xref: /linux/arch/arm64/Kconfig (revision 00c010e130e58301db2ea0cec1eadc931e1cb8cf)
1# SPDX-License-Identifier: GPL-2.0-only
2config ARM64
3	def_bool y
4	select ACPI_APMT if ACPI
5	select ACPI_CCA_REQUIRED if ACPI
6	select ACPI_GENERIC_GSI if ACPI
7	select ACPI_GTDT if ACPI
8	select ACPI_HOTPLUG_CPU if ACPI_PROCESSOR && HOTPLUG_CPU
9	select ACPI_IORT if ACPI
10	select ACPI_REDUCED_HARDWARE_ONLY if ACPI
11	select ACPI_MCFG if (ACPI && PCI)
12	select ACPI_SPCR_TABLE if ACPI
13	select ACPI_PPTT if ACPI
14	select ARCH_HAS_DEBUG_WX
15	select ARCH_BINFMT_ELF_EXTRA_PHDRS
16	select ARCH_BINFMT_ELF_STATE
17	select ARCH_ENABLE_HUGEPAGE_MIGRATION if HUGETLB_PAGE && MIGRATION
18	select ARCH_ENABLE_MEMORY_HOTPLUG
19	select ARCH_ENABLE_MEMORY_HOTREMOVE
20	select ARCH_ENABLE_SPLIT_PMD_PTLOCK if PGTABLE_LEVELS > 2
21	select ARCH_ENABLE_THP_MIGRATION if TRANSPARENT_HUGEPAGE
22	select ARCH_HAS_CACHE_LINE_SIZE
23	select ARCH_HAS_CC_PLATFORM
24	select ARCH_HAS_CRC32
25	select ARCH_HAS_CRC_T10DIF if KERNEL_MODE_NEON
26	select ARCH_HAS_CURRENT_STACK_POINTER
27	select ARCH_HAS_DEBUG_VIRTUAL
28	select ARCH_HAS_DEBUG_VM_PGTABLE
29	select ARCH_HAS_DMA_OPS if XEN
30	select ARCH_HAS_DMA_PREP_COHERENT
31	select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI
32	select ARCH_HAS_FAST_MULTIPLIER
33	select ARCH_HAS_FORTIFY_SOURCE
34	select ARCH_HAS_GCOV_PROFILE_ALL
35	select ARCH_HAS_GIGANTIC_PAGE
36	select ARCH_HAS_KCOV
37	select ARCH_HAS_KERNEL_FPU_SUPPORT if KERNEL_MODE_NEON
38	select ARCH_HAS_KEEPINITRD
39	select ARCH_HAS_MEMBARRIER_SYNC_CORE
40	select ARCH_HAS_MEM_ENCRYPT
41	select ARCH_SUPPORTS_MSEAL_SYSTEM_MAPPINGS
42	select ARCH_HAS_NMI_SAFE_THIS_CPU_OPS
43	select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
44	select ARCH_HAS_NONLEAF_PMD_YOUNG if ARM64_HAFT
45	select ARCH_HAS_PREEMPT_LAZY
46	select ARCH_HAS_PTDUMP
47	select ARCH_HAS_PTE_DEVMAP
48	select ARCH_HAS_PTE_SPECIAL
49	select ARCH_HAS_HW_PTE_YOUNG
50	select ARCH_HAS_SETUP_DMA_OPS
51	select ARCH_HAS_SET_DIRECT_MAP
52	select ARCH_HAS_SET_MEMORY
53	select ARCH_HAS_MEM_ENCRYPT
54	select ARCH_HAS_FORCE_DMA_UNENCRYPTED
55	select ARCH_STACKWALK
56	select ARCH_HAS_STRICT_KERNEL_RWX
57	select ARCH_HAS_STRICT_MODULE_RWX
58	select ARCH_HAS_SYNC_DMA_FOR_DEVICE
59	select ARCH_HAS_SYNC_DMA_FOR_CPU
60	select ARCH_HAS_SYSCALL_WRAPPER
61	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
62	select ARCH_HAS_ZONE_DMA_SET if EXPERT
63	select ARCH_HAVE_ELF_PROT
64	select ARCH_HAVE_NMI_SAFE_CMPXCHG
65	select ARCH_HAVE_TRACE_MMIO_ACCESS
66	select ARCH_INLINE_READ_LOCK if !PREEMPTION
67	select ARCH_INLINE_READ_LOCK_BH if !PREEMPTION
68	select ARCH_INLINE_READ_LOCK_IRQ if !PREEMPTION
69	select ARCH_INLINE_READ_LOCK_IRQSAVE if !PREEMPTION
70	select ARCH_INLINE_READ_UNLOCK if !PREEMPTION
71	select ARCH_INLINE_READ_UNLOCK_BH if !PREEMPTION
72	select ARCH_INLINE_READ_UNLOCK_IRQ if !PREEMPTION
73	select ARCH_INLINE_READ_UNLOCK_IRQRESTORE if !PREEMPTION
74	select ARCH_INLINE_WRITE_LOCK if !PREEMPTION
75	select ARCH_INLINE_WRITE_LOCK_BH if !PREEMPTION
76	select ARCH_INLINE_WRITE_LOCK_IRQ if !PREEMPTION
77	select ARCH_INLINE_WRITE_LOCK_IRQSAVE if !PREEMPTION
78	select ARCH_INLINE_WRITE_UNLOCK if !PREEMPTION
79	select ARCH_INLINE_WRITE_UNLOCK_BH if !PREEMPTION
80	select ARCH_INLINE_WRITE_UNLOCK_IRQ if !PREEMPTION
81	select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE if !PREEMPTION
82	select ARCH_INLINE_SPIN_TRYLOCK if !PREEMPTION
83	select ARCH_INLINE_SPIN_TRYLOCK_BH if !PREEMPTION
84	select ARCH_INLINE_SPIN_LOCK if !PREEMPTION
85	select ARCH_INLINE_SPIN_LOCK_BH if !PREEMPTION
86	select ARCH_INLINE_SPIN_LOCK_IRQ if !PREEMPTION
87	select ARCH_INLINE_SPIN_LOCK_IRQSAVE if !PREEMPTION
88	select ARCH_INLINE_SPIN_UNLOCK if !PREEMPTION
89	select ARCH_INLINE_SPIN_UNLOCK_BH if !PREEMPTION
90	select ARCH_INLINE_SPIN_UNLOCK_IRQ if !PREEMPTION
91	select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE if !PREEMPTION
92	select ARCH_KEEP_MEMBLOCK
93	select ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE
94	select ARCH_USE_CMPXCHG_LOCKREF
95	select ARCH_USE_GNU_PROPERTY
96	select ARCH_USE_MEMTEST
97	select ARCH_USE_QUEUED_RWLOCKS
98	select ARCH_USE_QUEUED_SPINLOCKS
99	select ARCH_USE_SYM_ANNOTATIONS
100	select ARCH_SUPPORTS_DEBUG_PAGEALLOC
101	select ARCH_SUPPORTS_HUGETLBFS
102	select ARCH_SUPPORTS_MEMORY_FAILURE
103	select ARCH_SUPPORTS_SHADOW_CALL_STACK if CC_HAVE_SHADOW_CALL_STACK
104	select ARCH_SUPPORTS_LTO_CLANG if CPU_LITTLE_ENDIAN
105	select ARCH_SUPPORTS_LTO_CLANG_THIN
106	select ARCH_SUPPORTS_CFI_CLANG
107	select ARCH_SUPPORTS_ATOMIC_RMW
108	select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
109	select ARCH_SUPPORTS_NUMA_BALANCING
110	select ARCH_SUPPORTS_PAGE_TABLE_CHECK
111	select ARCH_SUPPORTS_PER_VMA_LOCK
112	select ARCH_SUPPORTS_HUGE_PFNMAP if TRANSPARENT_HUGEPAGE
113	select ARCH_SUPPORTS_RT
114	select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
115	select ARCH_WANT_COMPAT_IPC_PARSE_VERSION if COMPAT
116	select ARCH_WANT_DEFAULT_BPF_JIT
117	select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT
118	select ARCH_WANT_FRAME_POINTERS
119	select ARCH_WANT_HUGE_PMD_SHARE if ARM64_4K_PAGES || (ARM64_16K_PAGES && !ARM64_VA_BITS_36)
120	select ARCH_WANT_LD_ORPHAN_WARN
121	select ARCH_WANTS_EXECMEM_LATE
122	select ARCH_WANTS_NO_INSTR
123	select ARCH_WANTS_THP_SWAP if ARM64_4K_PAGES
124	select ARCH_HAS_UBSAN
125	select ARM_AMBA
126	select ARM_ARCH_TIMER
127	select ARM_GIC
128	select AUDIT_ARCH_COMPAT_GENERIC
129	select ARM_GIC_V2M if PCI
130	select ARM_GIC_V3
131	select ARM_GIC_V3_ITS if PCI
132	select ARM_PSCI_FW
133	select BUILDTIME_TABLE_SORT
134	select CLONE_BACKWARDS
135	select COMMON_CLK
136	select CPU_PM if (SUSPEND || CPU_IDLE)
137	select CPUMASK_OFFSTACK if NR_CPUS > 256
138	select DCACHE_WORD_ACCESS
139	select DYNAMIC_FTRACE if FUNCTION_TRACER
140	select DMA_BOUNCE_UNALIGNED_KMALLOC
141	select DMA_DIRECT_REMAP
142	select EDAC_SUPPORT
143	select FRAME_POINTER
144	select FUNCTION_ALIGNMENT_4B
145	select FUNCTION_ALIGNMENT_8B if DYNAMIC_FTRACE_WITH_CALL_OPS
146	select GENERIC_ALLOCATOR
147	select GENERIC_ARCH_TOPOLOGY
148	select GENERIC_CLOCKEVENTS_BROADCAST
149	select GENERIC_CPU_AUTOPROBE
150	select GENERIC_CPU_DEVICES
151	select GENERIC_CPU_VULNERABILITIES
152	select GENERIC_EARLY_IOREMAP
153	select GENERIC_IDLE_POLL_SETUP
154	select GENERIC_IOREMAP
155	select GENERIC_IRQ_IPI
156	select GENERIC_IRQ_KEXEC_CLEAR_VM_FORWARD
157	select GENERIC_IRQ_PROBE
158	select GENERIC_IRQ_SHOW
159	select GENERIC_IRQ_SHOW_LEVEL
160	select GENERIC_LIB_DEVMEM_IS_ALLOWED
161	select GENERIC_PCI_IOMAP
162	select GENERIC_SCHED_CLOCK
163	select GENERIC_SMP_IDLE_THREAD
164	select GENERIC_TIME_VSYSCALL
165	select GENERIC_GETTIMEOFDAY
166	select GENERIC_VDSO_DATA_STORE
167	select GENERIC_VDSO_TIME_NS
168	select HARDIRQS_SW_RESEND
169	select HAS_IOPORT
170	select HAVE_MOVE_PMD
171	select HAVE_MOVE_PUD
172	select HAVE_PCI
173	select HAVE_ACPI_APEI if (ACPI && EFI)
174	select HAVE_ALIGNED_STRUCT_PAGE
175	select HAVE_ARCH_AUDITSYSCALL
176	select HAVE_ARCH_BITREVERSE
177	select HAVE_ARCH_COMPILER_H
178	select HAVE_ARCH_HUGE_VMALLOC
179	select HAVE_ARCH_HUGE_VMAP
180	select HAVE_ARCH_JUMP_LABEL
181	select HAVE_ARCH_JUMP_LABEL_RELATIVE
182	select HAVE_ARCH_KASAN
183	select HAVE_ARCH_KASAN_VMALLOC
184	select HAVE_ARCH_KASAN_SW_TAGS
185	select HAVE_ARCH_KASAN_HW_TAGS if ARM64_MTE
186	# Some instrumentation may be unsound, hence EXPERT
187	select HAVE_ARCH_KCSAN if EXPERT
188	select HAVE_ARCH_KFENCE
189	select HAVE_ARCH_KGDB
190	select HAVE_ARCH_MMAP_RND_BITS
191	select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT
192	select HAVE_ARCH_PREL32_RELOCATIONS
193	select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET
194	select HAVE_ARCH_SECCOMP_FILTER
195	select HAVE_ARCH_STACKLEAK
196	select HAVE_ARCH_THREAD_STRUCT_WHITELIST
197	select HAVE_ARCH_TRACEHOOK
198	select HAVE_ARCH_TRANSPARENT_HUGEPAGE
199	select HAVE_ARCH_VMAP_STACK
200	select HAVE_ARM_SMCCC
201	select HAVE_ASM_MODVERSIONS
202	select HAVE_EBPF_JIT
203	select HAVE_C_RECORDMCOUNT
204	select HAVE_CMPXCHG_DOUBLE
205	select HAVE_CMPXCHG_LOCAL
206	select HAVE_CONTEXT_TRACKING_USER
207	select HAVE_DEBUG_KMEMLEAK
208	select HAVE_DMA_CONTIGUOUS
209	select HAVE_DYNAMIC_FTRACE
210	select HAVE_DYNAMIC_FTRACE_WITH_ARGS \
211		if (GCC_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS || \
212		    CLANG_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS)
213	select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS \
214		if DYNAMIC_FTRACE_WITH_ARGS && DYNAMIC_FTRACE_WITH_CALL_OPS
215	select HAVE_DYNAMIC_FTRACE_WITH_CALL_OPS \
216		if (DYNAMIC_FTRACE_WITH_ARGS && !CFI_CLANG && \
217		    (CC_IS_CLANG || !CC_OPTIMIZE_FOR_SIZE))
218	select FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY \
219		if DYNAMIC_FTRACE_WITH_ARGS
220	select HAVE_SAMPLE_FTRACE_DIRECT
221	select HAVE_SAMPLE_FTRACE_DIRECT_MULTI
222	select HAVE_BUILDTIME_MCOUNT_SORT
223	select HAVE_EFFICIENT_UNALIGNED_ACCESS
224	select HAVE_GUP_FAST
225	select HAVE_FTRACE_GRAPH_FUNC
226	select HAVE_FTRACE_MCOUNT_RECORD
227	select HAVE_FUNCTION_TRACER
228	select HAVE_FUNCTION_ERROR_INJECTION
229	select HAVE_FUNCTION_GRAPH_FREGS
230	select HAVE_FUNCTION_GRAPH_TRACER
231	select HAVE_GCC_PLUGINS
232	select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && \
233		HW_PERF_EVENTS && HAVE_PERF_EVENTS_NMI
234	select HAVE_HW_BREAKPOINT if PERF_EVENTS
235	select HAVE_IOREMAP_PROT
236	select HAVE_IRQ_TIME_ACCOUNTING
237	select HAVE_MOD_ARCH_SPECIFIC
238	select HAVE_NMI
239	select HAVE_PERF_EVENTS
240	select HAVE_PERF_EVENTS_NMI if ARM64_PSEUDO_NMI
241	select HAVE_PERF_REGS
242	select HAVE_PERF_USER_STACK_DUMP
243	select HAVE_PREEMPT_DYNAMIC_KEY
244	select HAVE_REGS_AND_STACK_ACCESS_API
245	select HAVE_POSIX_CPU_TIMERS_TASK_WORK
246	select HAVE_FUNCTION_ARG_ACCESS_API
247	select MMU_GATHER_RCU_TABLE_FREE
248	select HAVE_RSEQ
249	select HAVE_RUST if RUSTC_SUPPORTS_ARM64
250	select HAVE_STACKPROTECTOR
251	select HAVE_SYSCALL_TRACEPOINTS
252	select HAVE_KPROBES
253	select HAVE_KRETPROBES
254	select HAVE_GENERIC_VDSO
255	select HOTPLUG_CORE_SYNC_DEAD if HOTPLUG_CPU
256	select HOTPLUG_SMT if HOTPLUG_CPU
257	select IRQ_DOMAIN
258	select IRQ_FORCED_THREADING
259	select KASAN_VMALLOC if KASAN
260	select LOCK_MM_AND_FIND_VMA
261	select MODULES_USE_ELF_RELA
262	select NEED_DMA_MAP_STATE
263	select NEED_SG_DMA_LENGTH
264	select OF
265	select OF_EARLY_FLATTREE
266	select PCI_DOMAINS_GENERIC if PCI
267	select PCI_ECAM if (ACPI && PCI)
268	select PCI_SYSCALL if PCI
269	select POWER_RESET
270	select POWER_SUPPLY
271	select SPARSE_IRQ
272	select SWIOTLB
273	select SYSCTL_EXCEPTION_TRACE
274	select THREAD_INFO_IN_TASK
275	select HAVE_ARCH_USERFAULTFD_MINOR if USERFAULTFD
276	select HAVE_ARCH_USERFAULTFD_WP if USERFAULTFD
277	select TRACE_IRQFLAGS_SUPPORT
278	select TRACE_IRQFLAGS_NMI_SUPPORT
279	select HAVE_SOFTIRQ_ON_OWN_STACK
280	select USER_STACKTRACE_SUPPORT
281	select VDSO_GETRANDOM
282	help
283	  ARM 64-bit (AArch64) Linux support.
284
285config RUSTC_SUPPORTS_ARM64
286	def_bool y
287	depends on CPU_LITTLE_ENDIAN
288	# Shadow call stack is only supported on certain rustc versions.
289	#
290	# When using the UNWIND_PATCH_PAC_INTO_SCS option, rustc version 1.80+ is
291	# required due to use of the -Zfixed-x18 flag.
292	#
293	# Otherwise, rustc version 1.82+ is required due to use of the
294	# -Zsanitizer=shadow-call-stack flag.
295	depends on !SHADOW_CALL_STACK || RUSTC_VERSION >= 108200 || RUSTC_VERSION >= 108000 && UNWIND_PATCH_PAC_INTO_SCS
296
297config CLANG_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS
298	def_bool CC_IS_CLANG
299	# https://github.com/ClangBuiltLinux/linux/issues/1507
300	depends on AS_IS_GNU || (AS_IS_LLVM && (LD_IS_LLD || LD_VERSION >= 23600))
301
302config GCC_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS
303	def_bool CC_IS_GCC
304	depends on $(cc-option,-fpatchable-function-entry=2)
305
306config 64BIT
307	def_bool y
308
309config MMU
310	def_bool y
311
312config ARM64_CONT_PTE_SHIFT
313	int
314	default 5 if PAGE_SIZE_64KB
315	default 7 if PAGE_SIZE_16KB
316	default 4
317
318config ARM64_CONT_PMD_SHIFT
319	int
320	default 5 if PAGE_SIZE_64KB
321	default 5 if PAGE_SIZE_16KB
322	default 4
323
324config ARCH_MMAP_RND_BITS_MIN
325	default 14 if PAGE_SIZE_64KB
326	default 16 if PAGE_SIZE_16KB
327	default 18
328
329# max bits determined by the following formula:
330#  VA_BITS - PTDESC_TABLE_SHIFT
331config ARCH_MMAP_RND_BITS_MAX
332	default 19 if ARM64_VA_BITS=36
333	default 24 if ARM64_VA_BITS=39
334	default 27 if ARM64_VA_BITS=42
335	default 30 if ARM64_VA_BITS=47
336	default 29 if (ARM64_VA_BITS=48 || ARM64_VA_BITS=52) && ARM64_64K_PAGES
337	default 31 if (ARM64_VA_BITS=48 || ARM64_VA_BITS=52) && ARM64_16K_PAGES
338	default 33 if (ARM64_VA_BITS=48 || ARM64_VA_BITS=52)
339	default 14 if ARM64_64K_PAGES
340	default 16 if ARM64_16K_PAGES
341	default 18
342
343config ARCH_MMAP_RND_COMPAT_BITS_MIN
344	default 7 if ARM64_64K_PAGES
345	default 9 if ARM64_16K_PAGES
346	default 11
347
348config ARCH_MMAP_RND_COMPAT_BITS_MAX
349	default 16
350
351config NO_IOPORT_MAP
352	def_bool y if !PCI
353
354config STACKTRACE_SUPPORT
355	def_bool y
356
357config ILLEGAL_POINTER_VALUE
358	hex
359	default 0xdead000000000000
360
361config LOCKDEP_SUPPORT
362	def_bool y
363
364config GENERIC_BUG
365	def_bool y
366	depends on BUG
367
368config GENERIC_BUG_RELATIVE_POINTERS
369	def_bool y
370	depends on GENERIC_BUG
371
372config GENERIC_HWEIGHT
373	def_bool y
374
375config GENERIC_CSUM
376	def_bool y
377
378config GENERIC_CALIBRATE_DELAY
379	def_bool y
380
381config SMP
382	def_bool y
383
384config KERNEL_MODE_NEON
385	def_bool y
386
387config FIX_EARLYCON_MEM
388	def_bool y
389
390config PGTABLE_LEVELS
391	int
392	default 2 if ARM64_16K_PAGES && ARM64_VA_BITS_36
393	default 2 if ARM64_64K_PAGES && ARM64_VA_BITS_42
394	default 3 if ARM64_64K_PAGES && (ARM64_VA_BITS_48 || ARM64_VA_BITS_52)
395	default 3 if ARM64_4K_PAGES && ARM64_VA_BITS_39
396	default 3 if ARM64_16K_PAGES && ARM64_VA_BITS_47
397	default 4 if ARM64_16K_PAGES && (ARM64_VA_BITS_48 || ARM64_VA_BITS_52)
398	default 4 if !ARM64_64K_PAGES && ARM64_VA_BITS_48
399	default 5 if ARM64_4K_PAGES && ARM64_VA_BITS_52
400
401config ARCH_SUPPORTS_UPROBES
402	def_bool y
403
404config ARCH_PROC_KCORE_TEXT
405	def_bool y
406
407config BROKEN_GAS_INST
408	def_bool !$(as-instr,1:\n.inst 0\n.rept . - 1b\n\nnop\n.endr\n)
409
410config BUILTIN_RETURN_ADDRESS_STRIPS_PAC
411	bool
412	# Clang's __builtin_return_address() strips the PAC since 12.0.0
413	# https://github.com/llvm/llvm-project/commit/2a96f47c5ffca84cd774ad402cacd137f4bf45e2
414	default y if CC_IS_CLANG
415	# GCC's __builtin_return_address() strips the PAC since 11.1.0,
416	# and this was backported to 10.2.0, 9.4.0, 8.5.0, but not earlier
417	# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94891
418	default y if CC_IS_GCC && (GCC_VERSION >= 110100)
419	default y if CC_IS_GCC && (GCC_VERSION >= 100200) && (GCC_VERSION < 110000)
420	default y if CC_IS_GCC && (GCC_VERSION >=  90400) && (GCC_VERSION < 100000)
421	default y if CC_IS_GCC && (GCC_VERSION >=  80500) && (GCC_VERSION <  90000)
422	default n
423
424config KASAN_SHADOW_OFFSET
425	hex
426	depends on KASAN_GENERIC || KASAN_SW_TAGS
427	default 0xdfff800000000000 if (ARM64_VA_BITS_48 || (ARM64_VA_BITS_52 && !ARM64_16K_PAGES)) && !KASAN_SW_TAGS
428	default 0xdfffc00000000000 if (ARM64_VA_BITS_47 || ARM64_VA_BITS_52) && ARM64_16K_PAGES && !KASAN_SW_TAGS
429	default 0xdffffe0000000000 if ARM64_VA_BITS_42 && !KASAN_SW_TAGS
430	default 0xdfffffc000000000 if ARM64_VA_BITS_39 && !KASAN_SW_TAGS
431	default 0xdffffff800000000 if ARM64_VA_BITS_36 && !KASAN_SW_TAGS
432	default 0xefff800000000000 if (ARM64_VA_BITS_48 || (ARM64_VA_BITS_52 && !ARM64_16K_PAGES)) && KASAN_SW_TAGS
433	default 0xefffc00000000000 if (ARM64_VA_BITS_47 || ARM64_VA_BITS_52) && ARM64_16K_PAGES && KASAN_SW_TAGS
434	default 0xeffffe0000000000 if ARM64_VA_BITS_42 && KASAN_SW_TAGS
435	default 0xefffffc000000000 if ARM64_VA_BITS_39 && KASAN_SW_TAGS
436	default 0xeffffff800000000 if ARM64_VA_BITS_36 && KASAN_SW_TAGS
437	default 0xffffffffffffffff
438
439config UNWIND_TABLES
440	bool
441
442source "arch/arm64/Kconfig.platforms"
443
444menu "Kernel Features"
445
446menu "ARM errata workarounds via the alternatives framework"
447
448config AMPERE_ERRATUM_AC03_CPU_38
449        bool "AmpereOne: AC03_CPU_38: Certain bits in the Virtualization Translation Control Register and Translation Control Registers do not follow RES0 semantics"
450	default y
451	help
452	  This option adds an alternative code sequence to work around Ampere
453	  errata AC03_CPU_38 and AC04_CPU_10 on AmpereOne.
454
455	  The affected design reports FEAT_HAFDBS as not implemented in
456	  ID_AA64MMFR1_EL1.HAFDBS, but (V)TCR_ELx.{HA,HD} are not RES0
457	  as required by the architecture. The unadvertised HAFDBS
458	  implementation suffers from an additional erratum where hardware
459	  A/D updates can occur after a PTE has been marked invalid.
460
461	  The workaround forces KVM to explicitly set VTCR_EL2.HA to 0,
462	  which avoids enabling unadvertised hardware Access Flag management
463	  at stage-2.
464
465	  If unsure, say Y.
466
467config AMPERE_ERRATUM_AC04_CPU_23
468        bool "AmpereOne: AC04_CPU_23:  Failure to synchronize writes to HCR_EL2 may corrupt address translations."
469	default y
470	help
471	  This option adds an alternative code sequence to work around Ampere
472	  errata AC04_CPU_23 on AmpereOne.
473
474	  Updates to HCR_EL2 can rarely corrupt simultaneous translations for
475	  data addresses initiated by load/store instructions. Only
476	  instruction initiated translations are vulnerable, not translations
477	  from prefetches for example. A DSB before the store to HCR_EL2 is
478	  sufficient to prevent older instructions from hitting the window
479	  for corruption, and an ISB after is sufficient to prevent younger
480	  instructions from hitting the window for corruption.
481
482	  If unsure, say Y.
483
484config ARM64_WORKAROUND_CLEAN_CACHE
485	bool
486
487config ARM64_ERRATUM_826319
488	bool "Cortex-A53: 826319: System might deadlock if a write cannot complete until read data is accepted"
489	default y
490	select ARM64_WORKAROUND_CLEAN_CACHE
491	help
492	  This option adds an alternative code sequence to work around ARM
493	  erratum 826319 on Cortex-A53 parts up to r0p2 with an AMBA 4 ACE or
494	  AXI master interface and an L2 cache.
495
496	  If a Cortex-A53 uses an AMBA AXI4 ACE interface to other processors
497	  and is unable to accept a certain write via this interface, it will
498	  not progress on read data presented on the read data channel and the
499	  system can deadlock.
500
501	  The workaround promotes data cache clean instructions to
502	  data cache clean-and-invalidate.
503	  Please note that this does not necessarily enable the workaround,
504	  as it depends on the alternative framework, which will only patch
505	  the kernel if an affected CPU is detected.
506
507	  If unsure, say Y.
508
509config ARM64_ERRATUM_827319
510	bool "Cortex-A53: 827319: Data cache clean instructions might cause overlapping transactions to the interconnect"
511	default y
512	select ARM64_WORKAROUND_CLEAN_CACHE
513	help
514	  This option adds an alternative code sequence to work around ARM
515	  erratum 827319 on Cortex-A53 parts up to r0p2 with an AMBA 5 CHI
516	  master interface and an L2 cache.
517
518	  Under certain conditions this erratum can cause a clean line eviction
519	  to occur at the same time as another transaction to the same address
520	  on the AMBA 5 CHI interface, which can cause data corruption if the
521	  interconnect reorders the two transactions.
522
523	  The workaround promotes data cache clean instructions to
524	  data cache clean-and-invalidate.
525	  Please note that this does not necessarily enable the workaround,
526	  as it depends on the alternative framework, which will only patch
527	  the kernel if an affected CPU is detected.
528
529	  If unsure, say Y.
530
531config ARM64_ERRATUM_824069
532	bool "Cortex-A53: 824069: Cache line might not be marked as clean after a CleanShared snoop"
533	default y
534	select ARM64_WORKAROUND_CLEAN_CACHE
535	help
536	  This option adds an alternative code sequence to work around ARM
537	  erratum 824069 on Cortex-A53 parts up to r0p2 when it is connected
538	  to a coherent interconnect.
539
540	  If a Cortex-A53 processor is executing a store or prefetch for
541	  write instruction at the same time as a processor in another
542	  cluster is executing a cache maintenance operation to the same
543	  address, then this erratum might cause a clean cache line to be
544	  incorrectly marked as dirty.
545
546	  The workaround promotes data cache clean instructions to
547	  data cache clean-and-invalidate.
548	  Please note that this option does not necessarily enable the
549	  workaround, as it depends on the alternative framework, which will
550	  only patch the kernel if an affected CPU is detected.
551
552	  If unsure, say Y.
553
554config ARM64_ERRATUM_819472
555	bool "Cortex-A53: 819472: Store exclusive instructions might cause data corruption"
556	default y
557	select ARM64_WORKAROUND_CLEAN_CACHE
558	help
559	  This option adds an alternative code sequence to work around ARM
560	  erratum 819472 on Cortex-A53 parts up to r0p1 with an L2 cache
561	  present when it is connected to a coherent interconnect.
562
563	  If the processor is executing a load and store exclusive sequence at
564	  the same time as a processor in another cluster is executing a cache
565	  maintenance operation to the same address, then this erratum might
566	  cause data corruption.
567
568	  The workaround promotes data cache clean instructions to
569	  data cache clean-and-invalidate.
570	  Please note that this does not necessarily enable the workaround,
571	  as it depends on the alternative framework, which will only patch
572	  the kernel if an affected CPU is detected.
573
574	  If unsure, say Y.
575
576config ARM64_ERRATUM_832075
577	bool "Cortex-A57: 832075: possible deadlock on mixing exclusive memory accesses with device loads"
578	default y
579	help
580	  This option adds an alternative code sequence to work around ARM
581	  erratum 832075 on Cortex-A57 parts up to r1p2.
582
583	  Affected Cortex-A57 parts might deadlock when exclusive load/store
584	  instructions to Write-Back memory are mixed with Device loads.
585
586	  The workaround is to promote device loads to use Load-Acquire
587	  semantics.
588	  Please note that this does not necessarily enable the workaround,
589	  as it depends on the alternative framework, which will only patch
590	  the kernel if an affected CPU is detected.
591
592	  If unsure, say Y.
593
594config ARM64_ERRATUM_834220
595	bool "Cortex-A57: 834220: Stage 2 translation fault might be incorrectly reported in presence of a Stage 1 fault (rare)"
596	depends on KVM
597	help
598	  This option adds an alternative code sequence to work around ARM
599	  erratum 834220 on Cortex-A57 parts up to r1p2.
600
601	  Affected Cortex-A57 parts might report a Stage 2 translation
602	  fault as the result of a Stage 1 fault for load crossing a
603	  page boundary when there is a permission or device memory
604	  alignment fault at Stage 1 and a translation fault at Stage 2.
605
606	  The workaround is to verify that the Stage 1 translation
607	  doesn't generate a fault before handling the Stage 2 fault.
608	  Please note that this does not necessarily enable the workaround,
609	  as it depends on the alternative framework, which will only patch
610	  the kernel if an affected CPU is detected.
611
612	  If unsure, say N.
613
614config ARM64_ERRATUM_1742098
615	bool "Cortex-A57/A72: 1742098: ELR recorded incorrectly on interrupt taken between cryptographic instructions in a sequence"
616	depends on COMPAT
617	default y
618	help
619	  This option removes the AES hwcap for aarch32 user-space to
620	  workaround erratum 1742098 on Cortex-A57 and Cortex-A72.
621
622	  Affected parts may corrupt the AES state if an interrupt is
623	  taken between a pair of AES instructions. These instructions
624	  are only present if the cryptography extensions are present.
625	  All software should have a fallback implementation for CPUs
626	  that don't implement the cryptography extensions.
627
628	  If unsure, say Y.
629
630config ARM64_ERRATUM_845719
631	bool "Cortex-A53: 845719: a load might read incorrect data"
632	depends on COMPAT
633	default y
634	help
635	  This option adds an alternative code sequence to work around ARM
636	  erratum 845719 on Cortex-A53 parts up to r0p4.
637
638	  When running a compat (AArch32) userspace on an affected Cortex-A53
639	  part, a load at EL0 from a virtual address that matches the bottom 32
640	  bits of the virtual address used by a recent load at (AArch64) EL1
641	  might return incorrect data.
642
643	  The workaround is to write the contextidr_el1 register on exception
644	  return to a 32-bit task.
645	  Please note that this does not necessarily enable the workaround,
646	  as it depends on the alternative framework, which will only patch
647	  the kernel if an affected CPU is detected.
648
649	  If unsure, say Y.
650
651config ARM64_ERRATUM_843419
652	bool "Cortex-A53: 843419: A load or store might access an incorrect address"
653	default y
654	help
655	  This option links the kernel with '--fix-cortex-a53-843419' and
656	  enables PLT support to replace certain ADRP instructions, which can
657	  cause subsequent memory accesses to use an incorrect address on
658	  Cortex-A53 parts up to r0p4.
659
660	  If unsure, say Y.
661
662config ARM64_ERRATUM_1024718
663	bool "Cortex-A55: 1024718: Update of DBM/AP bits without break before make might result in incorrect update"
664	default y
665	help
666	  This option adds a workaround for ARM Cortex-A55 Erratum 1024718.
667
668	  Affected Cortex-A55 cores (all revisions) could cause incorrect
669	  update of the hardware dirty bit when the DBM/AP bits are updated
670	  without a break-before-make. The workaround is to disable the usage
671	  of hardware DBM locally on the affected cores. CPUs not affected by
672	  this erratum will continue to use the feature.
673
674	  If unsure, say Y.
675
676config ARM64_ERRATUM_1418040
677	bool "Cortex-A76/Neoverse-N1: MRC read following MRRC read of specific Generic Timer in AArch32 might give incorrect result"
678	default y
679	depends on COMPAT
680	help
681	  This option adds a workaround for ARM Cortex-A76/Neoverse-N1
682	  errata 1188873 and 1418040.
683
684	  Affected Cortex-A76/Neoverse-N1 cores (r0p0 to r3p1) could
685	  cause register corruption when accessing the timer registers
686	  from AArch32 userspace.
687
688	  If unsure, say Y.
689
690config ARM64_WORKAROUND_SPECULATIVE_AT
691	bool
692
693config ARM64_ERRATUM_1165522
694	bool "Cortex-A76: 1165522: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
695	default y
696	select ARM64_WORKAROUND_SPECULATIVE_AT
697	help
698	  This option adds a workaround for ARM Cortex-A76 erratum 1165522.
699
700	  Affected Cortex-A76 cores (r0p0, r1p0, r2p0) could end-up with
701	  corrupted TLBs by speculating an AT instruction during a guest
702	  context switch.
703
704	  If unsure, say Y.
705
706config ARM64_ERRATUM_1319367
707	bool "Cortex-A57/A72: 1319537: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
708	default y
709	select ARM64_WORKAROUND_SPECULATIVE_AT
710	help
711	  This option adds work arounds for ARM Cortex-A57 erratum 1319537
712	  and A72 erratum 1319367
713
714	  Cortex-A57 and A72 cores could end-up with corrupted TLBs by
715	  speculating an AT instruction during a guest context switch.
716
717	  If unsure, say Y.
718
719config ARM64_ERRATUM_1530923
720	bool "Cortex-A55: 1530923: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
721	default y
722	select ARM64_WORKAROUND_SPECULATIVE_AT
723	help
724	  This option adds a workaround for ARM Cortex-A55 erratum 1530923.
725
726	  Affected Cortex-A55 cores (r0p0, r0p1, r1p0, r2p0) could end-up with
727	  corrupted TLBs by speculating an AT instruction during a guest
728	  context switch.
729
730	  If unsure, say Y.
731
732config ARM64_WORKAROUND_REPEAT_TLBI
733	bool
734
735config ARM64_ERRATUM_2441007
736	bool "Cortex-A55: Completion of affected memory accesses might not be guaranteed by completion of a TLBI (rare)"
737	select ARM64_WORKAROUND_REPEAT_TLBI
738	help
739	  This option adds a workaround for ARM Cortex-A55 erratum #2441007.
740
741	  Under very rare circumstances, affected Cortex-A55 CPUs
742	  may not handle a race between a break-before-make sequence on one
743	  CPU, and another CPU accessing the same page. This could allow a
744	  store to a page that has been unmapped.
745
746	  Work around this by adding the affected CPUs to the list that needs
747	  TLB sequences to be done twice.
748
749	  If unsure, say N.
750
751config ARM64_ERRATUM_1286807
752	bool "Cortex-A76: Modification of the translation table for a virtual address might lead to read-after-read ordering violation (rare)"
753	select ARM64_WORKAROUND_REPEAT_TLBI
754	help
755	  This option adds a workaround for ARM Cortex-A76 erratum 1286807.
756
757	  On the affected Cortex-A76 cores (r0p0 to r3p0), if a virtual
758	  address for a cacheable mapping of a location is being
759	  accessed by a core while another core is remapping the virtual
760	  address to a new physical page using the recommended
761	  break-before-make sequence, then under very rare circumstances
762	  TLBI+DSB completes before a read using the translation being
763	  invalidated has been observed by other observers. The
764	  workaround repeats the TLBI+DSB operation.
765
766	  If unsure, say N.
767
768config ARM64_ERRATUM_1463225
769	bool "Cortex-A76: Software Step might prevent interrupt recognition"
770	default y
771	help
772	  This option adds a workaround for Arm Cortex-A76 erratum 1463225.
773
774	  On the affected Cortex-A76 cores (r0p0 to r3p1), software stepping
775	  of a system call instruction (SVC) can prevent recognition of
776	  subsequent interrupts when software stepping is disabled in the
777	  exception handler of the system call and either kernel debugging
778	  is enabled or VHE is in use.
779
780	  Work around the erratum by triggering a dummy step exception
781	  when handling a system call from a task that is being stepped
782	  in a VHE configuration of the kernel.
783
784	  If unsure, say Y.
785
786config ARM64_ERRATUM_1542419
787	bool "Neoverse-N1: workaround mis-ordering of instruction fetches (rare)"
788	help
789	  This option adds a workaround for ARM Neoverse-N1 erratum
790	  1542419.
791
792	  Affected Neoverse-N1 cores could execute a stale instruction when
793	  modified by another CPU. The workaround depends on a firmware
794	  counterpart.
795
796	  Workaround the issue by hiding the DIC feature from EL0. This
797	  forces user-space to perform cache maintenance.
798
799	  If unsure, say N.
800
801config ARM64_ERRATUM_1508412
802	bool "Cortex-A77: 1508412: workaround deadlock on sequence of NC/Device load and store exclusive or PAR read"
803	default y
804	help
805	  This option adds a workaround for Arm Cortex-A77 erratum 1508412.
806
807	  Affected Cortex-A77 cores (r0p0, r1p0) could deadlock on a sequence
808	  of a store-exclusive or read of PAR_EL1 and a load with device or
809	  non-cacheable memory attributes. The workaround depends on a firmware
810	  counterpart.
811
812	  KVM guests must also have the workaround implemented or they can
813	  deadlock the system.
814
815	  Work around the issue by inserting DMB SY barriers around PAR_EL1
816	  register reads and warning KVM users. The DMB barrier is sufficient
817	  to prevent a speculative PAR_EL1 read.
818
819	  If unsure, say Y.
820
821config ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
822	bool
823
824config ARM64_ERRATUM_2051678
825	bool "Cortex-A510: 2051678: disable Hardware Update of the page table dirty bit"
826	default y
827	help
828	  This options adds the workaround for ARM Cortex-A510 erratum ARM64_ERRATUM_2051678.
829	  Affected Cortex-A510 might not respect the ordering rules for
830	  hardware update of the page table's dirty bit. The workaround
831	  is to not enable the feature on affected CPUs.
832
833	  If unsure, say Y.
834
835config ARM64_ERRATUM_2077057
836	bool "Cortex-A510: 2077057: workaround software-step corrupting SPSR_EL2"
837	default y
838	help
839	  This option adds the workaround for ARM Cortex-A510 erratum 2077057.
840	  Affected Cortex-A510 may corrupt SPSR_EL2 when the a step exception is
841	  expected, but a Pointer Authentication trap is taken instead. The
842	  erratum causes SPSR_EL1 to be copied to SPSR_EL2, which could allow
843	  EL1 to cause a return to EL2 with a guest controlled ELR_EL2.
844
845	  This can only happen when EL2 is stepping EL1.
846
847	  When these conditions occur, the SPSR_EL2 value is unchanged from the
848	  previous guest entry, and can be restored from the in-memory copy.
849
850	  If unsure, say Y.
851
852config ARM64_ERRATUM_2658417
853	bool "Cortex-A510: 2658417: remove BF16 support due to incorrect result"
854	default y
855	help
856	  This option adds the workaround for ARM Cortex-A510 erratum 2658417.
857	  Affected Cortex-A510 (r0p0 to r1p1) may produce the wrong result for
858	  BFMMLA or VMMLA instructions in rare circumstances when a pair of
859	  A510 CPUs are using shared neon hardware. As the sharing is not
860	  discoverable by the kernel, hide the BF16 HWCAP to indicate that
861	  user-space should not be using these instructions.
862
863	  If unsure, say Y.
864
865config ARM64_ERRATUM_2119858
866	bool "Cortex-A710/X2: 2119858: workaround TRBE overwriting trace data in FILL mode"
867	default y
868	depends on CORESIGHT_TRBE
869	select ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
870	help
871	  This option adds the workaround for ARM Cortex-A710/X2 erratum 2119858.
872
873	  Affected Cortex-A710/X2 cores could overwrite up to 3 cache lines of trace
874	  data at the base of the buffer (pointed to by TRBASER_EL1) in FILL mode in
875	  the event of a WRAP event.
876
877	  Work around the issue by always making sure we move the TRBPTR_EL1 by
878	  256 bytes before enabling the buffer and filling the first 256 bytes of
879	  the buffer with ETM ignore packets upon disabling.
880
881	  If unsure, say Y.
882
883config ARM64_ERRATUM_2139208
884	bool "Neoverse-N2: 2139208: workaround TRBE overwriting trace data in FILL mode"
885	default y
886	depends on CORESIGHT_TRBE
887	select ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
888	help
889	  This option adds the workaround for ARM Neoverse-N2 erratum 2139208.
890
891	  Affected Neoverse-N2 cores could overwrite up to 3 cache lines of trace
892	  data at the base of the buffer (pointed to by TRBASER_EL1) in FILL mode in
893	  the event of a WRAP event.
894
895	  Work around the issue by always making sure we move the TRBPTR_EL1 by
896	  256 bytes before enabling the buffer and filling the first 256 bytes of
897	  the buffer with ETM ignore packets upon disabling.
898
899	  If unsure, say Y.
900
901config ARM64_WORKAROUND_TSB_FLUSH_FAILURE
902	bool
903
904config ARM64_ERRATUM_2054223
905	bool "Cortex-A710: 2054223: workaround TSB instruction failing to flush trace"
906	default y
907	select ARM64_WORKAROUND_TSB_FLUSH_FAILURE
908	help
909	  Enable workaround for ARM Cortex-A710 erratum 2054223
910
911	  Affected cores may fail to flush the trace data on a TSB instruction, when
912	  the PE is in trace prohibited state. This will cause losing a few bytes
913	  of the trace cached.
914
915	  Workaround is to issue two TSB consecutively on affected cores.
916
917	  If unsure, say Y.
918
919config ARM64_ERRATUM_2067961
920	bool "Neoverse-N2: 2067961: workaround TSB instruction failing to flush trace"
921	default y
922	select ARM64_WORKAROUND_TSB_FLUSH_FAILURE
923	help
924	  Enable workaround for ARM Neoverse-N2 erratum 2067961
925
926	  Affected cores may fail to flush the trace data on a TSB instruction, when
927	  the PE is in trace prohibited state. This will cause losing a few bytes
928	  of the trace cached.
929
930	  Workaround is to issue two TSB consecutively on affected cores.
931
932	  If unsure, say Y.
933
934config ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE
935	bool
936
937config ARM64_ERRATUM_2253138
938	bool "Neoverse-N2: 2253138: workaround TRBE writing to address out-of-range"
939	depends on CORESIGHT_TRBE
940	default y
941	select ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE
942	help
943	  This option adds the workaround for ARM Neoverse-N2 erratum 2253138.
944
945	  Affected Neoverse-N2 cores might write to an out-of-range address, not reserved
946	  for TRBE. Under some conditions, the TRBE might generate a write to the next
947	  virtually addressed page following the last page of the TRBE address space
948	  (i.e., the TRBLIMITR_EL1.LIMIT), instead of wrapping around to the base.
949
950	  Work around this in the driver by always making sure that there is a
951	  page beyond the TRBLIMITR_EL1.LIMIT, within the space allowed for the TRBE.
952
953	  If unsure, say Y.
954
955config ARM64_ERRATUM_2224489
956	bool "Cortex-A710/X2: 2224489: workaround TRBE writing to address out-of-range"
957	depends on CORESIGHT_TRBE
958	default y
959	select ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE
960	help
961	  This option adds the workaround for ARM Cortex-A710/X2 erratum 2224489.
962
963	  Affected Cortex-A710/X2 cores might write to an out-of-range address, not reserved
964	  for TRBE. Under some conditions, the TRBE might generate a write to the next
965	  virtually addressed page following the last page of the TRBE address space
966	  (i.e., the TRBLIMITR_EL1.LIMIT), instead of wrapping around to the base.
967
968	  Work around this in the driver by always making sure that there is a
969	  page beyond the TRBLIMITR_EL1.LIMIT, within the space allowed for the TRBE.
970
971	  If unsure, say Y.
972
973config ARM64_ERRATUM_2441009
974	bool "Cortex-A510: Completion of affected memory accesses might not be guaranteed by completion of a TLBI (rare)"
975	select ARM64_WORKAROUND_REPEAT_TLBI
976	help
977	  This option adds a workaround for ARM Cortex-A510 erratum #2441009.
978
979	  Under very rare circumstances, affected Cortex-A510 CPUs
980	  may not handle a race between a break-before-make sequence on one
981	  CPU, and another CPU accessing the same page. This could allow a
982	  store to a page that has been unmapped.
983
984	  Work around this by adding the affected CPUs to the list that needs
985	  TLB sequences to be done twice.
986
987	  If unsure, say N.
988
989config ARM64_ERRATUM_2064142
990	bool "Cortex-A510: 2064142: workaround TRBE register writes while disabled"
991	depends on CORESIGHT_TRBE
992	default y
993	help
994	  This option adds the workaround for ARM Cortex-A510 erratum 2064142.
995
996	  Affected Cortex-A510 core might fail to write into system registers after the
997	  TRBE has been disabled. Under some conditions after the TRBE has been disabled
998	  writes into TRBE registers TRBLIMITR_EL1, TRBPTR_EL1, TRBBASER_EL1, TRBSR_EL1,
999	  and TRBTRG_EL1 will be ignored and will not be effected.
1000
1001	  Work around this in the driver by executing TSB CSYNC and DSB after collection
1002	  is stopped and before performing a system register write to one of the affected
1003	  registers.
1004
1005	  If unsure, say Y.
1006
1007config ARM64_ERRATUM_2038923
1008	bool "Cortex-A510: 2038923: workaround TRBE corruption with enable"
1009	depends on CORESIGHT_TRBE
1010	default y
1011	help
1012	  This option adds the workaround for ARM Cortex-A510 erratum 2038923.
1013
1014	  Affected Cortex-A510 core might cause an inconsistent view on whether trace is
1015	  prohibited within the CPU. As a result, the trace buffer or trace buffer state
1016	  might be corrupted. This happens after TRBE buffer has been enabled by setting
1017	  TRBLIMITR_EL1.E, followed by just a single context synchronization event before
1018	  execution changes from a context, in which trace is prohibited to one where it
1019	  isn't, or vice versa. In these mentioned conditions, the view of whether trace
1020	  is prohibited is inconsistent between parts of the CPU, and the trace buffer or
1021	  the trace buffer state might be corrupted.
1022
1023	  Work around this in the driver by preventing an inconsistent view of whether the
1024	  trace is prohibited or not based on TRBLIMITR_EL1.E by immediately following a
1025	  change to TRBLIMITR_EL1.E with at least one ISB instruction before an ERET, or
1026	  two ISB instructions if no ERET is to take place.
1027
1028	  If unsure, say Y.
1029
1030config ARM64_ERRATUM_1902691
1031	bool "Cortex-A510: 1902691: workaround TRBE trace corruption"
1032	depends on CORESIGHT_TRBE
1033	default y
1034	help
1035	  This option adds the workaround for ARM Cortex-A510 erratum 1902691.
1036
1037	  Affected Cortex-A510 core might cause trace data corruption, when being written
1038	  into the memory. Effectively TRBE is broken and hence cannot be used to capture
1039	  trace data.
1040
1041	  Work around this problem in the driver by just preventing TRBE initialization on
1042	  affected cpus. The firmware must have disabled the access to TRBE for the kernel
1043	  on such implementations. This will cover the kernel for any firmware that doesn't
1044	  do this already.
1045
1046	  If unsure, say Y.
1047
1048config ARM64_ERRATUM_2457168
1049	bool "Cortex-A510: 2457168: workaround for AMEVCNTR01 incrementing incorrectly"
1050	depends on ARM64_AMU_EXTN
1051	default y
1052	help
1053	  This option adds the workaround for ARM Cortex-A510 erratum 2457168.
1054
1055	  The AMU counter AMEVCNTR01 (constant counter) should increment at the same rate
1056	  as the system counter. On affected Cortex-A510 cores AMEVCNTR01 increments
1057	  incorrectly giving a significantly higher output value.
1058
1059	  Work around this problem by returning 0 when reading the affected counter in
1060	  key locations that results in disabling all users of this counter. This effect
1061	  is the same to firmware disabling affected counters.
1062
1063	  If unsure, say Y.
1064
1065config ARM64_ERRATUM_2645198
1066	bool "Cortex-A715: 2645198: Workaround possible [ESR|FAR]_ELx corruption"
1067	default y
1068	help
1069	  This option adds the workaround for ARM Cortex-A715 erratum 2645198.
1070
1071	  If a Cortex-A715 cpu sees a page mapping permissions change from executable
1072	  to non-executable, it may corrupt the ESR_ELx and FAR_ELx registers on the
1073	  next instruction abort caused by permission fault.
1074
1075	  Only user-space does executable to non-executable permission transition via
1076	  mprotect() system call. Workaround the problem by doing a break-before-make
1077	  TLB invalidation, for all changes to executable user space mappings.
1078
1079	  If unsure, say Y.
1080
1081config ARM64_WORKAROUND_SPECULATIVE_UNPRIV_LOAD
1082	bool
1083
1084config ARM64_ERRATUM_2966298
1085	bool "Cortex-A520: 2966298: workaround for speculatively executed unprivileged load"
1086	select ARM64_WORKAROUND_SPECULATIVE_UNPRIV_LOAD
1087	default y
1088	help
1089	  This option adds the workaround for ARM Cortex-A520 erratum 2966298.
1090
1091	  On an affected Cortex-A520 core, a speculatively executed unprivileged
1092	  load might leak data from a privileged level via a cache side channel.
1093
1094	  Work around this problem by executing a TLBI before returning to EL0.
1095
1096	  If unsure, say Y.
1097
1098config ARM64_ERRATUM_3117295
1099	bool "Cortex-A510: 3117295: workaround for speculatively executed unprivileged load"
1100	select ARM64_WORKAROUND_SPECULATIVE_UNPRIV_LOAD
1101	default y
1102	help
1103	  This option adds the workaround for ARM Cortex-A510 erratum 3117295.
1104
1105	  On an affected Cortex-A510 core, a speculatively executed unprivileged
1106	  load might leak data from a privileged level via a cache side channel.
1107
1108	  Work around this problem by executing a TLBI before returning to EL0.
1109
1110	  If unsure, say Y.
1111
1112config ARM64_ERRATUM_3194386
1113	bool "Cortex-*/Neoverse-*: workaround for MSR SSBS not self-synchronizing"
1114	default y
1115	help
1116	  This option adds the workaround for the following errata:
1117
1118	  * ARM Cortex-A76 erratum 3324349
1119	  * ARM Cortex-A77 erratum 3324348
1120	  * ARM Cortex-A78 erratum 3324344
1121	  * ARM Cortex-A78C erratum 3324346
1122	  * ARM Cortex-A78C erratum 3324347
1123	  * ARM Cortex-A710 erratam 3324338
1124	  * ARM Cortex-A715 errartum 3456084
1125	  * ARM Cortex-A720 erratum 3456091
1126	  * ARM Cortex-A725 erratum 3456106
1127	  * ARM Cortex-X1 erratum 3324344
1128	  * ARM Cortex-X1C erratum 3324346
1129	  * ARM Cortex-X2 erratum 3324338
1130	  * ARM Cortex-X3 erratum 3324335
1131	  * ARM Cortex-X4 erratum 3194386
1132	  * ARM Cortex-X925 erratum 3324334
1133	  * ARM Neoverse-N1 erratum 3324349
1134	  * ARM Neoverse N2 erratum 3324339
1135	  * ARM Neoverse-N3 erratum 3456111
1136	  * ARM Neoverse-V1 erratum 3324341
1137	  * ARM Neoverse V2 erratum 3324336
1138	  * ARM Neoverse-V3 erratum 3312417
1139
1140	  On affected cores "MSR SSBS, #0" instructions may not affect
1141	  subsequent speculative instructions, which may permit unexepected
1142	  speculative store bypassing.
1143
1144	  Work around this problem by placing a Speculation Barrier (SB) or
1145	  Instruction Synchronization Barrier (ISB) after kernel changes to
1146	  SSBS. The presence of the SSBS special-purpose register is hidden
1147	  from hwcaps and EL0 reads of ID_AA64PFR1_EL1, such that userspace
1148	  will use the PR_SPEC_STORE_BYPASS prctl to change SSBS.
1149
1150	  If unsure, say Y.
1151
1152config CAVIUM_ERRATUM_22375
1153	bool "Cavium erratum 22375, 24313"
1154	default y
1155	help
1156	  Enable workaround for errata 22375 and 24313.
1157
1158	  This implements two gicv3-its errata workarounds for ThunderX. Both
1159	  with a small impact affecting only ITS table allocation.
1160
1161	    erratum 22375: only alloc 8MB table size
1162	    erratum 24313: ignore memory access type
1163
1164	  The fixes are in ITS initialization and basically ignore memory access
1165	  type and table size provided by the TYPER and BASER registers.
1166
1167	  If unsure, say Y.
1168
1169config CAVIUM_ERRATUM_23144
1170	bool "Cavium erratum 23144: ITS SYNC hang on dual socket system"
1171	depends on NUMA
1172	default y
1173	help
1174	  ITS SYNC command hang for cross node io and collections/cpu mapping.
1175
1176	  If unsure, say Y.
1177
1178config CAVIUM_ERRATUM_23154
1179	bool "Cavium errata 23154 and 38545: GICv3 lacks HW synchronisation"
1180	default y
1181	help
1182	  The ThunderX GICv3 implementation requires a modified version for
1183	  reading the IAR status to ensure data synchronization
1184	  (access to icc_iar1_el1 is not sync'ed before and after).
1185
1186	  It also suffers from erratum 38545 (also present on Marvell's
1187	  OcteonTX and OcteonTX2), resulting in deactivated interrupts being
1188	  spuriously presented to the CPU interface.
1189
1190	  If unsure, say Y.
1191
1192config CAVIUM_ERRATUM_27456
1193	bool "Cavium erratum 27456: Broadcast TLBI instructions may cause icache corruption"
1194	default y
1195	help
1196	  On ThunderX T88 pass 1.x through 2.1 parts, broadcast TLBI
1197	  instructions may cause the icache to become corrupted if it
1198	  contains data for a non-current ASID.  The fix is to
1199	  invalidate the icache when changing the mm context.
1200
1201	  If unsure, say Y.
1202
1203config CAVIUM_ERRATUM_30115
1204	bool "Cavium erratum 30115: Guest may disable interrupts in host"
1205	default y
1206	help
1207	  On ThunderX T88 pass 1.x through 2.2, T81 pass 1.0 through
1208	  1.2, and T83 Pass 1.0, KVM guest execution may disable
1209	  interrupts in host. Trapping both GICv3 group-0 and group-1
1210	  accesses sidesteps the issue.
1211
1212	  If unsure, say Y.
1213
1214config CAVIUM_TX2_ERRATUM_219
1215	bool "Cavium ThunderX2 erratum 219: PRFM between TTBR change and ISB fails"
1216	default y
1217	help
1218	  On Cavium ThunderX2, a load, store or prefetch instruction between a
1219	  TTBR update and the corresponding context synchronizing operation can
1220	  cause a spurious Data Abort to be delivered to any hardware thread in
1221	  the CPU core.
1222
1223	  Work around the issue by avoiding the problematic code sequence and
1224	  trapping KVM guest TTBRx_EL1 writes to EL2 when SMT is enabled. The
1225	  trap handler performs the corresponding register access, skips the
1226	  instruction and ensures context synchronization by virtue of the
1227	  exception return.
1228
1229	  If unsure, say Y.
1230
1231config FUJITSU_ERRATUM_010001
1232	bool "Fujitsu-A64FX erratum E#010001: Undefined fault may occur wrongly"
1233	default y
1234	help
1235	  This option adds a workaround for Fujitsu-A64FX erratum E#010001.
1236	  On some variants of the Fujitsu-A64FX cores ver(1.0, 1.1), memory
1237	  accesses may cause undefined fault (Data abort, DFSC=0b111111).
1238	  This fault occurs under a specific hardware condition when a
1239	  load/store instruction performs an address translation using:
1240	  case-1  TTBR0_EL1 with TCR_EL1.NFD0 == 1.
1241	  case-2  TTBR0_EL2 with TCR_EL2.NFD0 == 1.
1242	  case-3  TTBR1_EL1 with TCR_EL1.NFD1 == 1.
1243	  case-4  TTBR1_EL2 with TCR_EL2.NFD1 == 1.
1244
1245	  The workaround is to ensure these bits are clear in TCR_ELx.
1246	  The workaround only affects the Fujitsu-A64FX.
1247
1248	  If unsure, say Y.
1249
1250config HISILICON_ERRATUM_161600802
1251	bool "Hip07 161600802: Erroneous redistributor VLPI base"
1252	default y
1253	help
1254	  The HiSilicon Hip07 SoC uses the wrong redistributor base
1255	  when issued ITS commands such as VMOVP and VMAPP, and requires
1256	  a 128kB offset to be applied to the target address in this commands.
1257
1258	  If unsure, say Y.
1259
1260config HISILICON_ERRATUM_162100801
1261	bool "Hip09 162100801 erratum support"
1262	default y
1263	help
1264	  When enabling GICv4.1 in hip09, VMAPP will fail to clear some caches
1265	  during unmapping operation, which will cause some vSGIs lost.
1266	  To fix the issue, invalidate related vPE cache through GICR_INVALLR
1267	  after VMOVP.
1268
1269	  If unsure, say Y.
1270
1271config QCOM_FALKOR_ERRATUM_1003
1272	bool "Falkor E1003: Incorrect translation due to ASID change"
1273	default y
1274	help
1275	  On Falkor v1, an incorrect ASID may be cached in the TLB when ASID
1276	  and BADDR are changed together in TTBRx_EL1. Since we keep the ASID
1277	  in TTBR1_EL1, this situation only occurs in the entry trampoline and
1278	  then only for entries in the walk cache, since the leaf translation
1279	  is unchanged. Work around the erratum by invalidating the walk cache
1280	  entries for the trampoline before entering the kernel proper.
1281
1282config QCOM_FALKOR_ERRATUM_1009
1283	bool "Falkor E1009: Prematurely complete a DSB after a TLBI"
1284	default y
1285	select ARM64_WORKAROUND_REPEAT_TLBI
1286	help
1287	  On Falkor v1, the CPU may prematurely complete a DSB following a
1288	  TLBI xxIS invalidate maintenance operation. Repeat the TLBI operation
1289	  one more time to fix the issue.
1290
1291	  If unsure, say Y.
1292
1293config QCOM_QDF2400_ERRATUM_0065
1294	bool "QDF2400 E0065: Incorrect GITS_TYPER.ITT_Entry_size"
1295	default y
1296	help
1297	  On Qualcomm Datacenter Technologies QDF2400 SoC, ITS hardware reports
1298	  ITE size incorrectly. The GITS_TYPER.ITT_Entry_size field should have
1299	  been indicated as 16Bytes (0xf), not 8Bytes (0x7).
1300
1301	  If unsure, say Y.
1302
1303config QCOM_FALKOR_ERRATUM_E1041
1304	bool "Falkor E1041: Speculative instruction fetches might cause errant memory access"
1305	default y
1306	help
1307	  Falkor CPU may speculatively fetch instructions from an improper
1308	  memory location when MMU translation is changed from SCTLR_ELn[M]=1
1309	  to SCTLR_ELn[M]=0. Prefix an ISB instruction to fix the problem.
1310
1311	  If unsure, say Y.
1312
1313config NVIDIA_CARMEL_CNP_ERRATUM
1314	bool "NVIDIA Carmel CNP: CNP on Carmel semantically different than ARM cores"
1315	default y
1316	help
1317	  If CNP is enabled on Carmel cores, non-sharable TLBIs on a core will not
1318	  invalidate shared TLB entries installed by a different core, as it would
1319	  on standard ARM cores.
1320
1321	  If unsure, say Y.
1322
1323config ROCKCHIP_ERRATUM_3568002
1324	bool "Rockchip 3568002: GIC600 can not access physical addresses higher than 4GB"
1325	default y
1326	help
1327	  The Rockchip RK3566 and RK3568 GIC600 SoC integrations have AXI
1328	  addressing limited to the first 32bit of physical address space.
1329
1330	  If unsure, say Y.
1331
1332config ROCKCHIP_ERRATUM_3588001
1333	bool "Rockchip 3588001: GIC600 can not support shareability attributes"
1334	default y
1335	help
1336	  The Rockchip RK3588 GIC600 SoC integration does not support ACE/ACE-lite.
1337	  This means, that its sharability feature may not be used, even though it
1338	  is supported by the IP itself.
1339
1340	  If unsure, say Y.
1341
1342config SOCIONEXT_SYNQUACER_PREITS
1343	bool "Socionext Synquacer: Workaround for GICv3 pre-ITS"
1344	default y
1345	help
1346	  Socionext Synquacer SoCs implement a separate h/w block to generate
1347	  MSI doorbell writes with non-zero values for the device ID.
1348
1349	  If unsure, say Y.
1350
1351endmenu # "ARM errata workarounds via the alternatives framework"
1352
1353choice
1354	prompt "Page size"
1355	default ARM64_4K_PAGES
1356	help
1357	  Page size (translation granule) configuration.
1358
1359config ARM64_4K_PAGES
1360	bool "4KB"
1361	select HAVE_PAGE_SIZE_4KB
1362	help
1363	  This feature enables 4KB pages support.
1364
1365config ARM64_16K_PAGES
1366	bool "16KB"
1367	select HAVE_PAGE_SIZE_16KB
1368	help
1369	  The system will use 16KB pages support. AArch32 emulation
1370	  requires applications compiled with 16K (or a multiple of 16K)
1371	  aligned segments.
1372
1373config ARM64_64K_PAGES
1374	bool "64KB"
1375	select HAVE_PAGE_SIZE_64KB
1376	help
1377	  This feature enables 64KB pages support (4KB by default)
1378	  allowing only two levels of page tables and faster TLB
1379	  look-up. AArch32 emulation requires applications compiled
1380	  with 64K aligned segments.
1381
1382endchoice
1383
1384choice
1385	prompt "Virtual address space size"
1386	default ARM64_VA_BITS_52
1387	help
1388	  Allows choosing one of multiple possible virtual address
1389	  space sizes. The level of translation table is determined by
1390	  a combination of page size and virtual address space size.
1391
1392config ARM64_VA_BITS_36
1393	bool "36-bit" if EXPERT
1394	depends on PAGE_SIZE_16KB
1395
1396config ARM64_VA_BITS_39
1397	bool "39-bit"
1398	depends on PAGE_SIZE_4KB
1399
1400config ARM64_VA_BITS_42
1401	bool "42-bit"
1402	depends on PAGE_SIZE_64KB
1403
1404config ARM64_VA_BITS_47
1405	bool "47-bit"
1406	depends on PAGE_SIZE_16KB
1407
1408config ARM64_VA_BITS_48
1409	bool "48-bit"
1410
1411config ARM64_VA_BITS_52
1412	bool "52-bit"
1413	help
1414	  Enable 52-bit virtual addressing for userspace when explicitly
1415	  requested via a hint to mmap(). The kernel will also use 52-bit
1416	  virtual addresses for its own mappings (provided HW support for
1417	  this feature is available, otherwise it reverts to 48-bit).
1418
1419	  NOTE: Enabling 52-bit virtual addressing in conjunction with
1420	  ARMv8.3 Pointer Authentication will result in the PAC being
1421	  reduced from 7 bits to 3 bits, which may have a significant
1422	  impact on its susceptibility to brute-force attacks.
1423
1424	  If unsure, select 48-bit virtual addressing instead.
1425
1426endchoice
1427
1428config ARM64_FORCE_52BIT
1429	bool "Force 52-bit virtual addresses for userspace"
1430	depends on ARM64_VA_BITS_52 && EXPERT
1431	help
1432	  For systems with 52-bit userspace VAs enabled, the kernel will attempt
1433	  to maintain compatibility with older software by providing 48-bit VAs
1434	  unless a hint is supplied to mmap.
1435
1436	  This configuration option disables the 48-bit compatibility logic, and
1437	  forces all userspace addresses to be 52-bit on HW that supports it. One
1438	  should only enable this configuration option for stress testing userspace
1439	  memory management code. If unsure say N here.
1440
1441config ARM64_VA_BITS
1442	int
1443	default 36 if ARM64_VA_BITS_36
1444	default 39 if ARM64_VA_BITS_39
1445	default 42 if ARM64_VA_BITS_42
1446	default 47 if ARM64_VA_BITS_47
1447	default 48 if ARM64_VA_BITS_48
1448	default 52 if ARM64_VA_BITS_52
1449
1450choice
1451	prompt "Physical address space size"
1452	default ARM64_PA_BITS_48
1453	help
1454	  Choose the maximum physical address range that the kernel will
1455	  support.
1456
1457config ARM64_PA_BITS_48
1458	bool "48-bit"
1459	depends on ARM64_64K_PAGES || !ARM64_VA_BITS_52
1460
1461config ARM64_PA_BITS_52
1462	bool "52-bit"
1463	depends on ARM64_64K_PAGES || ARM64_VA_BITS_52
1464	help
1465	  Enable support for a 52-bit physical address space, introduced as
1466	  part of the ARMv8.2-LPA extension.
1467
1468	  With this enabled, the kernel will also continue to work on CPUs that
1469	  do not support ARMv8.2-LPA, but with some added memory overhead (and
1470	  minor performance overhead).
1471
1472endchoice
1473
1474config ARM64_PA_BITS
1475	int
1476	default 48 if ARM64_PA_BITS_48
1477	default 52 if ARM64_PA_BITS_52
1478
1479config ARM64_LPA2
1480	def_bool y
1481	depends on ARM64_PA_BITS_52 && !ARM64_64K_PAGES
1482
1483choice
1484	prompt "Endianness"
1485	default CPU_LITTLE_ENDIAN
1486	help
1487	  Select the endianness of data accesses performed by the CPU. Userspace
1488	  applications will need to be compiled and linked for the endianness
1489	  that is selected here.
1490
1491config CPU_BIG_ENDIAN
1492	bool "Build big-endian kernel"
1493	# https://github.com/llvm/llvm-project/commit/1379b150991f70a5782e9a143c2ba5308da1161c
1494	depends on AS_IS_GNU || AS_VERSION >= 150000
1495	help
1496	  Say Y if you plan on running a kernel with a big-endian userspace.
1497
1498config CPU_LITTLE_ENDIAN
1499	bool "Build little-endian kernel"
1500	help
1501	  Say Y if you plan on running a kernel with a little-endian userspace.
1502	  This is usually the case for distributions targeting arm64.
1503
1504endchoice
1505
1506config SCHED_MC
1507	bool "Multi-core scheduler support"
1508	help
1509	  Multi-core scheduler support improves the CPU scheduler's decision
1510	  making when dealing with multi-core CPU chips at a cost of slightly
1511	  increased overhead in some places. If unsure say N here.
1512
1513config SCHED_CLUSTER
1514	bool "Cluster scheduler support"
1515	help
1516	  Cluster scheduler support improves the CPU scheduler's decision
1517	  making when dealing with machines that have clusters of CPUs.
1518	  Cluster usually means a couple of CPUs which are placed closely
1519	  by sharing mid-level caches, last-level cache tags or internal
1520	  busses.
1521
1522config SCHED_SMT
1523	bool "SMT scheduler support"
1524	help
1525	  Improves the CPU scheduler's decision making when dealing with
1526	  MultiThreading at a cost of slightly increased overhead in some
1527	  places. If unsure say N here.
1528
1529config NR_CPUS
1530	int "Maximum number of CPUs (2-4096)"
1531	range 2 4096
1532	default "512"
1533
1534config HOTPLUG_CPU
1535	bool "Support for hot-pluggable CPUs"
1536	select GENERIC_IRQ_MIGRATION
1537	help
1538	  Say Y here to experiment with turning CPUs off and on.  CPUs
1539	  can be controlled through /sys/devices/system/cpu.
1540
1541# Common NUMA Features
1542config NUMA
1543	bool "NUMA Memory Allocation and Scheduler Support"
1544	select GENERIC_ARCH_NUMA
1545	select OF_NUMA
1546	select HAVE_SETUP_PER_CPU_AREA
1547	select NEED_PER_CPU_EMBED_FIRST_CHUNK
1548	select NEED_PER_CPU_PAGE_FIRST_CHUNK
1549	select USE_PERCPU_NUMA_NODE_ID
1550	help
1551	  Enable NUMA (Non-Uniform Memory Access) support.
1552
1553	  The kernel will try to allocate memory used by a CPU on the
1554	  local memory of the CPU and add some more
1555	  NUMA awareness to the kernel.
1556
1557config NODES_SHIFT
1558	int "Maximum NUMA Nodes (as a power of 2)"
1559	range 1 10
1560	default "4"
1561	depends on NUMA
1562	help
1563	  Specify the maximum number of NUMA Nodes available on the target
1564	  system.  Increases memory reserved to accommodate various tables.
1565
1566source "kernel/Kconfig.hz"
1567
1568config ARCH_SPARSEMEM_ENABLE
1569	def_bool y
1570	select SPARSEMEM_VMEMMAP_ENABLE
1571	select SPARSEMEM_VMEMMAP
1572
1573config HW_PERF_EVENTS
1574	def_bool y
1575	depends on ARM_PMU
1576
1577# Supported by clang >= 7.0 or GCC >= 12.0.0
1578config CC_HAVE_SHADOW_CALL_STACK
1579	def_bool $(cc-option, -fsanitize=shadow-call-stack -ffixed-x18)
1580
1581config PARAVIRT
1582	bool "Enable paravirtualization code"
1583	help
1584	  This changes the kernel so it can modify itself when it is run
1585	  under a hypervisor, potentially improving performance significantly
1586	  over full virtualization.
1587
1588config PARAVIRT_TIME_ACCOUNTING
1589	bool "Paravirtual steal time accounting"
1590	select PARAVIRT
1591	help
1592	  Select this option to enable fine granularity task steal time
1593	  accounting. Time spent executing other tasks in parallel with
1594	  the current vCPU is discounted from the vCPU power. To account for
1595	  that, there can be a small performance impact.
1596
1597	  If in doubt, say N here.
1598
1599config ARCH_SUPPORTS_KEXEC
1600	def_bool PM_SLEEP_SMP
1601
1602config ARCH_SUPPORTS_KEXEC_FILE
1603	def_bool y
1604
1605config ARCH_SELECTS_KEXEC_FILE
1606	def_bool y
1607	depends on KEXEC_FILE
1608	select HAVE_IMA_KEXEC if IMA
1609
1610config ARCH_SUPPORTS_KEXEC_SIG
1611	def_bool y
1612
1613config ARCH_SUPPORTS_KEXEC_IMAGE_VERIFY_SIG
1614	def_bool y
1615
1616config ARCH_DEFAULT_KEXEC_IMAGE_VERIFY_SIG
1617	def_bool y
1618
1619config ARCH_SUPPORTS_KEXEC_HANDOVER
1620	def_bool y
1621
1622config ARCH_SUPPORTS_CRASH_DUMP
1623	def_bool y
1624
1625config ARCH_DEFAULT_CRASH_DUMP
1626	def_bool y
1627
1628config ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION
1629	def_bool CRASH_RESERVE
1630
1631config TRANS_TABLE
1632	def_bool y
1633	depends on HIBERNATION || KEXEC_CORE
1634
1635config XEN_DOM0
1636	def_bool y
1637	depends on XEN
1638
1639config XEN
1640	bool "Xen guest support on ARM64"
1641	depends on ARM64 && OF
1642	select SWIOTLB_XEN
1643	select PARAVIRT
1644	help
1645	  Say Y if you want to run Linux in a Virtual Machine on Xen on ARM64.
1646
1647# include/linux/mmzone.h requires the following to be true:
1648#
1649#   MAX_PAGE_ORDER + PAGE_SHIFT <= SECTION_SIZE_BITS
1650#
1651# so the maximum value of MAX_PAGE_ORDER is SECTION_SIZE_BITS - PAGE_SHIFT:
1652#
1653#     | SECTION_SIZE_BITS |  PAGE_SHIFT  |  max MAX_PAGE_ORDER  |  default MAX_PAGE_ORDER |
1654# ----+-------------------+--------------+----------------------+-------------------------+
1655# 4K  |       27          |      12      |       15             |         10              |
1656# 16K |       27          |      14      |       13             |         11              |
1657# 64K |       29          |      16      |       13             |         13              |
1658config ARCH_FORCE_MAX_ORDER
1659	int
1660	default "13" if ARM64_64K_PAGES
1661	default "11" if ARM64_16K_PAGES
1662	default "10"
1663	help
1664	  The kernel page allocator limits the size of maximal physically
1665	  contiguous allocations. The limit is called MAX_PAGE_ORDER and it
1666	  defines the maximal power of two of number of pages that can be
1667	  allocated as a single contiguous block. This option allows
1668	  overriding the default setting when ability to allocate very
1669	  large blocks of physically contiguous memory is required.
1670
1671	  The maximal size of allocation cannot exceed the size of the
1672	  section, so the value of MAX_PAGE_ORDER should satisfy
1673
1674	    MAX_PAGE_ORDER + PAGE_SHIFT <= SECTION_SIZE_BITS
1675
1676	  Don't change if unsure.
1677
1678config UNMAP_KERNEL_AT_EL0
1679	bool "Unmap kernel when running in userspace (KPTI)" if EXPERT
1680	default y
1681	help
1682	  Speculation attacks against some high-performance processors can
1683	  be used to bypass MMU permission checks and leak kernel data to
1684	  userspace. This can be defended against by unmapping the kernel
1685	  when running in userspace, mapping it back in on exception entry
1686	  via a trampoline page in the vector table.
1687
1688	  If unsure, say Y.
1689
1690config MITIGATE_SPECTRE_BRANCH_HISTORY
1691	bool "Mitigate Spectre style attacks against branch history" if EXPERT
1692	default y
1693	help
1694	  Speculation attacks against some high-performance processors can
1695	  make use of branch history to influence future speculation.
1696	  When taking an exception from user-space, a sequence of branches
1697	  or a firmware call overwrites the branch history.
1698
1699config RODATA_FULL_DEFAULT_ENABLED
1700	bool "Apply r/o permissions of VM areas also to their linear aliases"
1701	default y
1702	help
1703	  Apply read-only attributes of VM areas to the linear alias of
1704	  the backing pages as well. This prevents code or read-only data
1705	  from being modified (inadvertently or intentionally) via another
1706	  mapping of the same memory page. This additional enhancement can
1707	  be turned off at runtime by passing rodata=[off|on] (and turned on
1708	  with rodata=full if this option is set to 'n')
1709
1710	  This requires the linear region to be mapped down to pages,
1711	  which may adversely affect performance in some cases.
1712
1713config ARM64_SW_TTBR0_PAN
1714	bool "Emulate Privileged Access Never using TTBR0_EL1 switching"
1715	depends on !KCSAN
1716	select ARM64_PAN
1717	help
1718	  Enabling this option prevents the kernel from accessing
1719	  user-space memory directly by pointing TTBR0_EL1 to a reserved
1720	  zeroed area and reserved ASID. The user access routines
1721	  restore the valid TTBR0_EL1 temporarily.
1722
1723config ARM64_TAGGED_ADDR_ABI
1724	bool "Enable the tagged user addresses syscall ABI"
1725	default y
1726	help
1727	  When this option is enabled, user applications can opt in to a
1728	  relaxed ABI via prctl() allowing tagged addresses to be passed
1729	  to system calls as pointer arguments. For details, see
1730	  Documentation/arch/arm64/tagged-address-abi.rst.
1731
1732menuconfig COMPAT
1733	bool "Kernel support for 32-bit EL0"
1734	depends on ARM64_4K_PAGES || EXPERT
1735	select HAVE_UID16
1736	select OLD_SIGSUSPEND3
1737	select COMPAT_OLD_SIGACTION
1738	help
1739	  This option enables support for a 32-bit EL0 running under a 64-bit
1740	  kernel at EL1. AArch32-specific components such as system calls,
1741	  the user helper functions, VFP support and the ptrace interface are
1742	  handled appropriately by the kernel.
1743
1744	  If you use a page size other than 4KB (i.e, 16KB or 64KB), please be aware
1745	  that you will only be able to execute AArch32 binaries that were compiled
1746	  with page size aligned segments.
1747
1748	  If you want to execute 32-bit userspace applications, say Y.
1749
1750if COMPAT
1751
1752config KUSER_HELPERS
1753	bool "Enable kuser helpers page for 32-bit applications"
1754	default y
1755	help
1756	  Warning: disabling this option may break 32-bit user programs.
1757
1758	  Provide kuser helpers to compat tasks. The kernel provides
1759	  helper code to userspace in read only form at a fixed location
1760	  to allow userspace to be independent of the CPU type fitted to
1761	  the system. This permits binaries to be run on ARMv4 through
1762	  to ARMv8 without modification.
1763
1764	  See Documentation/arch/arm/kernel_user_helpers.rst for details.
1765
1766	  However, the fixed address nature of these helpers can be used
1767	  by ROP (return orientated programming) authors when creating
1768	  exploits.
1769
1770	  If all of the binaries and libraries which run on your platform
1771	  are built specifically for your platform, and make no use of
1772	  these helpers, then you can turn this option off to hinder
1773	  such exploits. However, in that case, if a binary or library
1774	  relying on those helpers is run, it will not function correctly.
1775
1776	  Say N here only if you are absolutely certain that you do not
1777	  need these helpers; otherwise, the safe option is to say Y.
1778
1779config COMPAT_VDSO
1780	bool "Enable vDSO for 32-bit applications"
1781	depends on !CPU_BIG_ENDIAN
1782	depends on (CC_IS_CLANG && LD_IS_LLD) || "$(CROSS_COMPILE_COMPAT)" != ""
1783	select GENERIC_COMPAT_VDSO
1784	default y
1785	help
1786	  Place in the process address space of 32-bit applications an
1787	  ELF shared object providing fast implementations of gettimeofday
1788	  and clock_gettime.
1789
1790	  You must have a 32-bit build of glibc 2.22 or later for programs
1791	  to seamlessly take advantage of this.
1792
1793config THUMB2_COMPAT_VDSO
1794	bool "Compile the 32-bit vDSO for Thumb-2 mode" if EXPERT
1795	depends on COMPAT_VDSO
1796	default y
1797	help
1798	  Compile the compat vDSO with '-mthumb -fomit-frame-pointer' if y,
1799	  otherwise with '-marm'.
1800
1801config COMPAT_ALIGNMENT_FIXUPS
1802	bool "Fix up misaligned multi-word loads and stores in user space"
1803
1804menuconfig ARMV8_DEPRECATED
1805	bool "Emulate deprecated/obsolete ARMv8 instructions"
1806	depends on SYSCTL
1807	help
1808	  Legacy software support may require certain instructions
1809	  that have been deprecated or obsoleted in the architecture.
1810
1811	  Enable this config to enable selective emulation of these
1812	  features.
1813
1814	  If unsure, say Y
1815
1816if ARMV8_DEPRECATED
1817
1818config SWP_EMULATION
1819	bool "Emulate SWP/SWPB instructions"
1820	help
1821	  ARMv8 obsoletes the use of A32 SWP/SWPB instructions such that
1822	  they are always undefined. Say Y here to enable software
1823	  emulation of these instructions for userspace using LDXR/STXR.
1824	  This feature can be controlled at runtime with the abi.swp
1825	  sysctl which is disabled by default.
1826
1827	  In some older versions of glibc [<=2.8] SWP is used during futex
1828	  trylock() operations with the assumption that the code will not
1829	  be preempted. This invalid assumption may be more likely to fail
1830	  with SWP emulation enabled, leading to deadlock of the user
1831	  application.
1832
1833	  NOTE: when accessing uncached shared regions, LDXR/STXR rely
1834	  on an external transaction monitoring block called a global
1835	  monitor to maintain update atomicity. If your system does not
1836	  implement a global monitor, this option can cause programs that
1837	  perform SWP operations to uncached memory to deadlock.
1838
1839	  If unsure, say Y
1840
1841config CP15_BARRIER_EMULATION
1842	bool "Emulate CP15 Barrier instructions"
1843	help
1844	  The CP15 barrier instructions - CP15ISB, CP15DSB, and
1845	  CP15DMB - are deprecated in ARMv8 (and ARMv7). It is
1846	  strongly recommended to use the ISB, DSB, and DMB
1847	  instructions instead.
1848
1849	  Say Y here to enable software emulation of these
1850	  instructions for AArch32 userspace code. When this option is
1851	  enabled, CP15 barrier usage is traced which can help
1852	  identify software that needs updating. This feature can be
1853	  controlled at runtime with the abi.cp15_barrier sysctl.
1854
1855	  If unsure, say Y
1856
1857config SETEND_EMULATION
1858	bool "Emulate SETEND instruction"
1859	help
1860	  The SETEND instruction alters the data-endianness of the
1861	  AArch32 EL0, and is deprecated in ARMv8.
1862
1863	  Say Y here to enable software emulation of the instruction
1864	  for AArch32 userspace code. This feature can be controlled
1865	  at runtime with the abi.setend sysctl.
1866
1867	  Note: All the cpus on the system must have mixed endian support at EL0
1868	  for this feature to be enabled. If a new CPU - which doesn't support mixed
1869	  endian - is hotplugged in after this feature has been enabled, there could
1870	  be unexpected results in the applications.
1871
1872	  If unsure, say Y
1873endif # ARMV8_DEPRECATED
1874
1875endif # COMPAT
1876
1877menu "ARMv8.1 architectural features"
1878
1879config ARM64_HW_AFDBM
1880	bool "Support for hardware updates of the Access and Dirty page flags"
1881	default y
1882	help
1883	  The ARMv8.1 architecture extensions introduce support for
1884	  hardware updates of the access and dirty information in page
1885	  table entries. When enabled in TCR_EL1 (HA and HD bits) on
1886	  capable processors, accesses to pages with PTE_AF cleared will
1887	  set this bit instead of raising an access flag fault.
1888	  Similarly, writes to read-only pages with the DBM bit set will
1889	  clear the read-only bit (AP[2]) instead of raising a
1890	  permission fault.
1891
1892	  Kernels built with this configuration option enabled continue
1893	  to work on pre-ARMv8.1 hardware and the performance impact is
1894	  minimal. If unsure, say Y.
1895
1896config ARM64_PAN
1897	bool "Enable support for Privileged Access Never (PAN)"
1898	default y
1899	help
1900	  Privileged Access Never (PAN; part of the ARMv8.1 Extensions)
1901	  prevents the kernel or hypervisor from accessing user-space (EL0)
1902	  memory directly.
1903
1904	  Choosing this option will cause any unprotected (not using
1905	  copy_to_user et al) memory access to fail with a permission fault.
1906
1907	  The feature is detected at runtime, and will remain as a 'nop'
1908	  instruction if the cpu does not implement the feature.
1909
1910config ARM64_LSE_ATOMICS
1911	bool
1912	default ARM64_USE_LSE_ATOMICS
1913
1914config ARM64_USE_LSE_ATOMICS
1915	bool "Atomic instructions"
1916	default y
1917	help
1918	  As part of the Large System Extensions, ARMv8.1 introduces new
1919	  atomic instructions that are designed specifically to scale in
1920	  very large systems.
1921
1922	  Say Y here to make use of these instructions for the in-kernel
1923	  atomic routines. This incurs a small overhead on CPUs that do
1924	  not support these instructions.
1925
1926endmenu # "ARMv8.1 architectural features"
1927
1928menu "ARMv8.2 architectural features"
1929
1930config ARM64_PMEM
1931	bool "Enable support for persistent memory"
1932	select ARCH_HAS_PMEM_API
1933	select ARCH_HAS_UACCESS_FLUSHCACHE
1934	help
1935	  Say Y to enable support for the persistent memory API based on the
1936	  ARMv8.2 DCPoP feature.
1937
1938	  The feature is detected at runtime, and the kernel will use DC CVAC
1939	  operations if DC CVAP is not supported (following the behaviour of
1940	  DC CVAP itself if the system does not define a point of persistence).
1941
1942config ARM64_RAS_EXTN
1943	bool "Enable support for RAS CPU Extensions"
1944	default y
1945	help
1946	  CPUs that support the Reliability, Availability and Serviceability
1947	  (RAS) Extensions, part of ARMv8.2 are able to track faults and
1948	  errors, classify them and report them to software.
1949
1950	  On CPUs with these extensions system software can use additional
1951	  barriers to determine if faults are pending and read the
1952	  classification from a new set of registers.
1953
1954	  Selecting this feature will allow the kernel to use these barriers
1955	  and access the new registers if the system supports the extension.
1956	  Platform RAS features may additionally depend on firmware support.
1957
1958config ARM64_CNP
1959	bool "Enable support for Common Not Private (CNP) translations"
1960	default y
1961	help
1962	  Common Not Private (CNP) allows translation table entries to
1963	  be shared between different PEs in the same inner shareable
1964	  domain, so the hardware can use this fact to optimise the
1965	  caching of such entries in the TLB.
1966
1967	  Selecting this option allows the CNP feature to be detected
1968	  at runtime, and does not affect PEs that do not implement
1969	  this feature.
1970
1971endmenu # "ARMv8.2 architectural features"
1972
1973menu "ARMv8.3 architectural features"
1974
1975config ARM64_PTR_AUTH
1976	bool "Enable support for pointer authentication"
1977	default y
1978	help
1979	  Pointer authentication (part of the ARMv8.3 Extensions) provides
1980	  instructions for signing and authenticating pointers against secret
1981	  keys, which can be used to mitigate Return Oriented Programming (ROP)
1982	  and other attacks.
1983
1984	  This option enables these instructions at EL0 (i.e. for userspace).
1985	  Choosing this option will cause the kernel to initialise secret keys
1986	  for each process at exec() time, with these keys being
1987	  context-switched along with the process.
1988
1989	  The feature is detected at runtime. If the feature is not present in
1990	  hardware it will not be advertised to userspace/KVM guest nor will it
1991	  be enabled.
1992
1993	  If the feature is present on the boot CPU but not on a late CPU, then
1994	  the late CPU will be parked. Also, if the boot CPU does not have
1995	  address auth and the late CPU has then the late CPU will still boot
1996	  but with the feature disabled. On such a system, this option should
1997	  not be selected.
1998
1999config ARM64_PTR_AUTH_KERNEL
2000	bool "Use pointer authentication for kernel"
2001	default y
2002	depends on ARM64_PTR_AUTH
2003	# Modern compilers insert a .note.gnu.property section note for PAC
2004	# which is only understood by binutils starting with version 2.33.1.
2005	depends on LD_IS_LLD || LD_VERSION >= 23301 || (CC_IS_GCC && GCC_VERSION < 90100)
2006	depends on !CC_IS_CLANG || AS_HAS_CFI_NEGATE_RA_STATE
2007	depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_ARGS)
2008	help
2009	  If the compiler supports the -mbranch-protection or
2010	  -msign-return-address flag (e.g. GCC 7 or later), then this option
2011	  will cause the kernel itself to be compiled with return address
2012	  protection. In this case, and if the target hardware is known to
2013	  support pointer authentication, then CONFIG_STACKPROTECTOR can be
2014	  disabled with minimal loss of protection.
2015
2016	  This feature works with FUNCTION_GRAPH_TRACER option only if
2017	  DYNAMIC_FTRACE_WITH_ARGS is enabled.
2018
2019config CC_HAS_BRANCH_PROT_PAC_RET
2020	# GCC 9 or later, clang 8 or later
2021	def_bool $(cc-option,-mbranch-protection=pac-ret+leaf)
2022
2023config AS_HAS_CFI_NEGATE_RA_STATE
2024	# binutils 2.34+
2025	def_bool $(as-instr,.cfi_startproc\n.cfi_negate_ra_state\n.cfi_endproc\n)
2026
2027endmenu # "ARMv8.3 architectural features"
2028
2029menu "ARMv8.4 architectural features"
2030
2031config ARM64_AMU_EXTN
2032	bool "Enable support for the Activity Monitors Unit CPU extension"
2033	default y
2034	help
2035	  The activity monitors extension is an optional extension introduced
2036	  by the ARMv8.4 CPU architecture. This enables support for version 1
2037	  of the activity monitors architecture, AMUv1.
2038
2039	  To enable the use of this extension on CPUs that implement it, say Y.
2040
2041	  Note that for architectural reasons, firmware _must_ implement AMU
2042	  support when running on CPUs that present the activity monitors
2043	  extension. The required support is present in:
2044	    * Version 1.5 and later of the ARM Trusted Firmware
2045
2046	  For kernels that have this configuration enabled but boot with broken
2047	  firmware, you may need to say N here until the firmware is fixed.
2048	  Otherwise you may experience firmware panics or lockups when
2049	  accessing the counter registers. Even if you are not observing these
2050	  symptoms, the values returned by the register reads might not
2051	  correctly reflect reality. Most commonly, the value read will be 0,
2052	  indicating that the counter is not enabled.
2053
2054config ARM64_TLB_RANGE
2055	bool "Enable support for tlbi range feature"
2056	default y
2057	help
2058	  ARMv8.4-TLBI provides TLBI invalidation instruction that apply to a
2059	  range of input addresses.
2060
2061endmenu # "ARMv8.4 architectural features"
2062
2063menu "ARMv8.5 architectural features"
2064
2065config AS_HAS_ARMV8_5
2066	def_bool $(cc-option,-Wa$(comma)-march=armv8.5-a)
2067
2068config ARM64_BTI
2069	bool "Branch Target Identification support"
2070	default y
2071	help
2072	  Branch Target Identification (part of the ARMv8.5 Extensions)
2073	  provides a mechanism to limit the set of locations to which computed
2074	  branch instructions such as BR or BLR can jump.
2075
2076	  To make use of BTI on CPUs that support it, say Y.
2077
2078	  BTI is intended to provide complementary protection to other control
2079	  flow integrity protection mechanisms, such as the Pointer
2080	  authentication mechanism provided as part of the ARMv8.3 Extensions.
2081	  For this reason, it does not make sense to enable this option without
2082	  also enabling support for pointer authentication.  Thus, when
2083	  enabling this option you should also select ARM64_PTR_AUTH=y.
2084
2085	  Userspace binaries must also be specifically compiled to make use of
2086	  this mechanism.  If you say N here or the hardware does not support
2087	  BTI, such binaries can still run, but you get no additional
2088	  enforcement of branch destinations.
2089
2090config ARM64_BTI_KERNEL
2091	bool "Use Branch Target Identification for kernel"
2092	default y
2093	depends on ARM64_BTI
2094	depends on ARM64_PTR_AUTH_KERNEL
2095	depends on CC_HAS_BRANCH_PROT_PAC_RET_BTI
2096	# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94697
2097	depends on !CC_IS_GCC || GCC_VERSION >= 100100
2098	# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106671
2099	depends on !CC_IS_GCC
2100	depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_ARGS)
2101	help
2102	  Build the kernel with Branch Target Identification annotations
2103	  and enable enforcement of this for kernel code. When this option
2104	  is enabled and the system supports BTI all kernel code including
2105	  modular code must have BTI enabled.
2106
2107config CC_HAS_BRANCH_PROT_PAC_RET_BTI
2108	# GCC 9 or later, clang 8 or later
2109	def_bool $(cc-option,-mbranch-protection=pac-ret+leaf+bti)
2110
2111config ARM64_E0PD
2112	bool "Enable support for E0PD"
2113	default y
2114	help
2115	  E0PD (part of the ARMv8.5 extensions) allows us to ensure
2116	  that EL0 accesses made via TTBR1 always fault in constant time,
2117	  providing similar benefits to KASLR as those provided by KPTI, but
2118	  with lower overhead and without disrupting legitimate access to
2119	  kernel memory such as SPE.
2120
2121	  This option enables E0PD for TTBR1 where available.
2122
2123config ARM64_AS_HAS_MTE
2124	# Initial support for MTE went in binutils 2.32.0, checked with
2125	# ".arch armv8.5-a+memtag" below. However, this was incomplete
2126	# as a late addition to the final architecture spec (LDGM/STGM)
2127	# is only supported in the newer 2.32.x and 2.33 binutils
2128	# versions, hence the extra "stgm" instruction check below.
2129	def_bool $(as-instr,.arch armv8.5-a+memtag\nstgm xzr$(comma)[x0])
2130
2131config ARM64_MTE
2132	bool "Memory Tagging Extension support"
2133	default y
2134	depends on ARM64_AS_HAS_MTE && ARM64_TAGGED_ADDR_ABI
2135	depends on AS_HAS_ARMV8_5
2136	# Required for tag checking in the uaccess routines
2137	select ARM64_PAN
2138	select ARCH_HAS_SUBPAGE_FAULTS
2139	select ARCH_USES_HIGH_VMA_FLAGS
2140	select ARCH_USES_PG_ARCH_2
2141	select ARCH_USES_PG_ARCH_3
2142	help
2143	  Memory Tagging (part of the ARMv8.5 Extensions) provides
2144	  architectural support for run-time, always-on detection of
2145	  various classes of memory error to aid with software debugging
2146	  to eliminate vulnerabilities arising from memory-unsafe
2147	  languages.
2148
2149	  This option enables the support for the Memory Tagging
2150	  Extension at EL0 (i.e. for userspace).
2151
2152	  Selecting this option allows the feature to be detected at
2153	  runtime. Any secondary CPU not implementing this feature will
2154	  not be allowed a late bring-up.
2155
2156	  Userspace binaries that want to use this feature must
2157	  explicitly opt in. The mechanism for the userspace is
2158	  described in:
2159
2160	  Documentation/arch/arm64/memory-tagging-extension.rst.
2161
2162endmenu # "ARMv8.5 architectural features"
2163
2164menu "ARMv8.7 architectural features"
2165
2166config ARM64_EPAN
2167	bool "Enable support for Enhanced Privileged Access Never (EPAN)"
2168	default y
2169	depends on ARM64_PAN
2170	help
2171	  Enhanced Privileged Access Never (EPAN) allows Privileged
2172	  Access Never to be used with Execute-only mappings.
2173
2174	  The feature is detected at runtime, and will remain disabled
2175	  if the cpu does not implement the feature.
2176endmenu # "ARMv8.7 architectural features"
2177
2178config AS_HAS_MOPS
2179	def_bool $(as-instr,.arch_extension mops)
2180
2181menu "ARMv8.9 architectural features"
2182
2183config ARM64_POE
2184	prompt "Permission Overlay Extension"
2185	def_bool y
2186	select ARCH_USES_HIGH_VMA_FLAGS
2187	select ARCH_HAS_PKEYS
2188	help
2189	  The Permission Overlay Extension is used to implement Memory
2190	  Protection Keys. Memory Protection Keys provides a mechanism for
2191	  enforcing page-based protections, but without requiring modification
2192	  of the page tables when an application changes protection domains.
2193
2194	  For details, see Documentation/core-api/protection-keys.rst
2195
2196	  If unsure, say y.
2197
2198config ARCH_PKEY_BITS
2199	int
2200	default 3
2201
2202config ARM64_HAFT
2203	bool "Support for Hardware managed Access Flag for Table Descriptors"
2204	depends on ARM64_HW_AFDBM
2205	default y
2206	help
2207	  The ARMv8.9/ARMv9.5 introduces the feature Hardware managed Access
2208	  Flag for Table descriptors. When enabled an architectural executed
2209	  memory access will update the Access Flag in each Table descriptor
2210	  which is accessed during the translation table walk and for which
2211	  the Access Flag is 0. The Access Flag of the Table descriptor use
2212	  the same bit of PTE_AF.
2213
2214	  The feature will only be enabled if all the CPUs in the system
2215	  support this feature. If unsure, say Y.
2216
2217endmenu # "ARMv8.9 architectural features"
2218
2219menu "v9.4 architectural features"
2220
2221config ARM64_GCS
2222	bool "Enable support for Guarded Control Stack (GCS)"
2223	default y
2224	select ARCH_HAS_USER_SHADOW_STACK
2225	select ARCH_USES_HIGH_VMA_FLAGS
2226	depends on !UPROBES
2227	help
2228	  Guarded Control Stack (GCS) provides support for a separate
2229	  stack with restricted access which contains only return
2230	  addresses.  This can be used to harden against some attacks
2231	  by comparing return address used by the program with what is
2232	  stored in the GCS, and may also be used to efficiently obtain
2233	  the call stack for applications such as profiling.
2234
2235	  The feature is detected at runtime, and will remain disabled
2236	  if the system does not implement the feature.
2237
2238endmenu # "v9.4 architectural features"
2239
2240config ARM64_SVE
2241	bool "ARM Scalable Vector Extension support"
2242	default y
2243	help
2244	  The Scalable Vector Extension (SVE) is an extension to the AArch64
2245	  execution state which complements and extends the SIMD functionality
2246	  of the base architecture to support much larger vectors and to enable
2247	  additional vectorisation opportunities.
2248
2249	  To enable use of this extension on CPUs that implement it, say Y.
2250
2251	  On CPUs that support the SVE2 extensions, this option will enable
2252	  those too.
2253
2254	  Note that for architectural reasons, firmware _must_ implement SVE
2255	  support when running on SVE capable hardware.  The required support
2256	  is present in:
2257
2258	    * version 1.5 and later of the ARM Trusted Firmware
2259	    * the AArch64 boot wrapper since commit 5e1261e08abf
2260	      ("bootwrapper: SVE: Enable SVE for EL2 and below").
2261
2262	  For other firmware implementations, consult the firmware documentation
2263	  or vendor.
2264
2265	  If you need the kernel to boot on SVE-capable hardware with broken
2266	  firmware, you may need to say N here until you get your firmware
2267	  fixed.  Otherwise, you may experience firmware panics or lockups when
2268	  booting the kernel.  If unsure and you are not observing these
2269	  symptoms, you should assume that it is safe to say Y.
2270
2271config ARM64_SME
2272	bool "ARM Scalable Matrix Extension support"
2273	default y
2274	depends on ARM64_SVE
2275	help
2276	  The Scalable Matrix Extension (SME) is an extension to the AArch64
2277	  execution state which utilises a substantial subset of the SVE
2278	  instruction set, together with the addition of new architectural
2279	  register state capable of holding two dimensional matrix tiles to
2280	  enable various matrix operations.
2281
2282config ARM64_PSEUDO_NMI
2283	bool "Support for NMI-like interrupts"
2284	select ARM_GIC_V3
2285	help
2286	  Adds support for mimicking Non-Maskable Interrupts through the use of
2287	  GIC interrupt priority. This support requires version 3 or later of
2288	  ARM GIC.
2289
2290	  This high priority configuration for interrupts needs to be
2291	  explicitly enabled by setting the kernel parameter
2292	  "irqchip.gicv3_pseudo_nmi" to 1.
2293
2294	  If unsure, say N
2295
2296if ARM64_PSEUDO_NMI
2297config ARM64_DEBUG_PRIORITY_MASKING
2298	bool "Debug interrupt priority masking"
2299	help
2300	  This adds runtime checks to functions enabling/disabling
2301	  interrupts when using priority masking. The additional checks verify
2302	  the validity of ICC_PMR_EL1 when calling concerned functions.
2303
2304	  If unsure, say N
2305endif # ARM64_PSEUDO_NMI
2306
2307config RELOCATABLE
2308	bool "Build a relocatable kernel image" if EXPERT
2309	select ARCH_HAS_RELR
2310	default y
2311	help
2312	  This builds the kernel as a Position Independent Executable (PIE),
2313	  which retains all relocation metadata required to relocate the
2314	  kernel binary at runtime to a different virtual address than the
2315	  address it was linked at.
2316	  Since AArch64 uses the RELA relocation format, this requires a
2317	  relocation pass at runtime even if the kernel is loaded at the
2318	  same address it was linked at.
2319
2320config RANDOMIZE_BASE
2321	bool "Randomize the address of the kernel image"
2322	select RELOCATABLE
2323	help
2324	  Randomizes the virtual address at which the kernel image is
2325	  loaded, as a security feature that deters exploit attempts
2326	  relying on knowledge of the location of kernel internals.
2327
2328	  It is the bootloader's job to provide entropy, by passing a
2329	  random u64 value in /chosen/kaslr-seed at kernel entry.
2330
2331	  When booting via the UEFI stub, it will invoke the firmware's
2332	  EFI_RNG_PROTOCOL implementation (if available) to supply entropy
2333	  to the kernel proper. In addition, it will randomise the physical
2334	  location of the kernel Image as well.
2335
2336	  If unsure, say N.
2337
2338config RANDOMIZE_MODULE_REGION_FULL
2339	bool "Randomize the module region over a 2 GB range"
2340	depends on RANDOMIZE_BASE
2341	default y
2342	help
2343	  Randomizes the location of the module region inside a 2 GB window
2344	  covering the core kernel. This way, it is less likely for modules
2345	  to leak information about the location of core kernel data structures
2346	  but it does imply that function calls between modules and the core
2347	  kernel will need to be resolved via veneers in the module PLT.
2348
2349	  When this option is not set, the module region will be randomized over
2350	  a limited range that contains the [_stext, _etext] interval of the
2351	  core kernel, so branch relocations are almost always in range unless
2352	  the region is exhausted. In this particular case of region
2353	  exhaustion, modules might be able to fall back to a larger 2GB area.
2354
2355config CC_HAVE_STACKPROTECTOR_SYSREG
2356	def_bool $(cc-option,-mstack-protector-guard=sysreg -mstack-protector-guard-reg=sp_el0 -mstack-protector-guard-offset=0)
2357
2358config STACKPROTECTOR_PER_TASK
2359	def_bool y
2360	depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_SYSREG
2361
2362config UNWIND_PATCH_PAC_INTO_SCS
2363	bool "Enable shadow call stack dynamically using code patching"
2364	# needs Clang with https://github.com/llvm/llvm-project/commit/de07cde67b5d205d58690be012106022aea6d2b3 incorporated
2365	depends on CC_IS_CLANG && CLANG_VERSION >= 150000
2366	depends on ARM64_PTR_AUTH_KERNEL && CC_HAS_BRANCH_PROT_PAC_RET
2367	depends on SHADOW_CALL_STACK
2368	select UNWIND_TABLES
2369	select DYNAMIC_SCS
2370
2371config ARM64_CONTPTE
2372	bool "Contiguous PTE mappings for user memory" if EXPERT
2373	depends on TRANSPARENT_HUGEPAGE
2374	default y
2375	help
2376	  When enabled, user mappings are configured using the PTE contiguous
2377	  bit, for any mappings that meet the size and alignment requirements.
2378	  This reduces TLB pressure and improves performance.
2379
2380endmenu # "Kernel Features"
2381
2382menu "Boot options"
2383
2384config ARM64_ACPI_PARKING_PROTOCOL
2385	bool "Enable support for the ARM64 ACPI parking protocol"
2386	depends on ACPI
2387	help
2388	  Enable support for the ARM64 ACPI parking protocol. If disabled
2389	  the kernel will not allow booting through the ARM64 ACPI parking
2390	  protocol even if the corresponding data is present in the ACPI
2391	  MADT table.
2392
2393config CMDLINE
2394	string "Default kernel command string"
2395	default ""
2396	help
2397	  Provide a set of default command-line options at build time by
2398	  entering them here. As a minimum, you should specify the the
2399	  root device (e.g. root=/dev/nfs).
2400
2401choice
2402	prompt "Kernel command line type"
2403	depends on CMDLINE != ""
2404	default CMDLINE_FROM_BOOTLOADER
2405	help
2406	  Choose how the kernel will handle the provided default kernel
2407	  command line string.
2408
2409config CMDLINE_FROM_BOOTLOADER
2410	bool "Use bootloader kernel arguments if available"
2411	help
2412	  Uses the command-line options passed by the boot loader. If
2413	  the boot loader doesn't provide any, the default kernel command
2414	  string provided in CMDLINE will be used.
2415
2416config CMDLINE_FORCE
2417	bool "Always use the default kernel command string"
2418	help
2419	  Always use the default kernel command string, even if the boot
2420	  loader passes other arguments to the kernel.
2421	  This is useful if you cannot or don't want to change the
2422	  command-line options your boot loader passes to the kernel.
2423
2424endchoice
2425
2426config EFI_STUB
2427	bool
2428
2429config EFI
2430	bool "UEFI runtime support"
2431	depends on OF && !CPU_BIG_ENDIAN
2432	depends on KERNEL_MODE_NEON
2433	select ARCH_SUPPORTS_ACPI
2434	select LIBFDT
2435	select UCS2_STRING
2436	select EFI_PARAMS_FROM_FDT
2437	select EFI_RUNTIME_WRAPPERS
2438	select EFI_STUB
2439	select EFI_GENERIC_STUB
2440	imply IMA_SECURE_AND_OR_TRUSTED_BOOT
2441	default y
2442	help
2443	  This option provides support for runtime services provided
2444	  by UEFI firmware (such as non-volatile variables, realtime
2445	  clock, and platform reset). A UEFI stub is also provided to
2446	  allow the kernel to be booted as an EFI application. This
2447	  is only useful on systems that have UEFI firmware.
2448
2449config COMPRESSED_INSTALL
2450	bool "Install compressed image by default"
2451	help
2452	  This makes the regular "make install" install the compressed
2453	  image we built, not the legacy uncompressed one.
2454
2455	  You can check that a compressed image works for you by doing
2456	  "make zinstall" first, and verifying that everything is fine
2457	  in your environment before making "make install" do this for
2458	  you.
2459
2460config DMI
2461	bool "Enable support for SMBIOS (DMI) tables"
2462	depends on EFI
2463	default y
2464	help
2465	  This enables SMBIOS/DMI feature for systems.
2466
2467	  This option is only useful on systems that have UEFI firmware.
2468	  However, even with this option, the resultant kernel should
2469	  continue to boot on existing non-UEFI platforms.
2470
2471endmenu # "Boot options"
2472
2473menu "Power management options"
2474
2475source "kernel/power/Kconfig"
2476
2477config ARCH_HIBERNATION_POSSIBLE
2478	def_bool y
2479	depends on CPU_PM
2480
2481config ARCH_HIBERNATION_HEADER
2482	def_bool y
2483	depends on HIBERNATION
2484
2485config ARCH_SUSPEND_POSSIBLE
2486	def_bool y
2487
2488endmenu # "Power management options"
2489
2490menu "CPU Power Management"
2491
2492source "drivers/cpuidle/Kconfig"
2493
2494source "drivers/cpufreq/Kconfig"
2495
2496endmenu # "CPU Power Management"
2497
2498source "drivers/acpi/Kconfig"
2499
2500source "arch/arm64/kvm/Kconfig"
2501
2502