.
595	  Please note that this does not necessarily enable the workaround,
596	  as it depends on the alternative framework, which will only patch
597	  the kernel if an affected CPU is detected.
598
599	  If unsure, say Y.
600
601config ARM64_ERRATUM_834220
602	bool "Cortex-A57: 834220: Stage 2 translation fault might be incorrectly reported in presence of a Stage 1 fault (rare)"
603	depends on KVM
604	help
605	  This option adds an alternative code sequence to work around ARM
606	  erratum 834220 on Cortex-A57 parts up to r1p2.
607
608	  Affected Cortex-A57 parts might report a Stage 2 translation
609	  fault as the result of a Stage 1 fault for load crossing a
610	  page boundary when there is a permission or device memory
611	  alignment fault at Stage 1 and a translation fault at Stage 2.
612
613	  The workaround is to verify that the Stage 1 translation
614	  doesn't generate a fault before handling the Stage 2 fault.
615	  Please note that this does not necessarily enable the workaround,
616	  as it depends on the alternative framework, which will only patch
617	  the kernel if an affected CPU is detected.
618
619	  If unsure, say N.
620
621config ARM64_ERRATUM_1742098
622	bool "Cortex-A57/A72: 1742098: ELR recorded incorrectly on interrupt taken between cryptographic instructions in a sequence"
623	depends on COMPAT
624	default y
625	help
626	  This option removes the AES hwcap for aarch32 user-space to
627	  workaround erratum 1742098 on Cortex-A57 and Cortex-A72.
628
629	  Affected parts may corrupt the AES state if an interrupt is
630	  taken between a pair of AES instructions. These instructions
631	  are only present if the cryptography extensions are present.
632	  All software should have a fallback implementation for CPUs
633	  that don't implement the cryptography extensions.
634
635	  If unsure, say Y.
636
637config ARM64_ERRATUM_845719
638	bool "Cortex-A53: 845719: a load might read incorrect data"
639	depends on COMPAT
640	default y
641	help
642	  This option adds an alternative code sequence to work around ARM
643	  erratum 845719 on Cortex-A53 parts up to r0p4.
644
645	  When running a compat (AArch32) userspace on an affected Cortex-A53
646	  part, a load at EL0 from a virtual address that matches the bottom 32
647	  bits of the virtual address used by a recent load at (AArch64) EL1
648	  might return incorrect data.
649
650	  The workaround is to write the contextidr_el1 register on exception
651	  return to a 32-bit task.
652	  Please note that this does not necessarily enable the workaround,
653	  as it depends on the alternative framework, which will only patch
654	  the kernel if an affected CPU is detected.
655
656	  If unsure, say Y.
657
658config ARM64_ERRATUM_843419
659	bool "Cortex-A53: 843419: A load or store might access an incorrect address"
660	default y
661	help
662	  This option links the kernel with '--fix-cortex-a53-843419' and
663	  enables PLT support to replace certain ADRP instructions, which can
664	  cause subsequent memory accesses to use an incorrect address on
665	  Cortex-A53 parts up to r0p4.
666
667	  If unsure, say Y.
668
669config ARM64_ERRATUM_1024718
670	bool "Cortex-A55: 1024718: Update of DBM/AP bits without break before make might result in incorrect update"
671	default y
672	help
673	  This option adds a workaround for ARM Cortex-A55 Erratum 1024718.
674
675	  Affected Cortex-A55 cores (all revisions) could cause incorrect
676	  update of the hardware dirty bit when the DBM/AP bits are updated
677	  without a break-before-make. The workaround is to disable the usage
678	  of hardware DBM locally on the affected cores. CPUs not affected by
679	  this erratum will continue to use the feature.
680
681	  If unsure, say Y.
682
683config ARM64_ERRATUM_1418040
684	bool "Cortex-A76/Neoverse-N1: MRC read following MRRC read of specific Generic Timer in AArch32 might give incorrect result"
685	default y
686	depends on COMPAT
687	help
688	  This option adds a workaround for ARM Cortex-A76/Neoverse-N1
689	  errata 1188873 and 1418040.
690
691	  Affected Cortex-A76/Neoverse-N1 cores (r0p0 to r3p1) could
692	  cause register corruption when accessing the timer registers
693	  from AArch32 userspace.
694
695	  If unsure, say Y.
696
697config ARM64_WORKAROUND_SPECULATIVE_AT
698	bool
699
700config ARM64_ERRATUM_1165522
701	bool "Cortex-A76: 1165522: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
702	default y
703	select ARM64_WORKAROUND_SPECULATIVE_AT
704	help
705	  This option adds a workaround for ARM Cortex-A76 erratum 1165522.
706
707	  Affected Cortex-A76 cores (r0p0, r1p0, r2p0) could end-up with
708	  corrupted TLBs by speculating an AT instruction during a guest
709	  context switch.
710
711	  If unsure, say Y.
712
713config ARM64_ERRATUM_1319367
714	bool "Cortex-A57/A72: 1319537: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
715	default y
716	select ARM64_WORKAROUND_SPECULATIVE_AT
717	help
718	  This option adds work arounds for ARM Cortex-A57 erratum 1319537
719	  and A72 erratum 1319367
720
721	  Cortex-A57 and A72 cores could end-up with corrupted TLBs by
722	  speculating an AT instruction during a guest context switch.
723
724	  If unsure, say Y.
725
726config ARM64_ERRATUM_1530923
727	bool "Cortex-A55: 1530923: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
728	default y
729	select ARM64_WORKAROUND_SPECULATIVE_AT
730	help
731	  This option adds a workaround for ARM Cortex-A55 erratum 1530923.
732
733	  Affected Cortex-A55 cores (r0p0, r0p1, r1p0, r2p0) could end-up with
734	  corrupted TLBs by speculating an AT instruction during a guest
735	  context switch.
736
737	  If unsure, say Y.
738
739config ARM64_WORKAROUND_REPEAT_TLBI
740	bool
741
742config ARM64_ERRATUM_2441007
743	bool "Cortex-A55: Completion of affected memory accesses might not be guaranteed by completion of a TLBI (rare)"
744	select ARM64_WORKAROUND_REPEAT_TLBI
745	help
746	  This option adds a workaround for ARM Cortex-A55 erratum #2441007.
747
748	  Under very rare circumstances, affected Cortex-A55 CPUs
749	  may not handle a race between a break-before-make sequence on one
750	  CPU, and another CPU accessing the same page. This could allow a
751	  store to a page that has been unmapped.
752
753	  Work around this by adding the affected CPUs to the list that needs
754	  TLB sequences to be done twice.
755
756	  If unsure, say N.
757
758config ARM64_ERRATUM_1286807
759	bool "Cortex-A76: Modification of the translation table for a virtual address might lead to read-after-read ordering violation (rare)"
760	select ARM64_WORKAROUND_REPEAT_TLBI
761	help
762	  This option adds a workaround for ARM Cortex-A76 erratum 1286807.
763
764	  On the affected Cortex-A76 cores (r0p0 to r3p0), if a virtual
765	  address for a cacheable mapping of a location is being
766	  accessed by a core while another core is remapping the virtual
767	  address to a new physical page using the recommended
768	  break-before-make sequence, then under very rare circumstances
769	  TLBI+DSB completes before a read using the translation being
770	  invalidated has been observed by other observers. The
771	  workaround repeats the TLBI+DSB operation.
772
773	  If unsure, say N.
774
775config ARM64_ERRATUM_1463225
776	bool "Cortex-A76: Software Step might prevent interrupt recognition"
777	default y
778	help
779	  This option adds a workaround for Arm Cortex-A76 erratum 1463225.
780
781	  On the affected Cortex-A76 cores (r0p0 to r3p1), software stepping
782	  of a system call instruction (SVC) can prevent recognition of
783	  subsequent interrupts when software stepping is disabled in the
784	  exception handler of the system call and either kernel debugging
785	  is enabled or VHE is in use.
786
787	  Work around the erratum by triggering a dummy step exception
788	  when handling a system call from a task that is being stepped
789	  in a VHE configuration of the kernel.
790
791	  If unsure, say Y.
792
793config ARM64_ERRATUM_1542419
794	bool "Neoverse-N1: workaround mis-ordering of instruction fetches (rare)"
795	help
796	  This option adds a workaround for ARM Neoverse-N1 erratum
797	  1542419.
798
799	  Affected Neoverse-N1 cores could execute a stale instruction when
800	  modified by another CPU. The workaround depends on a firmware
801	  counterpart.
802
803	  Workaround the issue by hiding the DIC feature from EL0. This
804	  forces user-space to perform cache maintenance.
805
806	  If unsure, say N.
807
808config ARM64_ERRATUM_1508412
809	bool "Cortex-A77: 1508412: workaround deadlock on sequence of NC/Device load and store exclusive or PAR read"
810	default y
811	help
812	  This option adds a workaround for Arm Cortex-A77 erratum 1508412.
813
814	  Affected Cortex-A77 cores (r0p0, r1p0) could deadlock on a sequence
815	  of a store-exclusive or read of PAR_EL1 and a load with device or
816	  non-cacheable memory attributes. The workaround depends on a firmware
817	  counterpart.
818
819	  KVM guests must also have the workaround implemented or they can
820	  deadlock the system.
821
822	  Work around the issue by inserting DMB SY barriers around PAR_EL1
823	  register reads and warning KVM users. The DMB barrier is sufficient
824	  to prevent a speculative PAR_EL1 read.
825
826	  If unsure, say Y.
827
828config ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
829	bool
830
831config ARM64_ERRATUM_2051678
832	bool "Cortex-A510: 2051678: disable Hardware Update of the page table dirty bit"
833	default y
834	help
835	  This options adds the workaround for ARM Cortex-A510 erratum ARM64_ERRATUM_2051678.
836	  Affected Cortex-A510 might not respect the ordering rules for
837	  hardware update of the page table's dirty bit. The workaround
838	  is to not enable the feature on affected CPUs.
839
840	  If unsure, say Y.
841
842config ARM64_ERRATUM_2077057
843	bool "Cortex-A510: 2077057: workaround software-step corrupting SPSR_EL2"
844	default y
845	help
846	  This option adds the workaround for ARM Cortex-A510 erratum 2077057.
847	  Affected Cortex-A510 may corrupt SPSR_EL2 when the a step exception is
848	  expected, but a Pointer Authentication trap is taken instead. The
849	  erratum causes SPSR_EL1 to be copied to SPSR_EL2, which could allow
850	  EL1 to cause a return to EL2 with a guest controlled ELR_EL2.
851
852	  This can only happen when EL2 is stepping EL1.
853
854	  When these conditions occur, the SPSR_EL2 value is unchanged from the
855	  previous guest entry, and can be restored from the in-memory copy.
856
857	  If unsure, say Y.
858
859config ARM64_ERRATUM_2658417
860	bool "Cortex-A510: 2658417: remove BF16 support due to incorrect result"
861	default y
862	help
863	  This option adds the workaround for ARM Cortex-A510 erratum 2658417.
864	  Affected Cortex-A510 (r0p0 to r1p1) may produce the wrong result for
865	  BFMMLA or VMMLA instructions in rare circumstances when a pair of
866	  A510 CPUs are using shared neon hardware. As the sharing is not
867	  discoverable by the kernel, hide the BF16 HWCAP to indicate that
868	  user-space should not be using these instructions.
869
870	  If unsure, say Y.
871
872config ARM64_ERRATUM_2119858
873	bool "Cortex-A710/X2: 2119858: workaround TRBE overwriting trace data in FILL mode"
874	default y
875	depends on CORESIGHT_TRBE
876	select ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
877	help
878	  This option adds the workaround for ARM Cortex-A710/X2 erratum 2119858.
879
880	  Affected Cortex-A710/X2 cores could overwrite up to 3 cache lines of trace
881	  data at the base of the buffer (pointed to by TRBASER_EL1) in FILL mode in
882	  the event of a WRAP event.
883
884	  Work around the issue by always making sure we move the TRBPTR_EL1 by
885	  256 bytes before enabling the buffer and filling the first 256 bytes of
886	  the buffer with ETM ignore packets upon disabling.
887
888	  If unsure, say Y.
889
890config ARM64_ERRATUM_2139208
891	bool "Neoverse-N2: 2139208: workaround TRBE overwriting trace data in FILL mode"
892	default y
893	depends on CORESIGHT_TRBE
894	select ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
895	help
896	  This option adds the workaround for ARM Neoverse-N2 erratum 2139208.
897
898	  Affected Neoverse-N2 cores could overwrite up to 3 cache lines of trace
899	  data at the base of the buffer (pointed to by TRBASER_EL1) in FILL mode in
900	  the event of a WRAP event.
901
902	  Work around the issue by always making sure we move the TRBPTR_EL1 by
903	  256 bytes before enabling the buffer and filling the first 256 bytes of
904	  the buffer with ETM ignore packets upon disabling.
905
906	  If unsure, say Y.
907
908config ARM64_WORKAROUND_TSB_FLUSH_FAILURE
909	bool
910
911config ARM64_ERRATUM_2054223
912	bool "Cortex-A710: 2054223: workaround TSB instruction failing to flush trace"
913	default y
914	select ARM64_WORKAROUND_TSB_FLUSH_FAILURE
915	help
916	  Enable workaround for ARM Cortex-A710 erratum 2054223
917
918	  Affected cores may fail to flush the trace data on a TSB instruction, when
919	  the PE is in trace prohibited state. This will cause losing a few bytes
920	  of the trace cached.
921
922	  Workaround is to issue two TSB consecutively on affected cores.
923
924	  If unsure, say Y.
925
926config ARM64_ERRATUM_2067961
927	bool "Neoverse-N2: 2067961: workaround TSB instruction failing to flush trace"
928	default y
929	select ARM64_WORKAROUND_TSB_FLUSH_FAILURE
930	help
931	  Enable workaround for ARM Neoverse-N2 erratum 2067961
932
933	  Affected cores may fail to flush the trace data on a TSB instruction, when
934	  the PE is in trace prohibited state. This will cause losing a few bytes
935	  of the trace cached.
936
937	  Workaround is to issue two TSB consecutively on affected cores.
938
939	  If unsure, say Y.
940
941config ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE
942	bool
943
944config ARM64_ERRATUM_2253138
945	bool "Neoverse-N2: 2253138: workaround TRBE writing to address out-of-range"
946	depends on CORESIGHT_TRBE
947	default y
948	select ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE
949	help
950	  This option adds the workaround for ARM Neoverse-N2 erratum 2253138.
951
952	  Affected Neoverse-N2 cores might write to an out-of-range address, not reserved
953	  for TRBE. Under some conditions, the TRBE might generate a write to the next
954	  virtually addressed page following the last page of the TRBE address space
955	  (i.e., the TRBLIMITR_EL1.LIMIT), instead of wrapping around to the base.
956
957	  Work around this in the driver by always making sure that there is a
958	  page beyond the TRBLIMITR_EL1.LIMIT, within the space allowed for the TRBE.
959
960	  If unsure, say Y.
961
962config ARM64_ERRATUM_2224489
963	bool "Cortex-A710/X2: 2224489: workaround TRBE writing to address out-of-range"
964	depends on CORESIGHT_TRBE
965	default y
966	select ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE
967	help
968	  This option adds the workaround for ARM Cortex-A710/X2 erratum 2224489.
969
970	  Affected Cortex-A710/X2 cores might write to an out-of-range address, not reserved
971	  for TRBE. Under some conditions, the TRBE might generate a write to the next
972	  virtually addressed page following the last page of the TRBE address space
973	  (i.e., the TRBLIMITR_EL1.LIMIT), instead of wrapping around to the base.
974
975	  Work around this in the driver by always making sure that there is a
976	  page beyond the TRBLIMITR_EL1.LIMIT, within the space allowed for the TRBE.
977
978	  If unsure, say Y.
979
980config ARM64_ERRATUM_2441009
981	bool "Cortex-A510: Completion of affected memory accesses might not be guaranteed by completion of a TLBI (rare)"
982	select ARM64_WORKAROUND_REPEAT_TLBI
983	help
984	  This option adds a workaround for ARM Cortex-A510 erratum #2441009.
985
986	  Under very rare circumstances, affected Cortex-A510 CPUs
987	  may not handle a race between a break-before-make sequence on one
988	  CPU, and another CPU accessing the same page. This could allow a
989	  store to a page that has been unmapped.
990
991	  Work around this by adding the affected CPUs to the list that needs
992	  TLB sequences to be done twice.
993
994	  If unsure, say N.
995
996config ARM64_ERRATUM_2064142
997	bool "Cortex-A510: 2064142: workaround TRBE register writes while disabled"
998	depends on CORESIGHT_TRBE
999	default y
1000	help
1001	  This option adds the workaround for ARM Cortex-A510 erratum 2064142.
1002
1003	  Affected Cortex-A510 core might fail to write into system registers after the
1004	  TRBE has been disabled. Under some conditions after the TRBE has been disabled
1005	  writes into TRBE registers TRBLIMITR_EL1, TRBPTR_EL1, TRBBASER_EL1, TRBSR_EL1,
1006	  and TRBTRG_EL1 will be ignored and will not be effected.
1007
1008	  Work around this in the driver by executing TSB CSYNC and DSB after collection
1009	  is stopped and before performing a system register write to one of the affected
1010	  registers.
1011
1012	  If unsure, say Y.
1013
1014config ARM64_ERRATUM_2038923
1015	bool "Cortex-A510: 2038923: workaround TRBE corruption with enable"
1016	depends on CORESIGHT_TRBE
1017	default y
1018	help
1019	  This option adds the workaround for ARM Cortex-A510 erratum 2038923.
1020
1021	  Affected Cortex-A510 core might cause an inconsistent view on whether trace is
1022	  prohibited within the CPU. As a result, the trace buffer or trace buffer state
1023	  might be corrupted. This happens after TRBE buffer has been enabled by setting
1024	  TRBLIMITR_EL1.E, followed by just a single context synchronization event before
1025	  execution changes from a context, in which trace is prohibited to one where it
1026	  isn't, or vice versa. In these mentioned conditions, the view of whether trace
1027	  is prohibited is inconsistent between parts of the CPU, and the trace buffer or
1028	  the trace buffer state might be corrupted.
1029
1030	  Work around this in the driver by preventing an inconsistent view of whether the
1031	  trace is prohibited or not based on TRBLIMITR_EL1.E by immediately following a
1032	  change to TRBLIMITR_EL1.E with at least one ISB instruction before an ERET, or
1033	  two ISB instructions if no ERET is to take place.
1034
1035	  If unsure, say Y.
1036
1037config ARM64_ERRATUM_1902691
1038	bool "Cortex-A510: 1902691: workaround TRBE trace corruption"
1039	depends on CORESIGHT_TRBE
1040	default y
1041	help
1042	  This option adds the workaround for ARM Cortex-A510 erratum 1902691.
1043
1044	  Affected Cortex-A510 core might cause trace data corruption, when being written
1045	  into the memory. Effectively TRBE is broken and hence cannot be used to capture
1046	  trace data.
1047
1048	  Work around this problem in the driver by just preventing TRBE initialization on
1049	  affected cpus. The firmware must have disabled the access to TRBE for the kernel
1050	  on such implementations. This will cover the kernel for any firmware that doesn't
1051	  do this already.
1052
1053	  If unsure, say Y.
1054
1055config ARM64_ERRATUM_2457168
1056	bool "Cortex-A510: 2457168: workaround for AMEVCNTR01 incrementing incorrectly"
1057	depends on ARM64_AMU_EXTN
1058	default y
1059	help
1060	  This option adds the workaround for ARM Cortex-A510 erratum 2457168.
1061
1062	  The AMU counter AMEVCNTR01 (constant counter) should increment at the same rate
1063	  as the system counter. On affected Cortex-A510 cores AMEVCNTR01 increments
1064	  incorrectly giving a significantly higher output value.
1065
1066	  Work around this problem by returning 0 when reading the affected counter in
1067	  key locations that results in disabling all users of this counter. This effect
1068	  is the same to firmware disabling affected counters.
1069
1070	  If unsure, say Y.
1071
1072config ARM64_ERRATUM_2645198
1073	bool "Cortex-A715: 2645198: Workaround possible [ESR|FAR]_ELx corruption"
1074	default y
1075	help
1076	  This option adds the workaround for ARM Cortex-A715 erratum 2645198.
1077
1078	  If a Cortex-A715 cpu sees a page mapping permissions change from executable
1079	  to non-executable, it may corrupt the ESR_ELx and FAR_ELx registers on the
1080	  next instruction abort caused by permission fault.
1081
1082	  Only user-space does executable to non-executable permission transition via
1083	  mprotect() system call. Workaround the problem by doing a break-before-make
1084	  TLB invalidation, for all changes to executable user space mappings.
1085
1086	  If unsure, say Y.
1087
1088config ARM64_WORKAROUND_SPECULATIVE_UNPRIV_LOAD
1089	bool
1090
1091config ARM64_ERRATUM_2966298
1092	bool "Cortex-A520: 2966298: workaround for speculatively executed unprivileged load"
1093	select ARM64_WORKAROUND_SPECULATIVE_UNPRIV_LOAD
1094	default y
1095	help
1096	  This option adds the workaround for ARM Cortex-A520 erratum 2966298.
1097
1098	  On an affected Cortex-A520 core, a speculatively executed unprivileged
1099	  load might leak data from a privileged level via a cache side channel.
1100
1101	  Work around this problem by executing a TLBI before returning to EL0.
1102
1103	  If unsure, say Y.
1104
1105config ARM64_ERRATUM_3117295
1106	bool "Cortex-A510: 3117295: workaround for speculatively executed unprivileged load"
1107	select ARM64_WORKAROUND_SPECULATIVE_UNPRIV_LOAD
1108	default y
1109	help
1110	  This option adds the workaround for ARM Cortex-A510 erratum 3117295.
1111
1112	  On an affected Cortex-A510 core, a speculatively executed unprivileged
1113	  load might leak data from a privileged level via a cache side channel.
1114
1115	  Work around this problem by executing a TLBI before returning to EL0.
1116
1117	  If unsure, say Y.
1118
1119config ARM64_ERRATUM_3194386
1120	bool "Cortex-*/Neoverse-*: workaround for MSR SSBS not self-synchronizing"
1121	default y
1122	help
1123	  This option adds the workaround for the following errata:
1124
1125	  * ARM Cortex-A76 erratum 3324349
1126	  * ARM Cortex-A77 erratum 3324348
1127	  * ARM Cortex-A78 erratum 3324344
1128	  * ARM Cortex-A78C erratum 3324346
1129	  * ARM Cortex-A78C erratum 3324347
1130	  * ARM Cortex-A710 erratam 3324338
1131	  * ARM Cortex-A715 errartum 3456084
1132	  * ARM Cortex-A720 erratum 3456091
1133	  * ARM Cortex-A725 erratum 3456106
1134	  * ARM Cortex-X1 erratum 3324344
1135	  * ARM Cortex-X1C erratum 3324346
1136	  * ARM Cortex-X2 erratum 3324338
1137	  * ARM Cortex-X3 erratum 3324335
1138	  * ARM Cortex-X4 erratum 3194386
1139	  * ARM Cortex-X925 erratum 3324334
1140	  * ARM Neoverse-N1 erratum 3324349
1141	  * ARM Neoverse N2 erratum 3324339
1142	  * ARM Neoverse-N3 erratum 3456111
1143	  * ARM Neoverse-V1 erratum 3324341
1144	  * ARM Neoverse V2 erratum 3324336
1145	  * ARM Neoverse-V3 erratum 3312417
1146	  * ARM Neoverse-V3AE erratum 3312417
1147
1148	  On affected cores "MSR SSBS, #0" instructions may not affect
1149	  subsequent speculative instructions, which may permit unexepected
1150	  speculative store bypassing.
1151
1152	  Work around this problem by placing a Speculation Barrier (SB) or
1153	  Instruction Synchronization Barrier (ISB) after kernel changes to
1154	  SSBS. The presence of the SSBS special-purpose register is hidden
1155	  from hwcaps and EL0 reads of ID_AA64PFR1_EL1, such that userspace
1156	  will use the PR_SPEC_STORE_BYPASS prctl to change SSBS.
1157
1158	  If unsure, say Y.
1159
1160config ARM64_ERRATUM_4311569
1161	bool "SI L1: 4311569: workaround for premature CMO completion erratum"
1162	default y
1163	help
1164	  This option adds the workaround for ARM SI L1 erratum 4311569.
1165
1166	  The erratum of SI L1 can cause an early response to a combined write
1167	  and cache maintenance operation (WR+CMO) before the operation is fully
1168	  completed to the Point of Serialization (POS).
1169	  This can result in a non-I/O coherent agent observing stale data,
1170	  potentially leading to system instability or incorrect behavior.
1171
1172	  Enabling this option implements a software workaround by inserting a
1173	  second loop of Cache Maintenance Operation (CMO) immediately following the
1174	  end of function to do CMOs. This ensures that the data is correctly serialized
1175	  before the buffer is handed off to a non-coherent agent.
1176
1177	  If unsure, say Y.
1178
1179config CAVIUM_ERRATUM_22375
1180	bool "Cavium erratum 22375, 24313"
1181	default y
1182	help
1183	  Enable workaround for errata 22375 and 24313.
1184
1185	  This implements two gicv3-its errata workarounds for ThunderX. Both
1186	  with a small impact affecting only ITS table allocation.
1187
1188	    erratum 22375: only alloc 8MB table size
1189	    erratum 24313: ignore memory access type
1190
1191	  The fixes are in ITS initialization and basically ignore memory access
1192	  type and table size provided by the TYPER and BASER registers.
1193
1194	  If unsure, say Y.
1195
1196config CAVIUM_ERRATUM_23144
1197	bool "Cavium erratum 23144: ITS SYNC hang on dual socket system"
1198	depends on NUMA
1199	default y
1200	help
1201	  ITS SYNC command hang for cross node io and collections/cpu mapping.
1202
1203	  If unsure, say Y.
1204
1205config CAVIUM_ERRATUM_23154
1206	bool "Cavium errata 23154 and 38545: GICv3 lacks HW synchronisation"
1207	default y
1208	help
1209	  The ThunderX GICv3 implementation requires a modified version for
1210	  reading the IAR status to ensure data synchronization
1211	  (access to icc_iar1_el1 is not sync'ed before and after).
1212
1213	  It also suffers from erratum 38545 (also present on Marvell's
1214	  OcteonTX and OcteonTX2), resulting in deactivated interrupts being
1215	  spuriously presented to the CPU interface.
1216
1217	  If unsure, say Y.
1218
1219config CAVIUM_ERRATUM_27456
1220	bool "Cavium erratum 27456: Broadcast TLBI instructions may cause icache corruption"
1221	default y
1222	help
1223	  On ThunderX T88 pass 1.x through 2.1 parts, broadcast TLBI
1224	  instructions may cause the icache to become corrupted if it
1225	  contains data for a non-current ASID.  The fix is to
1226	  invalidate the icache when changing the mm context.
1227
1228	  If unsure, say Y.
1229
1230config CAVIUM_ERRATUM_30115
1231	bool "Cavium erratum 30115: Guest may disable interrupts in host"
1232	default y
1233	help
1234	  On ThunderX T88 pass 1.x through 2.2, T81 pass 1.0 through
1235	  1.2, and T83 Pass 1.0, KVM guest execution may disable
1236	  interrupts in host. Trapping both GICv3 group-0 and group-1
1237	  accesses sidesteps the issue.
1238
1239	  If unsure, say Y.
1240
1241config CAVIUM_TX2_ERRATUM_219
1242	bool "Cavium ThunderX2 erratum 219: PRFM between TTBR change and ISB fails"
1243	default y
1244	help
1245	  On Cavium ThunderX2, a load, store or prefetch instruction between a
1246	  TTBR update and the corresponding context synchronizing operation can
1247	  cause a spurious Data Abort to be delivered to any hardware thread in
1248	  the CPU core.
1249
1250	  Work around the issue by avoiding the problematic code sequence and
1251	  trapping KVM guest TTBRx_EL1 writes to EL2 when SMT is enabled. The
1252	  trap handler performs the corresponding register access, skips the
1253	  instruction and ensures context synchronization by virtue of the
1254	  exception return.
1255
1256	  If unsure, say Y.
1257
1258config FUJITSU_ERRATUM_010001
1259	bool "Fujitsu-A64FX erratum E#010001: Undefined fault may occur wrongly"
1260	default y
1261	help
1262	  This option adds a workaround for Fujitsu-A64FX erratum E#010001.
1263	  On some variants of the Fujitsu-A64FX cores ver(1.0, 1.1), memory
1264	  accesses may cause undefined fault (Data abort, DFSC=0b111111).
1265	  This fault occurs under a specific hardware condition when a
1266	  load/store instruction performs an address translation using:
1267	  case-1  TTBR0_EL1 with TCR_EL1.NFD0 == 1.
1268	  case-2  TTBR0_EL2 with TCR_EL2.NFD0 == 1.
1269	  case-3  TTBR1_EL1 with TCR_EL1.NFD1 == 1.
1270	  case-4  TTBR1_EL2 with TCR_EL2.NFD1 == 1.
1271
1272	  The workaround is to ensure these bits are clear in TCR_ELx.
1273	  The workaround only affects the Fujitsu-A64FX.
1274
1275	  If unsure, say Y.
1276
1277config HISILICON_ERRATUM_161600802
1278	bool "Hip07 161600802: Erroneous redistributor VLPI base"
1279	default y
1280	help
1281	  The HiSilicon Hip07 SoC uses the wrong redistributor base
1282	  when issued ITS commands such as VMOVP and VMAPP, and requires
1283	  a 128kB offset to be applied to the target address in this commands.
1284
1285	  If unsure, say Y.
1286
1287config HISILICON_ERRATUM_162100801
1288	bool "Hip09 162100801 erratum support"
1289	default y
1290	help
1291	  When enabling GICv4.1 in hip09, VMAPP will fail to clear some caches
1292	  during unmapping operation, which will cause some vSGIs lost.
1293	  To fix the issue, invalidate related vPE cache through GICR_INVALLR
1294	  after VMOVP.
1295
1296	  If unsure, say Y.
1297
1298config QCOM_FALKOR_ERRATUM_1003
1299	bool "Falkor E1003: Incorrect translation due to ASID change"
1300	default y
1301	help
1302	  On Falkor v1, an incorrect ASID may be cached in the TLB when ASID
1303	  and BADDR are changed together in TTBRx_EL1. Since we keep the ASID
1304	  in TTBR1_EL1, this situation only occurs in the entry trampoline and
1305	  then only for entries in the walk cache, since the leaf translation
1306	  is unchanged. Work around the erratum by invalidating the walk cache
1307	  entries for the trampoline before entering the kernel proper.
1308
1309config QCOM_FALKOR_ERRATUM_1009
1310	bool "Falkor E1009: Prematurely complete a DSB after a TLBI"
1311	default y
1312	select ARM64_WORKAROUND_REPEAT_TLBI
1313	help
1314	  On Falkor v1, the CPU may prematurely complete a DSB following a
1315	  TLBI xxIS invalidate maintenance operation. Repeat the TLBI operation
1316	  one more time to fix the issue.
1317
1318	  If unsure, say Y.
1319
1320config QCOM_QDF2400_ERRATUM_0065
1321	bool "QDF2400 E0065: Incorrect GITS_TYPER.ITT_Entry_size"
1322	default y
1323	help
1324	  On Qualcomm Datacenter Technologies QDF2400 SoC, ITS hardware reports
1325	  ITE size incorrectly. The GITS_TYPER.ITT_Entry_size field should have
1326	  been indicated as 16Bytes (0xf), not 8Bytes (0x7).
1327
1328	  If unsure, say Y.
1329
1330config QCOM_FALKOR_ERRATUM_E1041
1331	bool "Falkor E1041: Speculative instruction fetches might cause errant memory access"
1332	default y
1333	help
1334	  Falkor CPU may speculatively fetch instructions from an improper
1335	  memory location when MMU translation is changed from SCTLR_ELn[M]=1
1336	  to SCTLR_ELn[M]=0. Prefix an ISB instruction to fix the problem.
1337
1338	  If unsure, say Y.
1339
1340config NVIDIA_CARMEL_CNP_ERRATUM
1341	bool "NVIDIA Carmel CNP: CNP on Carmel semantically different than ARM cores"
1342	default y
1343	help
1344	  If CNP is enabled on Carmel cores, non-sharable TLBIs on a core will not
1345	  invalidate shared TLB entries installed by a different core, as it would
1346	  on standard ARM cores.
1347
1348	  If unsure, say Y.
1349
1350config ROCKCHIP_ERRATUM_3568002
1351	bool "Rockchip 3568002: GIC600 can not access physical addresses higher than 4GB"
1352	default y
1353	help
1354	  The Rockchip RK3566 and RK3568 GIC600 SoC integrations have AXI
1355	  addressing limited to the first 32bit of physical address space.
1356
1357	  If unsure, say Y.
1358
1359config ROCKCHIP_ERRATUM_3588001
1360	bool "Rockchip 3588001: GIC600 can not support shareability attributes"
1361	default y
1362	help
1363	  The Rockchip RK3588 GIC600 SoC integration does not support ACE/ACE-lite.
1364	  This means, that its sharability feature may not be used, even though it
1365	  is supported by the IP itself.
1366
1367	  If unsure, say Y.
1368
1369config SOCIONEXT_SYNQUACER_PREITS
1370	bool "Socionext Synquacer: Workaround for GICv3 pre-ITS"
1371	default y
1372	help
1373	  Socionext Synquacer SoCs implement a separate h/w block to generate
1374	  MSI doorbell writes with non-zero values for the device ID.
1375
1376	  If unsure, say Y.
1377
1378endmenu # "ARM errata workarounds via the alternatives framework"
1379
1380choice
1381	prompt "Page size"
1382	default ARM64_4K_PAGES
1383	help
1384	  Page size (translation granule) configuration.
1385
1386config ARM64_4K_PAGES
1387	bool "4KB"
1388	select HAVE_PAGE_SIZE_4KB
1389	help
1390	  This feature enables 4KB pages support.
1391
1392config ARM64_16K_PAGES
1393	bool "16KB"
1394	select HAVE_PAGE_SIZE_16KB
1395	help
1396	  The system will use 16KB pages support. AArch32 emulation
1397	  requires applications compiled with 16K (or a multiple of 16K)
1398	  aligned segments.
1399
1400config ARM64_64K_PAGES
1401	bool "64KB"
1402	select HAVE_PAGE_SIZE_64KB
1403	help
1404	  This feature enables 64KB pages support (4KB by default)
1405	  allowing only two levels of page tables and faster TLB
1406	  look-up. AArch32 emulation requires applications compiled
1407	  with 64K aligned segments.
1408
1409endchoice
1410
1411choice
1412	prompt "Virtual address space size"
1413	default ARM64_VA_BITS_52
1414	help
1415	  Allows choosing one of multiple possible virtual address
1416	  space sizes. The level of translation table is determined by
1417	  a combination of page size and virtual address space size.
1418
1419config ARM64_VA_BITS_36
1420	bool "36-bit" if EXPERT
1421	depends on PAGE_SIZE_16KB
1422
1423config ARM64_VA_BITS_39
1424	bool "39-bit"
1425	depends on PAGE_SIZE_4KB
1426
1427config ARM64_VA_BITS_42
1428	bool "42-bit"
1429	depends on PAGE_SIZE_64KB
1430
1431config ARM64_VA_BITS_47
1432	bool "47-bit"
1433	depends on PAGE_SIZE_16KB
1434
1435config ARM64_VA_BITS_48
1436	bool "48-bit"
1437
1438config ARM64_VA_BITS_52
1439	bool "52-bit"
1440	help
1441	  Enable 52-bit virtual addressing for userspace when explicitly
1442	  requested via a hint to mmap(). The kernel will also use 52-bit
1443	  virtual addresses for its own mappings (provided HW support for
1444	  this feature is available, otherwise it reverts to 48-bit).
1445
1446	  NOTE: Enabling 52-bit virtual addressing in conjunction with
1447	  ARMv8.3 Pointer Authentication will result in the PAC being
1448	  reduced from 7 bits to 3 bits, which may have a significant
1449	  impact on its susceptibility to brute-force attacks.
1450
1451	  If unsure, select 48-bit virtual addressing instead.
1452
1453endchoice
1454
1455config ARM64_FORCE_52BIT
1456	bool "Force 52-bit virtual addresses for userspace"
1457	depends on ARM64_VA_BITS_52 && EXPERT
1458	help
1459	  For systems with 52-bit userspace VAs enabled, the kernel will attempt
1460	  to maintain compatibility with older software by providing 48-bit VAs
1461	  unless a hint is supplied to mmap.
1462
1463	  This configuration option disables the 48-bit compatibility logic, and
1464	  forces all userspace addresses to be 52-bit on HW that supports it. One
1465	  should only enable this configuration option for stress testing userspace
1466	  memory management code. If unsure say N here.
1467
1468config ARM64_VA_BITS
1469	int
1470	default 36 if ARM64_VA_BITS_36
1471	default 39 if ARM64_VA_BITS_39
1472	default 42 if ARM64_VA_BITS_42
1473	default 47 if ARM64_VA_BITS_47
1474	default 48 if ARM64_VA_BITS_48
1475	default 52 if ARM64_VA_BITS_52
1476
1477choice
1478	prompt "Physical address space size"
1479	default ARM64_PA_BITS_48
1480	help
1481	  Choose the maximum physical address range that the kernel will
1482	  support.
1483
1484config ARM64_PA_BITS_48
1485	bool "48-bit"
1486	depends on ARM64_64K_PAGES || !ARM64_VA_BITS_52
1487
1488config ARM64_PA_BITS_52
1489	bool "52-bit"
1490	depends on ARM64_64K_PAGES || ARM64_VA_BITS_52
1491	help
1492	  Enable support for a 52-bit physical address space, introduced as
1493	  part of the ARMv8.2-LPA extension.
1494
1495	  With this enabled, the kernel will also continue to work on CPUs that
1496	  do not support ARMv8.2-LPA, but with some added memory overhead (and
1497	  minor performance overhead).
1498
1499endchoice
1500
1501config ARM64_PA_BITS
1502	int
1503	default 48 if ARM64_PA_BITS_48
1504	default 52 if ARM64_PA_BITS_52
1505
1506config ARM64_LPA2
1507	def_bool y
1508	depends on ARM64_PA_BITS_52 && !ARM64_64K_PAGES
1509
1510choice
1511	prompt "Endianness"
1512	default CPU_LITTLE_ENDIAN
1513	help
1514	  Select the endianness of data accesses performed by the CPU. Userspace
1515	  applications will need to be compiled and linked for the endianness
1516	  that is selected here.
1517
1518config CPU_BIG_ENDIAN
1519	bool "Build big-endian kernel"
1520	depends on BROKEN
1521	help
1522	  Say Y if you plan on running a kernel with a big-endian userspace.
1523
1524config CPU_LITTLE_ENDIAN
1525	bool "Build little-endian kernel"
1526	help
1527	  Say Y if you plan on running a kernel with a little-endian userspace.
1528	  This is usually the case for distributions targeting arm64.
1529
1530endchoice
1531
1532config NR_CPUS
1533	int "Maximum number of CPUs (2-4096)"
1534	range 2 4096
1535	default "512"
1536
1537config HOTPLUG_CPU
1538	bool "Support for hot-pluggable CPUs"
1539	select GENERIC_IRQ_MIGRATION
1540	help
1541	  Say Y here to experiment with turning CPUs off and on.  CPUs
1542	  can be controlled through /sys/devices/system/cpu.
1543
1544# Common NUMA Features
1545config NUMA
1546	bool "NUMA Memory Allocation and Scheduler Support"
1547	select GENERIC_ARCH_NUMA
1548	select OF_NUMA
1549	select HAVE_SETUP_PER_CPU_AREA
1550	select NEED_PER_CPU_EMBED_FIRST_CHUNK
1551	select NEED_PER_CPU_PAGE_FIRST_CHUNK
1552	select USE_PERCPU_NUMA_NODE_ID
1553	help
1554	  Enable NUMA (Non-Uniform Memory Access) support.
1555
1556	  The kernel will try to allocate memory used by a CPU on the
1557	  local memory of the CPU and add some more
1558	  NUMA awareness to the kernel.
1559
1560config NODES_SHIFT
1561	int "Maximum NUMA Nodes (as a power of 2)"
1562	range 1 10
1563	default "4"
1564	depends on NUMA
1565	help
1566	  Specify the maximum number of NUMA Nodes available on the target
1567	  system.  Increases memory reserved to accommodate various tables.
1568
1569source "kernel/Kconfig.hz"
1570
1571config ARCH_SPARSEMEM_ENABLE
1572	def_bool y
1573	select SPARSEMEM_VMEMMAP_ENABLE
1574
1575config HW_PERF_EVENTS
1576	def_bool y
1577	depends on ARM_PMU
1578
1579# Supported by clang >= 7.0 or GCC >= 12.0.0
1580config CC_HAVE_SHADOW_CALL_STACK
1581	def_bool $(cc-option, -fsanitize=shadow-call-stack -ffixed-x18)
1582
1583config PARAVIRT
1584	bool "Enable paravirtualization code"
1585	select HAVE_PV_STEAL_CLOCK_GEN
1586	help
1587	  This changes the kernel so it can modify itself when it is run
1588	  under a hypervisor, potentially improving performance significantly
1589	  over full virtualization.
1590
1591config PARAVIRT_TIME_ACCOUNTING
1592	bool "Paravirtual steal time accounting"
1593	select PARAVIRT
1594	help
1595	  Select this option to enable fine granularity task steal time
1596	  accounting. Time spent executing other tasks in parallel with
1597	  the current vCPU is discounted from the vCPU power. To account for
1598	  that, there can be a small performance impact.
1599
1600	  If in doubt, say N here.
1601
1602config ARCH_SUPPORTS_KEXEC
1603	def_bool PM_SLEEP_SMP
1604
1605config ARCH_SUPPORTS_KEXEC_FILE
1606	def_bool y
1607
1608config ARCH_SELECTS_KEXEC_FILE
1609	def_bool y
1610	depends on KEXEC_FILE
1611	select HAVE_IMA_KEXEC if IMA
1612
1613config ARCH_SUPPORTS_KEXEC_SIG
1614	def_bool y
1615
1616config ARCH_SUPPORTS_KEXEC_IMAGE_VERIFY_SIG
1617	def_bool y
1618
1619config ARCH_DEFAULT_KEXEC_IMAGE_VERIFY_SIG
1620	def_bool y
1621
1622config ARCH_SUPPORTS_KEXEC_HANDOVER
1623	def_bool y
1624
1625config ARCH_SUPPORTS_CRASH_DUMP
1626	def_bool y
1627
1628config ARCH_DEFAULT_CRASH_DUMP
1629	def_bool y
1630
1631config ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION
1632	def_bool CRASH_RESERVE
1633
1634config TRANS_TABLE
1635	def_bool y
1636	depends on HIBERNATION || KEXEC_CORE
1637
1638config XEN_DOM0
1639	def_bool y
1640	depends on XEN
1641
1642config XEN
1643	bool "Xen guest support on ARM64"
1644	depends on ARM64 && OF
1645	select SWIOTLB_XEN
1646	select PARAVIRT
1647	help
1648	  Say Y if you want to run Linux in a Virtual Machine on Xen on ARM64.
1649
1650# include/linux/mmzone.h requires the following to be true:
1651#
1652#   MAX_PAGE_ORDER + PAGE_SHIFT <= SECTION_SIZE_BITS
1653#
1654# so the maximum value of MAX_PAGE_ORDER is SECTION_SIZE_BITS - PAGE_SHIFT:
1655#
1656#     | SECTION_SIZE_BITS |  PAGE_SHIFT  |  max MAX_PAGE_ORDER  |  default MAX_PAGE_ORDER |
1657# ----+-------------------+--------------+----------------------+-------------------------+
1658# 4K  |       27          |      12      |       15             |         10              |
1659# 16K |       27          |      14      |       13             |         11              |
1660# 64K |       29          |      16      |       13             |         13              |
1661config ARCH_FORCE_MAX_ORDER
1662	int
1663	default "13" if ARM64_64K_PAGES
1664	default "11" if ARM64_16K_PAGES
1665	default "10"
1666	help
1667	  The kernel page allocator limits the size of maximal physically
1668	  contiguous allocations. The limit is called MAX_PAGE_ORDER and it
1669	  defines the maximal power of two of number of pages that can be
1670	  allocated as a single contiguous block. This option allows
1671	  overriding the default setting when ability to allocate very
1672	  large blocks of physically contiguous memory is required.
1673
1674	  The maximal size of allocation cannot exceed the size of the
1675	  section, so the value of MAX_PAGE_ORDER should satisfy
1676
1677	    MAX_PAGE_ORDER + PAGE_SHIFT <= SECTION_SIZE_BITS
1678
1679	  Don't change if unsure.
1680
1681config UNMAP_KERNEL_AT_EL0
1682	bool "Unmap kernel when running in userspace (KPTI)" if EXPERT
1683	default y
1684	help
1685	  Speculation attacks against some high-performance processors can
1686	  be used to bypass MMU permission checks and leak kernel data to
1687	  userspace. This can be defended against by unmapping the kernel
1688	  when running in userspace, mapping it back in on exception entry
1689	  via a trampoline page in the vector table.
1690
1691	  If unsure, say Y.
1692
1693config MITIGATE_SPECTRE_BRANCH_HISTORY
1694	bool "Mitigate Spectre style attacks against branch history" if EXPERT
1695	default y
1696	help
1697	  Speculation attacks against some high-performance processors can
1698	  make use of branch history to influence future speculation.
1699	  When taking an exception from user-space, a sequence of branches
1700	  or a firmware call overwrites the branch history.
1701
1702config ARM64_SW_TTBR0_PAN
1703	bool "Emulate Privileged Access Never using TTBR0_EL1 switching"
1704	depends on !KCSAN
1705	help
1706	  Enabling this option prevents the kernel from accessing
1707	  user-space memory directly by pointing TTBR0_EL1 to a reserved
1708	  zeroed area and reserved ASID. The user access routines
1709	  restore the valid TTBR0_EL1 temporarily.
1710
1711config ARM64_TAGGED_ADDR_ABI
1712	bool "Enable the tagged user addresses syscall ABI"
1713	default y
1714	help
1715	  When this option is enabled, user applications can opt in to a
1716	  relaxed ABI via prctl() allowing tagged addresses to be passed
1717	  to system calls as pointer arguments. For details, see
1718	  Documentation/arch/arm64/tagged-address-abi.rst.
1719
1720menuconfig COMPAT
1721	bool "Kernel support for 32-bit EL0"
1722	depends on ARM64_4K_PAGES || EXPERT
1723	select HAVE_UID16
1724	select OLD_SIGSUSPEND3
1725	select COMPAT_OLD_SIGACTION
1726	help
1727	  This option enables support for a 32-bit EL0 running under a 64-bit
1728	  kernel at EL1. AArch32-specific components such as system calls,
1729	  the user helper functions, VFP support and the ptrace interface are
1730	  handled appropriately by the kernel.
1731
1732	  If you use a page size other than 4KB (i.e, 16KB or 64KB), please be aware
1733	  that you will only be able to execute AArch32 binaries that were compiled
1734	  with page size aligned segments.
1735
1736	  If you want to execute 32-bit userspace applications, say Y.
1737
1738if COMPAT
1739
1740config KUSER_HELPERS
1741	bool "Enable kuser helpers page for 32-bit applications"
1742	default y
1743	help
1744	  Warning: disabling this option may break 32-bit user programs.
1745
1746	  Provide kuser helpers to compat tasks. The kernel provides
1747	  helper code to userspace in read only form at a fixed location
1748	  to allow userspace to be independent of the CPU type fitted to
1749	  the system. This permits binaries to be run on ARMv4 through
1750	  to ARMv8 without modification.
1751
1752	  See Documentation/arch/arm/kernel_user_helpers.rst for details.
1753
1754	  However, the fixed address nature of these helpers can be used
1755	  by ROP (return orientated programming) authors when creating
1756	  exploits.
1757
1758	  If all of the binaries and libraries which run on your platform
1759	  are built specifically for your platform, and make no use of
1760	  these helpers, then you can turn this option off to hinder
1761	  such exploits. However, in that case, if a binary or library
1762	  relying on those helpers is run, it will not function correctly.
1763
1764	  Say N here only if you are absolutely certain that you do not
1765	  need these helpers; otherwise, the safe option is to say Y.
1766
1767config COMPAT_VDSO
1768	bool "Enable vDSO for 32-bit applications"
1769	depends on !CPU_BIG_ENDIAN
1770	depends on (CC_IS_CLANG && LD_IS_LLD) || "$(CROSS_COMPILE_COMPAT)" != ""
1771	default y
1772	help
1773	  Place in the process address space of 32-bit applications an
1774	  ELF shared object providing fast implementations of gettimeofday
1775	  and clock_gettime.
1776
1777	  You must have a 32-bit build of glibc 2.22 or later for programs
1778	  to seamlessly take advantage of this.
1779
1780config THUMB2_COMPAT_VDSO
1781	bool "Compile the 32-bit vDSO for Thumb-2 mode" if EXPERT
1782	depends on COMPAT_VDSO
1783	default y
1784	help
1785	  Compile the compat vDSO with '-mthumb -fomit-frame-pointer' if y,
1786	  otherwise with '-marm'.
1787
1788config COMPAT_ALIGNMENT_FIXUPS
1789	bool "Fix up misaligned multi-word loads and stores in user space"
1790
1791menuconfig ARMV8_DEPRECATED
1792	bool "Emulate deprecated/obsolete ARMv8 instructions"
1793	depends on SYSCTL
1794	help
1795	  Legacy software support may require certain instructions
1796	  that have been deprecated or obsoleted in the architecture.
1797
1798	  Enable this config to enable selective emulation of these
1799	  features.
1800
1801	  If unsure, say Y
1802
1803if ARMV8_DEPRECATED
1804
1805config SWP_EMULATION
1806	bool "Emulate SWP/SWPB instructions"
1807	help
1808	  ARMv8 obsoletes the use of A32 SWP/SWPB instructions such that
1809	  they are always undefined. Say Y here to enable software
1810	  emulation of these instructions for userspace using LDXR/STXR.
1811	  This feature can be controlled at runtime with the abi.swp
1812	  sysctl which is disabled by default.
1813
1814	  In some older versions of glibc [<=2.8] SWP is used during futex
1815	  trylock() operations with the assumption that the code will not
1816	  be preempted. This invalid assumption may be more likely to fail
1817	  with SWP emulation enabled, leading to deadlock of the user
1818	  application.
1819
1820	  NOTE: when accessing uncached shared regions, LDXR/STXR rely
1821	  on an external transaction monitoring block called a global
1822	  monitor to maintain update atomicity. If your system does not
1823	  implement a global monitor, this option can cause programs that
1824	  perform SWP operations to uncached memory to deadlock.
1825
1826	  If unsure, say Y
1827
1828config CP15_BARRIER_EMULATION
1829	bool "Emulate CP15 Barrier instructions"
1830	help
1831	  The CP15 barrier instructions - CP15ISB, CP15DSB, and
1832	  CP15DMB - are deprecated in ARMv8 (and ARMv7). It is
1833	  strongly recommended to use the ISB, DSB, and DMB
1834	  instructions instead.
1835
1836	  Say Y here to enable software emulation of these
1837	  instructions for AArch32 userspace code. When this option is
1838	  enabled, CP15 barrier usage is traced which can help
1839	  identify software that needs updating. This feature can be
1840	  controlled at runtime with the abi.cp15_barrier sysctl.
1841
1842	  If unsure, say Y
1843
1844config SETEND_EMULATION
1845	bool "Emulate SETEND instruction"
1846	help
1847	  The SETEND instruction alters the data-endianness of the
1848	  AArch32 EL0, and is deprecated in ARMv8.
1849
1850	  Say Y here to enable software emulation of the instruction
1851	  for AArch32 userspace code. This feature can be controlled
1852	  at runtime with the abi.setend sysctl.
1853
1854	  Note: All the cpus on the system must have mixed endian support at EL0
1855	  for this feature to be enabled. If a new CPU - which doesn't support mixed
1856	  endian - is hotplugged in after this feature has been enabled, there could
1857	  be unexpected results in the applications.
1858
1859	  If unsure, say Y
1860endif # ARMV8_DEPRECATED
1861
1862endif # COMPAT
1863
1864menu "ARMv8.1 architectural features"
1865
1866config ARM64_HW_AFDBM
1867	bool "Support for hardware updates of the Access and Dirty page flags"
1868	default y
1869	help
1870	  The ARMv8.1 architecture extensions introduce support for
1871	  hardware updates of the access and dirty information in page
1872	  table entries. When enabled in TCR_EL1 (HA and HD bits) on
1873	  capable processors, accesses to pages with PTE_AF cleared will
1874	  set this bit instead of raising an access flag fault.
1875	  Similarly, writes to read-only pages with the DBM bit set will
1876	  clear the read-only bit (AP[2]) instead of raising a
1877	  permission fault.
1878
1879	  Kernels built with this configuration option enabled continue
1880	  to work on pre-ARMv8.1 hardware and the performance impact is
1881	  minimal. If unsure, say Y.
1882
1883endmenu # "ARMv8.1 architectural features"
1884
1885menu "ARMv8.2 architectural features"
1886
1887config ARM64_PMEM
1888	bool "Enable support for persistent memory"
1889	select ARCH_HAS_PMEM_API
1890	select ARCH_HAS_UACCESS_FLUSHCACHE
1891	help
1892	  Say Y to enable support for the persistent memory API based on the
1893	  ARMv8.2 DCPoP feature.
1894
1895	  The feature is detected at runtime, and the kernel will use DC CVAC
1896	  operations if DC CVAP is not supported (following the behaviour of
1897	  DC CVAP itself if the system does not define a point of persistence).
1898
1899config ARM64_RAS_EXTN
1900	bool "Enable support for RAS CPU Extensions"
1901	default y
1902	help
1903	  CPUs that support the Reliability, Availability and Serviceability
1904	  (RAS) Extensions, part of ARMv8.2 are able to track faults and
1905	  errors, classify them and report them to software.
1906
1907	  On CPUs with these extensions system software can use additional
1908	  barriers to determine if faults are pending and read the
1909	  classification from a new set of registers.
1910
1911	  Selecting this feature will allow the kernel to use these barriers
1912	  and access the new registers if the system supports the extension.
1913	  Platform RAS features may additionally depend on firmware support.
1914
1915config ARM64_CNP
1916	bool "Enable support for Common Not Private (CNP) translations"
1917	default y
1918	help
1919	  Common Not Private (CNP) allows translation table entries to
1920	  be shared between different PEs in the same inner shareable
1921	  domain, so the hardware can use this fact to optimise the
1922	  caching of such entries in the TLB.
1923
1924	  Selecting this option allows the CNP feature to be detected
1925	  at runtime, and does not affect PEs that do not implement
1926	  this feature.
1927
1928endmenu # "ARMv8.2 architectural features"
1929
1930menu "ARMv8.3 architectural features"
1931
1932config ARM64_PTR_AUTH
1933	bool "Enable support for pointer authentication"
1934	default y
1935	help
1936	  Pointer authentication (part of the ARMv8.3 Extensions) provides
1937	  instructions for signing and authenticating pointers against secret
1938	  keys, which can be used to mitigate Return Oriented Programming (ROP)
1939	  and other attacks.
1940
1941	  This option enables these instructions at EL0 (i.e. for userspace).
1942	  Choosing this option will cause the kernel to initialise secret keys
1943	  for each process at exec() time, with these keys being
1944	  context-switched along with the process.
1945
1946	  The feature is detected at runtime. If the feature is not present in
1947	  hardware it will not be advertised to userspace/KVM guest nor will it
1948	  be enabled.
1949
1950	  If the feature is present on the boot CPU but not on a late CPU, then
1951	  the late CPU will be parked. Also, if the boot CPU does not have
1952	  address auth and the late CPU has then the late CPU will still boot
1953	  but with the feature disabled. On such a system, this option should
1954	  not be selected.
1955
1956config ARM64_PTR_AUTH_KERNEL
1957	bool "Use pointer authentication for kernel"
1958	default y
1959	depends on ARM64_PTR_AUTH
1960	# Modern compilers insert a .note.gnu.property section note for PAC
1961	# which is only understood by binutils starting with version 2.33.1.
1962	depends on LD_IS_LLD || LD_VERSION >= 23301 || (CC_IS_GCC && GCC_VERSION < 90100)
1963	depends on !CC_IS_CLANG || AS_HAS_CFI_NEGATE_RA_STATE
1964	depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_ARGS)
1965	help
1966	  If the compiler supports the -mbranch-protection or
1967	  -msign-return-address flag (e.g. GCC 7 or later), then this option
1968	  will cause the kernel itself to be compiled with return address
1969	  protection. In this case, and if the target hardware is known to
1970	  support pointer authentication, then CONFIG_STACKPROTECTOR can be
1971	  disabled with minimal loss of protection.
1972
1973	  This feature works with FUNCTION_GRAPH_TRACER option only if
1974	  DYNAMIC_FTRACE_WITH_ARGS is enabled.
1975
1976config CC_HAS_BRANCH_PROT_PAC_RET
1977	# GCC 9 or later, clang 8 or later
1978	def_bool $(cc-option,-mbranch-protection=pac-ret+leaf)
1979
1980config AS_HAS_CFI_NEGATE_RA_STATE
1981	# binutils 2.34+
1982	def_bool $(as-instr,.cfi_startproc\n.cfi_negate_ra_state\n.cfi_endproc\n)
1983
1984endmenu # "ARMv8.3 architectural features"
1985
1986menu "ARMv8.4 architectural features"
1987
1988config ARM64_AMU_EXTN
1989	bool "Enable support for the Activity Monitors Unit CPU extension"
1990	default y
1991	help
1992	  The activity monitors extension is an optional extension introduced
1993	  by the ARMv8.4 CPU architecture. This enables support for version 1
1994	  of the activity monitors architecture, AMUv1.
1995
1996	  To enable the use of this extension on CPUs that implement it, say Y.
1997
1998	  Note that for architectural reasons, firmware _must_ implement AMU
1999	  support when running on CPUs that present the activity monitors
2000	  extension. The required support is present in:
2001	    * Version 1.5 and later of the ARM Trusted Firmware
2002
2003	  For kernels that have this configuration enabled but boot with broken
2004	  firmware, you may need to say N here until the firmware is fixed.
2005	  Otherwise you may experience firmware panics or lockups when
2006	  accessing the counter registers. Even if you are not observing these
2007	  symptoms, the values returned by the register reads might not
2008	  correctly reflect reality. Most commonly, the value read will be 0,
2009	  indicating that the counter is not enabled.
2010
2011config ARM64_TLB_RANGE
2012	bool "Enable support for tlbi range feature"
2013	default y
2014	help
2015	  ARMv8.4-TLBI provides TLBI invalidation instruction that apply to a
2016	  range of input addresses.
2017
2018config ARM64_MPAM
2019	bool "Enable support for MPAM"
2020	select ARM64_MPAM_DRIVER if EXPERT	# does nothing yet
2021	select ACPI_MPAM if ACPI
2022	help
2023	  Memory System Resource Partitioning and Monitoring (MPAM) is an
2024	  optional extension to the Arm architecture that allows each
2025	  transaction issued to the memory system to be labelled with a
2026	  Partition identifier (PARTID) and Performance Monitoring Group
2027	  identifier (PMG).
2028
2029	  Memory system components, such as the caches, can be configured with
2030	  policies to control how much of various physical resources (such as
2031	  memory bandwidth or cache memory) the transactions labelled with each
2032	  PARTID can consume.  Depending on the capabilities of the hardware,
2033	  the PARTID and PMG can also be used as filtering criteria to measure
2034	  the memory system resource consumption of different parts of a
2035	  workload.
2036
2037	  Use of this extension requires CPU support, support in the
2038	  Memory System Components (MSC), and a description from firmware
2039	  of where the MSCs are in the address space.
2040
2041	  MPAM is exposed to user-space via the resctrl pseudo filesystem.
2042
2043endmenu # "ARMv8.4 architectural features"
2044
2045menu "ARMv8.5 architectural features"
2046
2047config AS_HAS_ARMV8_5
2048	def_bool $(cc-option,-Wa$(comma)-march=armv8.5-a)
2049
2050config ARM64_BTI
2051	bool "Branch Target Identification support"
2052	default y
2053	help
2054	  Branch Target Identification (part of the ARMv8.5 Extensions)
2055	  provides a mechanism to limit the set of locations to which computed
2056	  branch instructions such as BR or BLR can jump.
2057
2058	  To make use of BTI on CPUs that support it, say Y.
2059
2060	  BTI is intended to provide complementary protection to other control
2061	  flow integrity protection mechanisms, such as the Pointer
2062	  authentication mechanism provided as part of the ARMv8.3 Extensions.
2063	  For this reason, it does not make sense to enable this option without
2064	  also enabling support for pointer authentication.  Thus, when
2065	  enabling this option you should also select ARM64_PTR_AUTH=y.
2066
2067	  Userspace binaries must also be specifically compiled to make use of
2068	  this mechanism.  If you say N here or the hardware does not support
2069	  BTI, such binaries can still run, but you get no additional
2070	  enforcement of branch destinations.
2071
2072config ARM64_BTI_KERNEL
2073	bool "Use Branch Target Identification for kernel"
2074	default y
2075	depends on ARM64_BTI
2076	depends on ARM64_PTR_AUTH_KERNEL
2077	depends on CC_HAS_BRANCH_PROT_PAC_RET_BTI
2078	# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94697
2079	depends on !CC_IS_GCC || GCC_VERSION >= 100100
2080	# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106671
2081	depends on !CC_IS_GCC
2082	depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_ARGS)
2083	help
2084	  Build the kernel with Branch Target Identification annotations
2085	  and enable enforcement of this for kernel code. When this option
2086	  is enabled and the system supports BTI all kernel code including
2087	  modular code must have BTI enabled.
2088
2089config CC_HAS_BRANCH_PROT_PAC_RET_BTI
2090	# GCC 9 or later, clang 8 or later
2091	def_bool $(cc-option,-mbranch-protection=pac-ret+leaf+bti)
2092
2093config ARM64_E0PD
2094	bool "Enable support for E0PD"
2095	default y
2096	help
2097	  E0PD (part of the ARMv8.5 extensions) allows us to ensure
2098	  that EL0 accesses made via TTBR1 always fault in constant time,
2099	  providing similar benefits to KASLR as those provided by KPTI, but
2100	  with lower overhead and without disrupting legitimate access to
2101	  kernel memory such as SPE.
2102
2103	  This option enables E0PD for TTBR1 where available.
2104
2105config ARM64_AS_HAS_MTE
2106	# Initial support for MTE went in binutils 2.32.0, checked with
2107	# ".arch armv8.5-a+memtag" below. However, this was incomplete
2108	# as a late addition to the final architecture spec (LDGM/STGM)
2109	# is only supported in the newer 2.32.x and 2.33 binutils
2110	# versions, hence the extra "stgm" instruction check below.
2111	def_bool $(as-instr,.arch armv8.5-a+memtag\nstgm xzr$(comma)[x0])
2112
2113config ARM64_MTE
2114	bool "Memory Tagging Extension support"
2115	default y
2116	depends on ARM64_AS_HAS_MTE && ARM64_TAGGED_ADDR_ABI
2117	depends on AS_HAS_ARMV8_5
2118	# Required for tag checking in the uaccess routines
2119	select ARCH_HAS_SUBPAGE_FAULTS
2120	select ARCH_USES_HIGH_VMA_FLAGS
2121	select ARCH_USES_PG_ARCH_2
2122	select ARCH_USES_PG_ARCH_3
2123	help
2124	  Memory Tagging (part of the ARMv8.5 Extensions) provides
2125	  architectural support for run-time, always-on detection of
2126	  various classes of memory error to aid with software debugging
2127	  to eliminate vulnerabilities arising from memory-unsafe
2128	  languages.
2129
2130	  This option enables the support for the Memory Tagging
2131	  Extension at EL0 (i.e. for userspace).
2132
2133	  Selecting this option allows the feature to be detected at
2134	  runtime. Any secondary CPU not implementing this feature will
2135	  not be allowed a late bring-up.
2136
2137	  Userspace binaries that want to use this feature must
2138	  explicitly opt in. The mechanism for the userspace is
2139	  described in:
2140
2141	  Documentation/arch/arm64/memory-tagging-extension.rst.
2142
2143endmenu # "ARMv8.5 architectural features"
2144
2145menu "ARMv8.7 architectural features"
2146
2147config ARM64_EPAN
2148	bool "Enable support for Enhanced Privileged Access Never (EPAN)"
2149	default y
2150	help
2151	  Enhanced Privileged Access Never (EPAN) allows Privileged
2152	  Access Never to be used with Execute-only mappings.
2153
2154	  The feature is detected at runtime, and will remain disabled
2155	  if the cpu does not implement the feature.
2156endmenu # "ARMv8.7 architectural features"
2157
2158config AS_HAS_MOPS
2159	def_bool $(as-instr,.arch_extension mops)
2160
2161menu "ARMv8.9 architectural features"
2162
2163config ARM64_POE
2164	prompt "Permission Overlay Extension"
2165	def_bool y
2166	select ARCH_USES_HIGH_VMA_FLAGS
2167	select ARCH_HAS_PKEYS
2168	help
2169	  The Permission Overlay Extension is used to implement Memory
2170	  Protection Keys. Memory Protection Keys provides a mechanism for
2171	  enforcing page-based protections, but without requiring modification
2172	  of the page tables when an application changes protection domains.
2173
2174	  For details, see Documentation/core-api/protection-keys.rst
2175
2176	  If unsure, say y.
2177
2178config ARCH_PKEY_BITS
2179	int
2180	default 3
2181
2182config ARM64_HAFT
2183	bool "Support for Hardware managed Access Flag for Table Descriptors"
2184	depends on ARM64_HW_AFDBM
2185	default y
2186	help
2187	  The ARMv8.9/ARMv9.5 introduces the feature Hardware managed Access
2188	  Flag for Table descriptors. When enabled an architectural executed
2189	  memory access will update the Access Flag in each Table descriptor
2190	  which is accessed during the translation table walk and for which
2191	  the Access Flag is 0. The Access Flag of the Table descriptor use
2192	  the same bit of PTE_AF.
2193
2194	  The feature will only be enabled if all the CPUs in the system
2195	  support this feature. If unsure, say Y.
2196
2197endmenu # "ARMv8.9 architectural features"
2198
2199menu "ARMv9.4 architectural features"
2200
2201config ARM64_GCS
2202	bool "Enable support for Guarded Control Stack (GCS)"
2203	default y
2204	select ARCH_HAS_USER_SHADOW_STACK
2205	select ARCH_USES_HIGH_VMA_FLAGS
2206	help
2207	  Guarded Control Stack (GCS) provides support for a separate
2208	  stack with restricted access which contains only return
2209	  addresses.  This can be used to harden against some attacks
2210	  by comparing return address used by the program with what is
2211	  stored in the GCS, and may also be used to efficiently obtain
2212	  the call stack for applications such as profiling.
2213
2214	  The feature is detected at runtime, and will remain disabled
2215	  if the system does not implement the feature.
2216
2217endmenu # "ARMv9.4 architectural features"
2218
2219config ARM64_SVE
2220	bool "ARM Scalable Vector Extension support"
2221	default y
2222	help
2223	  The Scalable Vector Extension (SVE) is an extension to the AArch64
2224	  execution state which complements and extends the SIMD functionality
2225	  of the base architecture to support much larger vectors and to enable
2226	  additional vectorisation opportunities.
2227
2228	  To enable use of this extension on CPUs that implement it, say Y.
2229
2230	  On CPUs that support the SVE2 extensions, this option will enable
2231	  those too.
2232
2233	  Note that for architectural reasons, firmware _must_ implement SVE
2234	  support when running on SVE capable hardware.  The required support
2235	  is present in:
2236
2237	    * version 1.5 and later of the ARM Trusted Firmware
2238	    * the AArch64 boot wrapper since commit 5e1261e08abf
2239	      ("bootwrapper: SVE: Enable SVE for EL2 and below").
2240
2241	  For other firmware implementations, consult the firmware documentation
2242	  or vendor.
2243
2244	  If you need the kernel to boot on SVE-capable hardware with broken
2245	  firmware, you may need to say N here until you get your firmware
2246	  fixed.  Otherwise, you may experience firmware panics or lockups when
2247	  booting the kernel.  If unsure and you are not observing these
2248	  symptoms, you should assume that it is safe to say Y.
2249
2250config ARM64_SME
2251	bool "ARM Scalable Matrix Extension support"
2252	default y
2253	depends on ARM64_SVE
2254	help
2255	  The Scalable Matrix Extension (SME) is an extension to the AArch64
2256	  execution state which utilises a substantial subset of the SVE
2257	  instruction set, together with the addition of new architectural
2258	  register state capable of holding two dimensional matrix tiles to
2259	  enable various matrix operations.
2260
2261config ARM64_PSEUDO_NMI
2262	bool "Support for NMI-like interrupts"
2263	select ARM_GIC_V3
2264	help
2265	  Adds support for mimicking Non-Maskable Interrupts through the use of
2266	  GIC interrupt priority. This support requires version 3 or later of
2267	  ARM GIC.
2268
2269	  This high priority configuration for interrupts needs to be
2270	  explicitly enabled by setting the kernel parameter
2271	  "irqchip.gicv3_pseudo_nmi" to 1.
2272
2273	  If unsure, say N
2274
2275if ARM64_PSEUDO_NMI
2276config ARM64_DEBUG_PRIORITY_MASKING
2277	bool "Debug interrupt priority masking"
2278	help
2279	  This adds runtime checks to functions enabling/disabling
2280	  interrupts when using priority masking. The additional checks verify
2281	  the validity of ICC_PMR_EL1 when calling concerned functions.
2282
2283	  If unsure, say N
2284endif # ARM64_PSEUDO_NMI
2285
2286config RELOCATABLE
2287	bool "Build a relocatable kernel image" if EXPERT
2288	select ARCH_HAS_RELR
2289	default y
2290	help
2291	  This builds the kernel as a Position Independent Executable (PIE),
2292	  which retains all relocation metadata required to relocate the
2293	  kernel binary at runtime to a different virtual address than the
2294	  address it was linked at.
2295	  Since AArch64 uses the RELA relocation format, this requires a
2296	  relocation pass at runtime even if the kernel is loaded at the
2297	  same address it was linked at.
2298
2299config RANDOMIZE_BASE
2300	bool "Randomize the address of the kernel image"
2301	select RELOCATABLE
2302	help
2303	  Randomizes the virtual address at which the kernel image is
2304	  loaded, as a security feature that deters exploit attempts
2305	  relying on knowledge of the location of kernel internals.
2306
2307	  It is the bootloader's job to provide entropy, by passing a
2308	  random u64 value in /chosen/kaslr-seed at kernel entry.
2309
2310	  When booting via the UEFI stub, it will invoke the firmware's
2311	  EFI_RNG_PROTOCOL implementation (if available) to supply entropy
2312	  to the kernel proper. In addition, it will randomise the physical
2313	  location of the kernel Image as well.
2314
2315	  If unsure, say N.
2316
2317config RANDOMIZE_MODULE_REGION_FULL
2318	bool "Randomize the module region over a 2 GB range"
2319	depends on RANDOMIZE_BASE
2320	default y
2321	help
2322	  Randomizes the location of the module region inside a 2 GB window
2323	  covering the core kernel. This way, it is less likely for modules
2324	  to leak information about the location of core kernel data structures
2325	  but it does imply that function calls between modules and the core
2326	  kernel will need to be resolved via veneers in the module PLT.
2327
2328	  When this option is not set, the module region will be randomized over
2329	  a limited range that contains the [_stext, _etext] interval of the
2330	  core kernel, so branch relocations are almost always in range unless
2331	  the region is exhausted. In this particular case of region
2332	  exhaustion, modules might be able to fall back to a larger 2GB area.
2333
2334config CC_HAVE_STACKPROTECTOR_SYSREG
2335	def_bool $(cc-option,-mstack-protector-guard=sysreg -mstack-protector-guard-reg=sp_el0 -mstack-protector-guard-offset=0)
2336
2337config STACKPROTECTOR_PER_TASK
2338	def_bool y
2339	depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_SYSREG
2340
2341config UNWIND_PATCH_PAC_INTO_SCS
2342	bool "Enable shadow call stack dynamically using code patching"
2343	depends on CC_IS_CLANG
2344	depends on ARM64_PTR_AUTH_KERNEL && CC_HAS_BRANCH_PROT_PAC_RET
2345	depends on SHADOW_CALL_STACK
2346	select UNWIND_TABLES
2347	select DYNAMIC_SCS
2348
2349config ARM64_CONTPTE
2350	bool "Contiguous PTE mappings for user memory" if EXPERT
2351	depends on TRANSPARENT_HUGEPAGE
2352	default y
2353	help
2354	  When enabled, user mappings are configured using the PTE contiguous
2355	  bit, for any mappings that meet the size and alignment requirements.
2356	  This reduces TLB pressure and improves performance.
2357
2358endmenu # "Kernel Features"
2359
2360menu "Boot options"
2361
2362config ARM64_ACPI_PARKING_PROTOCOL
2363	bool "Enable support for the ARM64 ACPI parking protocol"
2364	depends on ACPI
2365	help
2366	  Enable support for the ARM64 ACPI parking protocol. If disabled
2367	  the kernel will not allow booting through the ARM64 ACPI parking
2368	  protocol even if the corresponding data is present in the ACPI
2369	  MADT table.
2370
2371config CMDLINE
2372	string "Default kernel command string"
2373	default ""
2374	help
2375	  Provide a set of default command-line options at build time by
2376	  entering them here. As a minimum, you should specify the the
2377	  root device (e.g. root=/dev/nfs).
2378
2379choice
2380	prompt "Kernel command line type"
2381	depends on CMDLINE != ""
2382	default CMDLINE_FROM_BOOTLOADER
2383	help
2384	  Choose how the kernel will handle the provided default kernel
2385	  command line string.
2386
2387config CMDLINE_FROM_BOOTLOADER
2388	bool "Use bootloader kernel arguments if available"
2389	help
2390	  Uses the command-line options passed by the boot loader. If
2391	  the boot loader doesn't provide any, the default kernel command
2392	  string provided in CMDLINE will be used.
2393
2394config CMDLINE_FORCE
2395	bool "Always use the default kernel command string"
2396	help
2397	  Always use the default kernel command string, even if the boot
2398	  loader passes other arguments to the kernel.
2399	  This is useful if you cannot or don't want to change the
2400	  command-line options your boot loader passes to the kernel.
2401
2402endchoice
2403
2404config EFI_STUB
2405	bool
2406
2407config EFI
2408	bool "UEFI runtime support"
2409	depends on OF && !CPU_BIG_ENDIAN
2410	depends on KERNEL_MODE_NEON
2411	select ARCH_SUPPORTS_ACPI
2412	select LIBFDT
2413	select UCS2_STRING
2414	select EFI_PARAMS_FROM_FDT
2415	select EFI_RUNTIME_WRAPPERS
2416	select EFI_STUB
2417	select EFI_GENERIC_STUB
2418	imply IMA_SECURE_AND_OR_TRUSTED_BOOT
2419	default y
2420	help
2421	  This option provides support for runtime services provided
2422	  by UEFI firmware (such as non-volatile variables, realtime
2423	  clock, and platform reset). A UEFI stub is also provided to
2424	  allow the kernel to be booted as an EFI application. This
2425	  is only useful on systems that have UEFI firmware.
2426
2427config COMPRESSED_INSTALL
2428	bool "Install compressed image by default"
2429	help
2430	  This makes the regular "make install" install the compressed
2431	  image we built, not the legacy uncompressed one.
2432
2433	  You can check that a compressed image works for you by doing
2434	  "make zinstall" first, and verifying that everything is fine
2435	  in your environment before making "make install" do this for
2436	  you.
2437
2438config DMI
2439	bool "Enable support for SMBIOS (DMI) tables"
2440	depends on EFI
2441	default y
2442	help
2443	  This enables SMBIOS/DMI feature for systems.
2444
2445	  This option is only useful on systems that have UEFI firmware.
2446	  However, even with this option, the resultant kernel should
2447	  continue to boot on existing non-UEFI platforms.
2448
2449endmenu # "Boot options"
2450
2451menu "Power management options"
2452
2453source "kernel/power/Kconfig"
2454
2455config ARCH_HIBERNATION_POSSIBLE
2456	def_bool y
2457	depends on CPU_PM
2458
2459config ARCH_HIBERNATION_HEADER
2460	def_bool y
2461	depends on HIBERNATION
2462
2463config ARCH_SUSPEND_POSSIBLE
2464	def_bool y
2465
2466endmenu # "Power management options"
2467
2468menu "CPU Power Management"
2469
2470source "drivers/cpuidle/Kconfig"
2471
2472source "drivers/cpufreq/Kconfig"
2473
2474endmenu # "CPU Power Management"
2475
2476source "drivers/acpi/Kconfig"
2477
2478source "arch/arm64/kvm/Kconfig"
2479
2480source "kernel/livepatch/Kconfig"
2481