xref: /linux/arch/arm64/Kconfig (revision 8530ea3c9b9747faba46ed3a59ad103b894f1189)
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_PTDUMP
46	select ARCH_HAS_PTE_DEVMAP
47	select ARCH_HAS_PTE_SPECIAL
48	select ARCH_HAS_HW_PTE_YOUNG
49	select ARCH_HAS_SETUP_DMA_OPS
50	select ARCH_HAS_SET_DIRECT_MAP
51	select ARCH_HAS_SET_MEMORY
52	select ARCH_HAS_MEM_ENCRYPT
53	select ARCH_HAS_FORCE_DMA_UNENCRYPTED
54	select ARCH_STACKWALK
55	select ARCH_HAS_STRICT_KERNEL_RWX
56	select ARCH_HAS_STRICT_MODULE_RWX
57	select ARCH_HAS_SYNC_DMA_FOR_DEVICE
58	select ARCH_HAS_SYNC_DMA_FOR_CPU
59	select ARCH_HAS_SYSCALL_WRAPPER
60	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
61	select ARCH_HAS_ZONE_DMA_SET if EXPERT
62	select ARCH_HAVE_ELF_PROT
63	select ARCH_HAVE_NMI_SAFE_CMPXCHG
64	select ARCH_HAVE_TRACE_MMIO_ACCESS
65	select ARCH_INLINE_READ_LOCK if !PREEMPTION
66	select ARCH_INLINE_READ_LOCK_BH if !PREEMPTION
67	select ARCH_INLINE_READ_LOCK_IRQ if !PREEMPTION
68	select ARCH_INLINE_READ_LOCK_IRQSAVE if !PREEMPTION
69	select ARCH_INLINE_READ_UNLOCK if !PREEMPTION
70	select ARCH_INLINE_READ_UNLOCK_BH if !PREEMPTION
71	select ARCH_INLINE_READ_UNLOCK_IRQ if !PREEMPTION
72	select ARCH_INLINE_READ_UNLOCK_IRQRESTORE if !PREEMPTION
73	select ARCH_INLINE_WRITE_LOCK if !PREEMPTION
74	select ARCH_INLINE_WRITE_LOCK_BH if !PREEMPTION
75	select ARCH_INLINE_WRITE_LOCK_IRQ if !PREEMPTION
76	select ARCH_INLINE_WRITE_LOCK_IRQSAVE if !PREEMPTION
77	select ARCH_INLINE_WRITE_UNLOCK if !PREEMPTION
78	select ARCH_INLINE_WRITE_UNLOCK_BH if !PREEMPTION
79	select ARCH_INLINE_WRITE_UNLOCK_IRQ if !PREEMPTION
80	select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE if !PREEMPTION
81	select ARCH_INLINE_SPIN_TRYLOCK if !PREEMPTION
82	select ARCH_INLINE_SPIN_TRYLOCK_BH if !PREEMPTION
83	select ARCH_INLINE_SPIN_LOCK if !PREEMPTION
84	select ARCH_INLINE_SPIN_LOCK_BH if !PREEMPTION
85	select ARCH_INLINE_SPIN_LOCK_IRQ if !PREEMPTION
86	select ARCH_INLINE_SPIN_LOCK_IRQSAVE if !PREEMPTION
87	select ARCH_INLINE_SPIN_UNLOCK if !PREEMPTION
88	select ARCH_INLINE_SPIN_UNLOCK_BH if !PREEMPTION
89	select ARCH_INLINE_SPIN_UNLOCK_IRQ if !PREEMPTION
90	select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE if !PREEMPTION
91	select ARCH_KEEP_MEMBLOCK
92	select ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE
93	select ARCH_USE_CMPXCHG_LOCKREF
94	select ARCH_USE_GNU_PROPERTY
95	select ARCH_USE_MEMTEST
96	select ARCH_USE_QUEUED_RWLOCKS
97	select ARCH_USE_QUEUED_SPINLOCKS
98	select ARCH_USE_SYM_ANNOTATIONS
99	select ARCH_SUPPORTS_DEBUG_PAGEALLOC
100	select ARCH_SUPPORTS_HUGETLBFS
101	select ARCH_SUPPORTS_MEMORY_FAILURE
102	select ARCH_SUPPORTS_SHADOW_CALL_STACK if CC_HAVE_SHADOW_CALL_STACK
103	select ARCH_SUPPORTS_LTO_CLANG if CPU_LITTLE_ENDIAN
104	select ARCH_SUPPORTS_LTO_CLANG_THIN
105	select ARCH_SUPPORTS_CFI_CLANG
106	select ARCH_SUPPORTS_ATOMIC_RMW
107	select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
108	select ARCH_SUPPORTS_NUMA_BALANCING
109	select ARCH_SUPPORTS_PAGE_TABLE_CHECK
110	select ARCH_SUPPORTS_PER_VMA_LOCK
111	select ARCH_SUPPORTS_HUGE_PFNMAP if TRANSPARENT_HUGEPAGE
112	select ARCH_SUPPORTS_RT
113	select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
114	select ARCH_WANT_COMPAT_IPC_PARSE_VERSION if COMPAT
115	select ARCH_WANT_DEFAULT_BPF_JIT
116	select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT
117	select ARCH_WANT_FRAME_POINTERS
118	select ARCH_WANT_HUGE_PMD_SHARE if ARM64_4K_PAGES || (ARM64_16K_PAGES && !ARM64_VA_BITS_36)
119	select ARCH_WANT_LD_ORPHAN_WARN
120	select ARCH_WANTS_EXECMEM_LATE
121	select ARCH_WANTS_NO_INSTR
122	select ARCH_WANTS_THP_SWAP if ARM64_4K_PAGES
123	select ARCH_HAS_UBSAN
124	select ARM_AMBA
125	select ARM_ARCH_TIMER
126	select ARM_GIC
127	select AUDIT_ARCH_COMPAT_GENERIC
128	select ARM_GIC_V2M if PCI
129	select ARM_GIC_V3
130	select ARM_GIC_V3_ITS if PCI
131	select ARM_PSCI_FW
132	select BUILDTIME_TABLE_SORT
133	select CLONE_BACKWARDS
134	select COMMON_CLK
135	select CPU_PM if (SUSPEND || CPU_IDLE)
136	select CPUMASK_OFFSTACK if NR_CPUS > 256
137	select CRC32
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_64K_PAGES
337	default 31 if ARM64_VA_BITS=48 && ARM64_16K_PAGES
338	default 33 if ARM64_VA_BITS=48
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 ARM64_WORKAROUND_CLEAN_CACHE
468	bool
469
470config ARM64_ERRATUM_826319
471	bool "Cortex-A53: 826319: System might deadlock if a write cannot complete until read data is accepted"
472	default y
473	select ARM64_WORKAROUND_CLEAN_CACHE
474	help
475	  This option adds an alternative code sequence to work around ARM
476	  erratum 826319 on Cortex-A53 parts up to r0p2 with an AMBA 4 ACE or
477	  AXI master interface and an L2 cache.
478
479	  If a Cortex-A53 uses an AMBA AXI4 ACE interface to other processors
480	  and is unable to accept a certain write via this interface, it will
481	  not progress on read data presented on the read data channel and the
482	  system can deadlock.
483
484	  The workaround promotes data cache clean instructions to
485	  data cache clean-and-invalidate.
486	  Please note that this does not necessarily enable the workaround,
487	  as it depends on the alternative framework, which will only patch
488	  the kernel if an affected CPU is detected.
489
490	  If unsure, say Y.
491
492config ARM64_ERRATUM_827319
493	bool "Cortex-A53: 827319: Data cache clean instructions might cause overlapping transactions to the interconnect"
494	default y
495	select ARM64_WORKAROUND_CLEAN_CACHE
496	help
497	  This option adds an alternative code sequence to work around ARM
498	  erratum 827319 on Cortex-A53 parts up to r0p2 with an AMBA 5 CHI
499	  master interface and an L2 cache.
500
501	  Under certain conditions this erratum can cause a clean line eviction
502	  to occur at the same time as another transaction to the same address
503	  on the AMBA 5 CHI interface, which can cause data corruption if the
504	  interconnect reorders the two transactions.
505
506	  The workaround promotes data cache clean instructions to
507	  data cache clean-and-invalidate.
508	  Please note that this does not necessarily enable the workaround,
509	  as it depends on the alternative framework, which will only patch
510	  the kernel if an affected CPU is detected.
511
512	  If unsure, say Y.
513
514config ARM64_ERRATUM_824069
515	bool "Cortex-A53: 824069: Cache line might not be marked as clean after a CleanShared snoop"
516	default y
517	select ARM64_WORKAROUND_CLEAN_CACHE
518	help
519	  This option adds an alternative code sequence to work around ARM
520	  erratum 824069 on Cortex-A53 parts up to r0p2 when it is connected
521	  to a coherent interconnect.
522
523	  If a Cortex-A53 processor is executing a store or prefetch for
524	  write instruction at the same time as a processor in another
525	  cluster is executing a cache maintenance operation to the same
526	  address, then this erratum might cause a clean cache line to be
527	  incorrectly marked as dirty.
528
529	  The workaround promotes data cache clean instructions to
530	  data cache clean-and-invalidate.
531	  Please note that this option does not necessarily enable the
532	  workaround, as it depends on the alternative framework, which will
533	  only patch the kernel if an affected CPU is detected.
534
535	  If unsure, say Y.
536
537config ARM64_ERRATUM_819472
538	bool "Cortex-A53: 819472: Store exclusive instructions might cause data corruption"
539	default y
540	select ARM64_WORKAROUND_CLEAN_CACHE
541	help
542	  This option adds an alternative code sequence to work around ARM
543	  erratum 819472 on Cortex-A53 parts up to r0p1 with an L2 cache
544	  present when it is connected to a coherent interconnect.
545
546	  If the processor is executing a load and store exclusive sequence at
547	  the same time as a processor in another cluster is executing a cache
548	  maintenance operation to the same address, then this erratum might
549	  cause data corruption.
550
551	  The workaround promotes data cache clean instructions to
552	  data cache clean-and-invalidate.
553	  Please note that this does not necessarily enable the workaround,
554	  as it depends on the alternative framework, which will only patch
555	  the kernel if an affected CPU is detected.
556
557	  If unsure, say Y.
558
559config ARM64_ERRATUM_832075
560	bool "Cortex-A57: 832075: possible deadlock on mixing exclusive memory accesses with device loads"
561	default y
562	help
563	  This option adds an alternative code sequence to work around ARM
564	  erratum 832075 on Cortex-A57 parts up to r1p2.
565
566	  Affected Cortex-A57 parts might deadlock when exclusive load/store
567	  instructions to Write-Back memory are mixed with Device loads.
568
569	  The workaround is to promote device loads to use Load-Acquire
570	  semantics.
571	  Please note that this does not necessarily enable the workaround,
572	  as it depends on the alternative framework, which will only patch
573	  the kernel if an affected CPU is detected.
574
575	  If unsure, say Y.
576
577config ARM64_ERRATUM_834220
578	bool "Cortex-A57: 834220: Stage 2 translation fault might be incorrectly reported in presence of a Stage 1 fault (rare)"
579	depends on KVM
580	help
581	  This option adds an alternative code sequence to work around ARM
582	  erratum 834220 on Cortex-A57 parts up to r1p2.
583
584	  Affected Cortex-A57 parts might report a Stage 2 translation
585	  fault as the result of a Stage 1 fault for load crossing a
586	  page boundary when there is a permission or device memory
587	  alignment fault at Stage 1 and a translation fault at Stage 2.
588
589	  The workaround is to verify that the Stage 1 translation
590	  doesn't generate a fault before handling the Stage 2 fault.
591	  Please note that this does not necessarily enable the workaround,
592	  as it depends on the alternative framework, which will only patch
593	  the kernel if an affected CPU is detected.
594
595	  If unsure, say N.
596
597config ARM64_ERRATUM_1742098
598	bool "Cortex-A57/A72: 1742098: ELR recorded incorrectly on interrupt taken between cryptographic instructions in a sequence"
599	depends on COMPAT
600	default y
601	help
602	  This option removes the AES hwcap for aarch32 user-space to
603	  workaround erratum 1742098 on Cortex-A57 and Cortex-A72.
604
605	  Affected parts may corrupt the AES state if an interrupt is
606	  taken between a pair of AES instructions. These instructions
607	  are only present if the cryptography extensions are present.
608	  All software should have a fallback implementation for CPUs
609	  that don't implement the cryptography extensions.
610
611	  If unsure, say Y.
612
613config ARM64_ERRATUM_845719
614	bool "Cortex-A53: 845719: a load might read incorrect data"
615	depends on COMPAT
616	default y
617	help
618	  This option adds an alternative code sequence to work around ARM
619	  erratum 845719 on Cortex-A53 parts up to r0p4.
620
621	  When running a compat (AArch32) userspace on an affected Cortex-A53
622	  part, a load at EL0 from a virtual address that matches the bottom 32
623	  bits of the virtual address used by a recent load at (AArch64) EL1
624	  might return incorrect data.
625
626	  The workaround is to write the contextidr_el1 register on exception
627	  return to a 32-bit task.
628	  Please note that this does not necessarily enable the workaround,
629	  as it depends on the alternative framework, which will only patch
630	  the kernel if an affected CPU is detected.
631
632	  If unsure, say Y.
633
634config ARM64_ERRATUM_843419
635	bool "Cortex-A53: 843419: A load or store might access an incorrect address"
636	default y
637	help
638	  This option links the kernel with '--fix-cortex-a53-843419' and
639	  enables PLT support to replace certain ADRP instructions, which can
640	  cause subsequent memory accesses to use an incorrect address on
641	  Cortex-A53 parts up to r0p4.
642
643	  If unsure, say Y.
644
645config ARM64_ERRATUM_1024718
646	bool "Cortex-A55: 1024718: Update of DBM/AP bits without break before make might result in incorrect update"
647	default y
648	help
649	  This option adds a workaround for ARM Cortex-A55 Erratum 1024718.
650
651	  Affected Cortex-A55 cores (all revisions) could cause incorrect
652	  update of the hardware dirty bit when the DBM/AP bits are updated
653	  without a break-before-make. The workaround is to disable the usage
654	  of hardware DBM locally on the affected cores. CPUs not affected by
655	  this erratum will continue to use the feature.
656
657	  If unsure, say Y.
658
659config ARM64_ERRATUM_1418040
660	bool "Cortex-A76/Neoverse-N1: MRC read following MRRC read of specific Generic Timer in AArch32 might give incorrect result"
661	default y
662	depends on COMPAT
663	help
664	  This option adds a workaround for ARM Cortex-A76/Neoverse-N1
665	  errata 1188873 and 1418040.
666
667	  Affected Cortex-A76/Neoverse-N1 cores (r0p0 to r3p1) could
668	  cause register corruption when accessing the timer registers
669	  from AArch32 userspace.
670
671	  If unsure, say Y.
672
673config ARM64_WORKAROUND_SPECULATIVE_AT
674	bool
675
676config ARM64_ERRATUM_1165522
677	bool "Cortex-A76: 1165522: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
678	default y
679	select ARM64_WORKAROUND_SPECULATIVE_AT
680	help
681	  This option adds a workaround for ARM Cortex-A76 erratum 1165522.
682
683	  Affected Cortex-A76 cores (r0p0, r1p0, r2p0) could end-up with
684	  corrupted TLBs by speculating an AT instruction during a guest
685	  context switch.
686
687	  If unsure, say Y.
688
689config ARM64_ERRATUM_1319367
690	bool "Cortex-A57/A72: 1319537: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
691	default y
692	select ARM64_WORKAROUND_SPECULATIVE_AT
693	help
694	  This option adds work arounds for ARM Cortex-A57 erratum 1319537
695	  and A72 erratum 1319367
696
697	  Cortex-A57 and A72 cores could end-up with corrupted TLBs by
698	  speculating an AT instruction during a guest context switch.
699
700	  If unsure, say Y.
701
702config ARM64_ERRATUM_1530923
703	bool "Cortex-A55: 1530923: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
704	default y
705	select ARM64_WORKAROUND_SPECULATIVE_AT
706	help
707	  This option adds a workaround for ARM Cortex-A55 erratum 1530923.
708
709	  Affected Cortex-A55 cores (r0p0, r0p1, r1p0, r2p0) could end-up with
710	  corrupted TLBs by speculating an AT instruction during a guest
711	  context switch.
712
713	  If unsure, say Y.
714
715config ARM64_WORKAROUND_REPEAT_TLBI
716	bool
717
718config ARM64_ERRATUM_2441007
719	bool "Cortex-A55: Completion of affected memory accesses might not be guaranteed by completion of a TLBI (rare)"
720	select ARM64_WORKAROUND_REPEAT_TLBI
721	help
722	  This option adds a workaround for ARM Cortex-A55 erratum #2441007.
723
724	  Under very rare circumstances, affected Cortex-A55 CPUs
725	  may not handle a race between a break-before-make sequence on one
726	  CPU, and another CPU accessing the same page. This could allow a
727	  store to a page that has been unmapped.
728
729	  Work around this by adding the affected CPUs to the list that needs
730	  TLB sequences to be done twice.
731
732	  If unsure, say N.
733
734config ARM64_ERRATUM_1286807
735	bool "Cortex-A76: Modification of the translation table for a virtual address might lead to read-after-read ordering violation (rare)"
736	select ARM64_WORKAROUND_REPEAT_TLBI
737	help
738	  This option adds a workaround for ARM Cortex-A76 erratum 1286807.
739
740	  On the affected Cortex-A76 cores (r0p0 to r3p0), if a virtual
741	  address for a cacheable mapping of a location is being
742	  accessed by a core while another core is remapping the virtual
743	  address to a new physical page using the recommended
744	  break-before-make sequence, then under very rare circumstances
745	  TLBI+DSB completes before a read using the translation being
746	  invalidated has been observed by other observers. The
747	  workaround repeats the TLBI+DSB operation.
748
749	  If unsure, say N.
750
751config ARM64_ERRATUM_1463225
752	bool "Cortex-A76: Software Step might prevent interrupt recognition"
753	default y
754	help
755	  This option adds a workaround for Arm Cortex-A76 erratum 1463225.
756
757	  On the affected Cortex-A76 cores (r0p0 to r3p1), software stepping
758	  of a system call instruction (SVC) can prevent recognition of
759	  subsequent interrupts when software stepping is disabled in the
760	  exception handler of the system call and either kernel debugging
761	  is enabled or VHE is in use.
762
763	  Work around the erratum by triggering a dummy step exception
764	  when handling a system call from a task that is being stepped
765	  in a VHE configuration of the kernel.
766
767	  If unsure, say Y.
768
769config ARM64_ERRATUM_1542419
770	bool "Neoverse-N1: workaround mis-ordering of instruction fetches (rare)"
771	help
772	  This option adds a workaround for ARM Neoverse-N1 erratum
773	  1542419.
774
775	  Affected Neoverse-N1 cores could execute a stale instruction when
776	  modified by another CPU. The workaround depends on a firmware
777	  counterpart.
778
779	  Workaround the issue by hiding the DIC feature from EL0. This
780	  forces user-space to perform cache maintenance.
781
782	  If unsure, say N.
783
784config ARM64_ERRATUM_1508412
785	bool "Cortex-A77: 1508412: workaround deadlock on sequence of NC/Device load and store exclusive or PAR read"
786	default y
787	help
788	  This option adds a workaround for Arm Cortex-A77 erratum 1508412.
789
790	  Affected Cortex-A77 cores (r0p0, r1p0) could deadlock on a sequence
791	  of a store-exclusive or read of PAR_EL1 and a load with device or
792	  non-cacheable memory attributes. The workaround depends on a firmware
793	  counterpart.
794
795	  KVM guests must also have the workaround implemented or they can
796	  deadlock the system.
797
798	  Work around the issue by inserting DMB SY barriers around PAR_EL1
799	  register reads and warning KVM users. The DMB barrier is sufficient
800	  to prevent a speculative PAR_EL1 read.
801
802	  If unsure, say Y.
803
804config ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
805	bool
806
807config ARM64_ERRATUM_2051678
808	bool "Cortex-A510: 2051678: disable Hardware Update of the page table dirty bit"
809	default y
810	help
811	  This options adds the workaround for ARM Cortex-A510 erratum ARM64_ERRATUM_2051678.
812	  Affected Cortex-A510 might not respect the ordering rules for
813	  hardware update of the page table's dirty bit. The workaround
814	  is to not enable the feature on affected CPUs.
815
816	  If unsure, say Y.
817
818config ARM64_ERRATUM_2077057
819	bool "Cortex-A510: 2077057: workaround software-step corrupting SPSR_EL2"
820	default y
821	help
822	  This option adds the workaround for ARM Cortex-A510 erratum 2077057.
823	  Affected Cortex-A510 may corrupt SPSR_EL2 when the a step exception is
824	  expected, but a Pointer Authentication trap is taken instead. The
825	  erratum causes SPSR_EL1 to be copied to SPSR_EL2, which could allow
826	  EL1 to cause a return to EL2 with a guest controlled ELR_EL2.
827
828	  This can only happen when EL2 is stepping EL1.
829
830	  When these conditions occur, the SPSR_EL2 value is unchanged from the
831	  previous guest entry, and can be restored from the in-memory copy.
832
833	  If unsure, say Y.
834
835config ARM64_ERRATUM_2658417
836	bool "Cortex-A510: 2658417: remove BF16 support due to incorrect result"
837	default y
838	help
839	  This option adds the workaround for ARM Cortex-A510 erratum 2658417.
840	  Affected Cortex-A510 (r0p0 to r1p1) may produce the wrong result for
841	  BFMMLA or VMMLA instructions in rare circumstances when a pair of
842	  A510 CPUs are using shared neon hardware. As the sharing is not
843	  discoverable by the kernel, hide the BF16 HWCAP to indicate that
844	  user-space should not be using these instructions.
845
846	  If unsure, say Y.
847
848config ARM64_ERRATUM_2119858
849	bool "Cortex-A710/X2: 2119858: workaround TRBE overwriting trace data in FILL mode"
850	default y
851	depends on CORESIGHT_TRBE
852	select ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
853	help
854	  This option adds the workaround for ARM Cortex-A710/X2 erratum 2119858.
855
856	  Affected Cortex-A710/X2 cores could overwrite up to 3 cache lines of trace
857	  data at the base of the buffer (pointed to by TRBASER_EL1) in FILL mode in
858	  the event of a WRAP event.
859
860	  Work around the issue by always making sure we move the TRBPTR_EL1 by
861	  256 bytes before enabling the buffer and filling the first 256 bytes of
862	  the buffer with ETM ignore packets upon disabling.
863
864	  If unsure, say Y.
865
866config ARM64_ERRATUM_2139208
867	bool "Neoverse-N2: 2139208: workaround TRBE overwriting trace data in FILL mode"
868	default y
869	depends on CORESIGHT_TRBE
870	select ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
871	help
872	  This option adds the workaround for ARM Neoverse-N2 erratum 2139208.
873
874	  Affected Neoverse-N2 cores could overwrite up to 3 cache lines of trace
875	  data at the base of the buffer (pointed to by TRBASER_EL1) in FILL mode in
876	  the event of a WRAP event.
877
878	  Work around the issue by always making sure we move the TRBPTR_EL1 by
879	  256 bytes before enabling the buffer and filling the first 256 bytes of
880	  the buffer with ETM ignore packets upon disabling.
881
882	  If unsure, say Y.
883
884config ARM64_WORKAROUND_TSB_FLUSH_FAILURE
885	bool
886
887config ARM64_ERRATUM_2054223
888	bool "Cortex-A710: 2054223: workaround TSB instruction failing to flush trace"
889	default y
890	select ARM64_WORKAROUND_TSB_FLUSH_FAILURE
891	help
892	  Enable workaround for ARM Cortex-A710 erratum 2054223
893
894	  Affected cores may fail to flush the trace data on a TSB instruction, when
895	  the PE is in trace prohibited state. This will cause losing a few bytes
896	  of the trace cached.
897
898	  Workaround is to issue two TSB consecutively on affected cores.
899
900	  If unsure, say Y.
901
902config ARM64_ERRATUM_2067961
903	bool "Neoverse-N2: 2067961: workaround TSB instruction failing to flush trace"
904	default y
905	select ARM64_WORKAROUND_TSB_FLUSH_FAILURE
906	help
907	  Enable workaround for ARM Neoverse-N2 erratum 2067961
908
909	  Affected cores may fail to flush the trace data on a TSB instruction, when
910	  the PE is in trace prohibited state. This will cause losing a few bytes
911	  of the trace cached.
912
913	  Workaround is to issue two TSB consecutively on affected cores.
914
915	  If unsure, say Y.
916
917config ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE
918	bool
919
920config ARM64_ERRATUM_2253138
921	bool "Neoverse-N2: 2253138: workaround TRBE writing to address out-of-range"
922	depends on CORESIGHT_TRBE
923	default y
924	select ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE
925	help
926	  This option adds the workaround for ARM Neoverse-N2 erratum 2253138.
927
928	  Affected Neoverse-N2 cores might write to an out-of-range address, not reserved
929	  for TRBE. Under some conditions, the TRBE might generate a write to the next
930	  virtually addressed page following the last page of the TRBE address space
931	  (i.e., the TRBLIMITR_EL1.LIMIT), instead of wrapping around to the base.
932
933	  Work around this in the driver by always making sure that there is a
934	  page beyond the TRBLIMITR_EL1.LIMIT, within the space allowed for the TRBE.
935
936	  If unsure, say Y.
937
938config ARM64_ERRATUM_2224489
939	bool "Cortex-A710/X2: 2224489: workaround TRBE writing to address out-of-range"
940	depends on CORESIGHT_TRBE
941	default y
942	select ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE
943	help
944	  This option adds the workaround for ARM Cortex-A710/X2 erratum 2224489.
945
946	  Affected Cortex-A710/X2 cores might write to an out-of-range address, not reserved
947	  for TRBE. Under some conditions, the TRBE might generate a write to the next
948	  virtually addressed page following the last page of the TRBE address space
949	  (i.e., the TRBLIMITR_EL1.LIMIT), instead of wrapping around to the base.
950
951	  Work around this in the driver by always making sure that there is a
952	  page beyond the TRBLIMITR_EL1.LIMIT, within the space allowed for the TRBE.
953
954	  If unsure, say Y.
955
956config ARM64_ERRATUM_2441009
957	bool "Cortex-A510: Completion of affected memory accesses might not be guaranteed by completion of a TLBI (rare)"
958	select ARM64_WORKAROUND_REPEAT_TLBI
959	help
960	  This option adds a workaround for ARM Cortex-A510 erratum #2441009.
961
962	  Under very rare circumstances, affected Cortex-A510 CPUs
963	  may not handle a race between a break-before-make sequence on one
964	  CPU, and another CPU accessing the same page. This could allow a
965	  store to a page that has been unmapped.
966
967	  Work around this by adding the affected CPUs to the list that needs
968	  TLB sequences to be done twice.
969
970	  If unsure, say N.
971
972config ARM64_ERRATUM_2064142
973	bool "Cortex-A510: 2064142: workaround TRBE register writes while disabled"
974	depends on CORESIGHT_TRBE
975	default y
976	help
977	  This option adds the workaround for ARM Cortex-A510 erratum 2064142.
978
979	  Affected Cortex-A510 core might fail to write into system registers after the
980	  TRBE has been disabled. Under some conditions after the TRBE has been disabled
981	  writes into TRBE registers TRBLIMITR_EL1, TRBPTR_EL1, TRBBASER_EL1, TRBSR_EL1,
982	  and TRBTRG_EL1 will be ignored and will not be effected.
983
984	  Work around this in the driver by executing TSB CSYNC and DSB after collection
985	  is stopped and before performing a system register write to one of the affected
986	  registers.
987
988	  If unsure, say Y.
989
990config ARM64_ERRATUM_2038923
991	bool "Cortex-A510: 2038923: workaround TRBE corruption with enable"
992	depends on CORESIGHT_TRBE
993	default y
994	help
995	  This option adds the workaround for ARM Cortex-A510 erratum 2038923.
996
997	  Affected Cortex-A510 core might cause an inconsistent view on whether trace is
998	  prohibited within the CPU. As a result, the trace buffer or trace buffer state
999	  might be corrupted. This happens after TRBE buffer has been enabled by setting
1000	  TRBLIMITR_EL1.E, followed by just a single context synchronization event before
1001	  execution changes from a context, in which trace is prohibited to one where it
1002	  isn't, or vice versa. In these mentioned conditions, the view of whether trace
1003	  is prohibited is inconsistent between parts of the CPU, and the trace buffer or
1004	  the trace buffer state might be corrupted.
1005
1006	  Work around this in the driver by preventing an inconsistent view of whether the
1007	  trace is prohibited or not based on TRBLIMITR_EL1.E by immediately following a
1008	  change to TRBLIMITR_EL1.E with at least one ISB instruction before an ERET, or
1009	  two ISB instructions if no ERET is to take place.
1010
1011	  If unsure, say Y.
1012
1013config ARM64_ERRATUM_1902691
1014	bool "Cortex-A510: 1902691: workaround TRBE trace corruption"
1015	depends on CORESIGHT_TRBE
1016	default y
1017	help
1018	  This option adds the workaround for ARM Cortex-A510 erratum 1902691.
1019
1020	  Affected Cortex-A510 core might cause trace data corruption, when being written
1021	  into the memory. Effectively TRBE is broken and hence cannot be used to capture
1022	  trace data.
1023
1024	  Work around this problem in the driver by just preventing TRBE initialization on
1025	  affected cpus. The firmware must have disabled the access to TRBE for the kernel
1026	  on such implementations. This will cover the kernel for any firmware that doesn't
1027	  do this already.
1028
1029	  If unsure, say Y.
1030
1031config ARM64_ERRATUM_2457168
1032	bool "Cortex-A510: 2457168: workaround for AMEVCNTR01 incrementing incorrectly"
1033	depends on ARM64_AMU_EXTN
1034	default y
1035	help
1036	  This option adds the workaround for ARM Cortex-A510 erratum 2457168.
1037
1038	  The AMU counter AMEVCNTR01 (constant counter) should increment at the same rate
1039	  as the system counter. On affected Cortex-A510 cores AMEVCNTR01 increments
1040	  incorrectly giving a significantly higher output value.
1041
1042	  Work around this problem by returning 0 when reading the affected counter in
1043	  key locations that results in disabling all users of this counter. This effect
1044	  is the same to firmware disabling affected counters.
1045
1046	  If unsure, say Y.
1047
1048config ARM64_ERRATUM_2645198
1049	bool "Cortex-A715: 2645198: Workaround possible [ESR|FAR]_ELx corruption"
1050	default y
1051	help
1052	  This option adds the workaround for ARM Cortex-A715 erratum 2645198.
1053
1054	  If a Cortex-A715 cpu sees a page mapping permissions change from executable
1055	  to non-executable, it may corrupt the ESR_ELx and FAR_ELx registers on the
1056	  next instruction abort caused by permission fault.
1057
1058	  Only user-space does executable to non-executable permission transition via
1059	  mprotect() system call. Workaround the problem by doing a break-before-make
1060	  TLB invalidation, for all changes to executable user space mappings.
1061
1062	  If unsure, say Y.
1063
1064config ARM64_WORKAROUND_SPECULATIVE_UNPRIV_LOAD
1065	bool
1066
1067config ARM64_ERRATUM_2966298
1068	bool "Cortex-A520: 2966298: workaround for speculatively executed unprivileged load"
1069	select ARM64_WORKAROUND_SPECULATIVE_UNPRIV_LOAD
1070	default y
1071	help
1072	  This option adds the workaround for ARM Cortex-A520 erratum 2966298.
1073
1074	  On an affected Cortex-A520 core, a speculatively executed unprivileged
1075	  load might leak data from a privileged level via a cache side channel.
1076
1077	  Work around this problem by executing a TLBI before returning to EL0.
1078
1079	  If unsure, say Y.
1080
1081config ARM64_ERRATUM_3117295
1082	bool "Cortex-A510: 3117295: workaround for speculatively executed unprivileged load"
1083	select ARM64_WORKAROUND_SPECULATIVE_UNPRIV_LOAD
1084	default y
1085	help
1086	  This option adds the workaround for ARM Cortex-A510 erratum 3117295.
1087
1088	  On an affected Cortex-A510 core, a speculatively executed unprivileged
1089	  load might leak data from a privileged level via a cache side channel.
1090
1091	  Work around this problem by executing a TLBI before returning to EL0.
1092
1093	  If unsure, say Y.
1094
1095config ARM64_ERRATUM_3194386
1096	bool "Cortex-*/Neoverse-*: workaround for MSR SSBS not self-synchronizing"
1097	default y
1098	help
1099	  This option adds the workaround for the following errata:
1100
1101	  * ARM Cortex-A76 erratum 3324349
1102	  * ARM Cortex-A77 erratum 3324348
1103	  * ARM Cortex-A78 erratum 3324344
1104	  * ARM Cortex-A78C erratum 3324346
1105	  * ARM Cortex-A78C erratum 3324347
1106	  * ARM Cortex-A710 erratam 3324338
1107	  * ARM Cortex-A715 errartum 3456084
1108	  * ARM Cortex-A720 erratum 3456091
1109	  * ARM Cortex-A725 erratum 3456106
1110	  * ARM Cortex-X1 erratum 3324344
1111	  * ARM Cortex-X1C erratum 3324346
1112	  * ARM Cortex-X2 erratum 3324338
1113	  * ARM Cortex-X3 erratum 3324335
1114	  * ARM Cortex-X4 erratum 3194386
1115	  * ARM Cortex-X925 erratum 3324334
1116	  * ARM Neoverse-N1 erratum 3324349
1117	  * ARM Neoverse N2 erratum 3324339
1118	  * ARM Neoverse-N3 erratum 3456111
1119	  * ARM Neoverse-V1 erratum 3324341
1120	  * ARM Neoverse V2 erratum 3324336
1121	  * ARM Neoverse-V3 erratum 3312417
1122
1123	  On affected cores "MSR SSBS, #0" instructions may not affect
1124	  subsequent speculative instructions, which may permit unexepected
1125	  speculative store bypassing.
1126
1127	  Work around this problem by placing a Speculation Barrier (SB) or
1128	  Instruction Synchronization Barrier (ISB) after kernel changes to
1129	  SSBS. The presence of the SSBS special-purpose register is hidden
1130	  from hwcaps and EL0 reads of ID_AA64PFR1_EL1, such that userspace
1131	  will use the PR_SPEC_STORE_BYPASS prctl to change SSBS.
1132
1133	  If unsure, say Y.
1134
1135config CAVIUM_ERRATUM_22375
1136	bool "Cavium erratum 22375, 24313"
1137	default y
1138	help
1139	  Enable workaround for errata 22375 and 24313.
1140
1141	  This implements two gicv3-its errata workarounds for ThunderX. Both
1142	  with a small impact affecting only ITS table allocation.
1143
1144	    erratum 22375: only alloc 8MB table size
1145	    erratum 24313: ignore memory access type
1146
1147	  The fixes are in ITS initialization and basically ignore memory access
1148	  type and table size provided by the TYPER and BASER registers.
1149
1150	  If unsure, say Y.
1151
1152config CAVIUM_ERRATUM_23144
1153	bool "Cavium erratum 23144: ITS SYNC hang on dual socket system"
1154	depends on NUMA
1155	default y
1156	help
1157	  ITS SYNC command hang for cross node io and collections/cpu mapping.
1158
1159	  If unsure, say Y.
1160
1161config CAVIUM_ERRATUM_23154
1162	bool "Cavium errata 23154 and 38545: GICv3 lacks HW synchronisation"
1163	default y
1164	help
1165	  The ThunderX GICv3 implementation requires a modified version for
1166	  reading the IAR status to ensure data synchronization
1167	  (access to icc_iar1_el1 is not sync'ed before and after).
1168
1169	  It also suffers from erratum 38545 (also present on Marvell's
1170	  OcteonTX and OcteonTX2), resulting in deactivated interrupts being
1171	  spuriously presented to the CPU interface.
1172
1173	  If unsure, say Y.
1174
1175config CAVIUM_ERRATUM_27456
1176	bool "Cavium erratum 27456: Broadcast TLBI instructions may cause icache corruption"
1177	default y
1178	help
1179	  On ThunderX T88 pass 1.x through 2.1 parts, broadcast TLBI
1180	  instructions may cause the icache to become corrupted if it
1181	  contains data for a non-current ASID.  The fix is to
1182	  invalidate the icache when changing the mm context.
1183
1184	  If unsure, say Y.
1185
1186config CAVIUM_ERRATUM_30115
1187	bool "Cavium erratum 30115: Guest may disable interrupts in host"
1188	default y
1189	help
1190	  On ThunderX T88 pass 1.x through 2.2, T81 pass 1.0 through
1191	  1.2, and T83 Pass 1.0, KVM guest execution may disable
1192	  interrupts in host. Trapping both GICv3 group-0 and group-1
1193	  accesses sidesteps the issue.
1194
1195	  If unsure, say Y.
1196
1197config CAVIUM_TX2_ERRATUM_219
1198	bool "Cavium ThunderX2 erratum 219: PRFM between TTBR change and ISB fails"
1199	default y
1200	help
1201	  On Cavium ThunderX2, a load, store or prefetch instruction between a
1202	  TTBR update and the corresponding context synchronizing operation can
1203	  cause a spurious Data Abort to be delivered to any hardware thread in
1204	  the CPU core.
1205
1206	  Work around the issue by avoiding the problematic code sequence and
1207	  trapping KVM guest TTBRx_EL1 writes to EL2 when SMT is enabled. The
1208	  trap handler performs the corresponding register access, skips the
1209	  instruction and ensures context synchronization by virtue of the
1210	  exception return.
1211
1212	  If unsure, say Y.
1213
1214config FUJITSU_ERRATUM_010001
1215	bool "Fujitsu-A64FX erratum E#010001: Undefined fault may occur wrongly"
1216	default y
1217	help
1218	  This option adds a workaround for Fujitsu-A64FX erratum E#010001.
1219	  On some variants of the Fujitsu-A64FX cores ver(1.0, 1.1), memory
1220	  accesses may cause undefined fault (Data abort, DFSC=0b111111).
1221	  This fault occurs under a specific hardware condition when a
1222	  load/store instruction performs an address translation using:
1223	  case-1  TTBR0_EL1 with TCR_EL1.NFD0 == 1.
1224	  case-2  TTBR0_EL2 with TCR_EL2.NFD0 == 1.
1225	  case-3  TTBR1_EL1 with TCR_EL1.NFD1 == 1.
1226	  case-4  TTBR1_EL2 with TCR_EL2.NFD1 == 1.
1227
1228	  The workaround is to ensure these bits are clear in TCR_ELx.
1229	  The workaround only affects the Fujitsu-A64FX.
1230
1231	  If unsure, say Y.
1232
1233config HISILICON_ERRATUM_161600802
1234	bool "Hip07 161600802: Erroneous redistributor VLPI base"
1235	default y
1236	help
1237	  The HiSilicon Hip07 SoC uses the wrong redistributor base
1238	  when issued ITS commands such as VMOVP and VMAPP, and requires
1239	  a 128kB offset to be applied to the target address in this commands.
1240
1241	  If unsure, say Y.
1242
1243config HISILICON_ERRATUM_162100801
1244	bool "Hip09 162100801 erratum support"
1245	default y
1246	help
1247	  When enabling GICv4.1 in hip09, VMAPP will fail to clear some caches
1248	  during unmapping operation, which will cause some vSGIs lost.
1249	  To fix the issue, invalidate related vPE cache through GICR_INVALLR
1250	  after VMOVP.
1251
1252	  If unsure, say Y.
1253
1254config QCOM_FALKOR_ERRATUM_1003
1255	bool "Falkor E1003: Incorrect translation due to ASID change"
1256	default y
1257	help
1258	  On Falkor v1, an incorrect ASID may be cached in the TLB when ASID
1259	  and BADDR are changed together in TTBRx_EL1. Since we keep the ASID
1260	  in TTBR1_EL1, this situation only occurs in the entry trampoline and
1261	  then only for entries in the walk cache, since the leaf translation
1262	  is unchanged. Work around the erratum by invalidating the walk cache
1263	  entries for the trampoline before entering the kernel proper.
1264
1265config QCOM_FALKOR_ERRATUM_1009
1266	bool "Falkor E1009: Prematurely complete a DSB after a TLBI"
1267	default y
1268	select ARM64_WORKAROUND_REPEAT_TLBI
1269	help
1270	  On Falkor v1, the CPU may prematurely complete a DSB following a
1271	  TLBI xxIS invalidate maintenance operation. Repeat the TLBI operation
1272	  one more time to fix the issue.
1273
1274	  If unsure, say Y.
1275
1276config QCOM_QDF2400_ERRATUM_0065
1277	bool "QDF2400 E0065: Incorrect GITS_TYPER.ITT_Entry_size"
1278	default y
1279	help
1280	  On Qualcomm Datacenter Technologies QDF2400 SoC, ITS hardware reports
1281	  ITE size incorrectly. The GITS_TYPER.ITT_Entry_size field should have
1282	  been indicated as 16Bytes (0xf), not 8Bytes (0x7).
1283
1284	  If unsure, say Y.
1285
1286config QCOM_FALKOR_ERRATUM_E1041
1287	bool "Falkor E1041: Speculative instruction fetches might cause errant memory access"
1288	default y
1289	help
1290	  Falkor CPU may speculatively fetch instructions from an improper
1291	  memory location when MMU translation is changed from SCTLR_ELn[M]=1
1292	  to SCTLR_ELn[M]=0. Prefix an ISB instruction to fix the problem.
1293
1294	  If unsure, say Y.
1295
1296config NVIDIA_CARMEL_CNP_ERRATUM
1297	bool "NVIDIA Carmel CNP: CNP on Carmel semantically different than ARM cores"
1298	default y
1299	help
1300	  If CNP is enabled on Carmel cores, non-sharable TLBIs on a core will not
1301	  invalidate shared TLB entries installed by a different core, as it would
1302	  on standard ARM cores.
1303
1304	  If unsure, say Y.
1305
1306config ROCKCHIP_ERRATUM_3568002
1307	bool "Rockchip 3568002: GIC600 can not access physical addresses higher than 4GB"
1308	default y
1309	help
1310	  The Rockchip RK3566 and RK3568 GIC600 SoC integrations have AXI
1311	  addressing limited to the first 32bit of physical address space.
1312
1313	  If unsure, say Y.
1314
1315config ROCKCHIP_ERRATUM_3588001
1316	bool "Rockchip 3588001: GIC600 can not support shareability attributes"
1317	default y
1318	help
1319	  The Rockchip RK3588 GIC600 SoC integration does not support ACE/ACE-lite.
1320	  This means, that its sharability feature may not be used, even though it
1321	  is supported by the IP itself.
1322
1323	  If unsure, say Y.
1324
1325config SOCIONEXT_SYNQUACER_PREITS
1326	bool "Socionext Synquacer: Workaround for GICv3 pre-ITS"
1327	default y
1328	help
1329	  Socionext Synquacer SoCs implement a separate h/w block to generate
1330	  MSI doorbell writes with non-zero values for the device ID.
1331
1332	  If unsure, say Y.
1333
1334endmenu # "ARM errata workarounds via the alternatives framework"
1335
1336choice
1337	prompt "Page size"
1338	default ARM64_4K_PAGES
1339	help
1340	  Page size (translation granule) configuration.
1341
1342config ARM64_4K_PAGES
1343	bool "4KB"
1344	select HAVE_PAGE_SIZE_4KB
1345	help
1346	  This feature enables 4KB pages support.
1347
1348config ARM64_16K_PAGES
1349	bool "16KB"
1350	select HAVE_PAGE_SIZE_16KB
1351	help
1352	  The system will use 16KB pages support. AArch32 emulation
1353	  requires applications compiled with 16K (or a multiple of 16K)
1354	  aligned segments.
1355
1356config ARM64_64K_PAGES
1357	bool "64KB"
1358	select HAVE_PAGE_SIZE_64KB
1359	help
1360	  This feature enables 64KB pages support (4KB by default)
1361	  allowing only two levels of page tables and faster TLB
1362	  look-up. AArch32 emulation requires applications compiled
1363	  with 64K aligned segments.
1364
1365endchoice
1366
1367choice
1368	prompt "Virtual address space size"
1369	default ARM64_VA_BITS_52
1370	help
1371	  Allows choosing one of multiple possible virtual address
1372	  space sizes. The level of translation table is determined by
1373	  a combination of page size and virtual address space size.
1374
1375config ARM64_VA_BITS_36
1376	bool "36-bit" if EXPERT
1377	depends on PAGE_SIZE_16KB
1378
1379config ARM64_VA_BITS_39
1380	bool "39-bit"
1381	depends on PAGE_SIZE_4KB
1382
1383config ARM64_VA_BITS_42
1384	bool "42-bit"
1385	depends on PAGE_SIZE_64KB
1386
1387config ARM64_VA_BITS_47
1388	bool "47-bit"
1389	depends on PAGE_SIZE_16KB
1390
1391config ARM64_VA_BITS_48
1392	bool "48-bit"
1393
1394config ARM64_VA_BITS_52
1395	bool "52-bit"
1396	help
1397	  Enable 52-bit virtual addressing for userspace when explicitly
1398	  requested via a hint to mmap(). The kernel will also use 52-bit
1399	  virtual addresses for its own mappings (provided HW support for
1400	  this feature is available, otherwise it reverts to 48-bit).
1401
1402	  NOTE: Enabling 52-bit virtual addressing in conjunction with
1403	  ARMv8.3 Pointer Authentication will result in the PAC being
1404	  reduced from 7 bits to 3 bits, which may have a significant
1405	  impact on its susceptibility to brute-force attacks.
1406
1407	  If unsure, select 48-bit virtual addressing instead.
1408
1409endchoice
1410
1411config ARM64_FORCE_52BIT
1412	bool "Force 52-bit virtual addresses for userspace"
1413	depends on ARM64_VA_BITS_52 && EXPERT
1414	help
1415	  For systems with 52-bit userspace VAs enabled, the kernel will attempt
1416	  to maintain compatibility with older software by providing 48-bit VAs
1417	  unless a hint is supplied to mmap.
1418
1419	  This configuration option disables the 48-bit compatibility logic, and
1420	  forces all userspace addresses to be 52-bit on HW that supports it. One
1421	  should only enable this configuration option for stress testing userspace
1422	  memory management code. If unsure say N here.
1423
1424config ARM64_VA_BITS
1425	int
1426	default 36 if ARM64_VA_BITS_36
1427	default 39 if ARM64_VA_BITS_39
1428	default 42 if ARM64_VA_BITS_42
1429	default 47 if ARM64_VA_BITS_47
1430	default 48 if ARM64_VA_BITS_48
1431	default 52 if ARM64_VA_BITS_52
1432
1433choice
1434	prompt "Physical address space size"
1435	default ARM64_PA_BITS_48
1436	help
1437	  Choose the maximum physical address range that the kernel will
1438	  support.
1439
1440config ARM64_PA_BITS_48
1441	bool "48-bit"
1442	depends on ARM64_64K_PAGES || !ARM64_VA_BITS_52
1443
1444config ARM64_PA_BITS_52
1445	bool "52-bit"
1446	depends on ARM64_64K_PAGES || ARM64_VA_BITS_52
1447	help
1448	  Enable support for a 52-bit physical address space, introduced as
1449	  part of the ARMv8.2-LPA extension.
1450
1451	  With this enabled, the kernel will also continue to work on CPUs that
1452	  do not support ARMv8.2-LPA, but with some added memory overhead (and
1453	  minor performance overhead).
1454
1455endchoice
1456
1457config ARM64_PA_BITS
1458	int
1459	default 48 if ARM64_PA_BITS_48
1460	default 52 if ARM64_PA_BITS_52
1461
1462config ARM64_LPA2
1463	def_bool y
1464	depends on ARM64_PA_BITS_52 && !ARM64_64K_PAGES
1465
1466choice
1467	prompt "Endianness"
1468	default CPU_LITTLE_ENDIAN
1469	help
1470	  Select the endianness of data accesses performed by the CPU. Userspace
1471	  applications will need to be compiled and linked for the endianness
1472	  that is selected here.
1473
1474config CPU_BIG_ENDIAN
1475	bool "Build big-endian kernel"
1476	# https://github.com/llvm/llvm-project/commit/1379b150991f70a5782e9a143c2ba5308da1161c
1477	depends on AS_IS_GNU || AS_VERSION >= 150000
1478	help
1479	  Say Y if you plan on running a kernel with a big-endian userspace.
1480
1481config CPU_LITTLE_ENDIAN
1482	bool "Build little-endian kernel"
1483	help
1484	  Say Y if you plan on running a kernel with a little-endian userspace.
1485	  This is usually the case for distributions targeting arm64.
1486
1487endchoice
1488
1489config SCHED_MC
1490	bool "Multi-core scheduler support"
1491	help
1492	  Multi-core scheduler support improves the CPU scheduler's decision
1493	  making when dealing with multi-core CPU chips at a cost of slightly
1494	  increased overhead in some places. If unsure say N here.
1495
1496config SCHED_CLUSTER
1497	bool "Cluster scheduler support"
1498	help
1499	  Cluster scheduler support improves the CPU scheduler's decision
1500	  making when dealing with machines that have clusters of CPUs.
1501	  Cluster usually means a couple of CPUs which are placed closely
1502	  by sharing mid-level caches, last-level cache tags or internal
1503	  busses.
1504
1505config SCHED_SMT
1506	bool "SMT scheduler support"
1507	help
1508	  Improves the CPU scheduler's decision making when dealing with
1509	  MultiThreading at a cost of slightly increased overhead in some
1510	  places. If unsure say N here.
1511
1512config NR_CPUS
1513	int "Maximum number of CPUs (2-4096)"
1514	range 2 4096
1515	default "512"
1516
1517config HOTPLUG_CPU
1518	bool "Support for hot-pluggable CPUs"
1519	select GENERIC_IRQ_MIGRATION
1520	help
1521	  Say Y here to experiment with turning CPUs off and on.  CPUs
1522	  can be controlled through /sys/devices/system/cpu.
1523
1524# Common NUMA Features
1525config NUMA
1526	bool "NUMA Memory Allocation and Scheduler Support"
1527	select GENERIC_ARCH_NUMA
1528	select OF_NUMA
1529	select HAVE_SETUP_PER_CPU_AREA
1530	select NEED_PER_CPU_EMBED_FIRST_CHUNK
1531	select NEED_PER_CPU_PAGE_FIRST_CHUNK
1532	select USE_PERCPU_NUMA_NODE_ID
1533	help
1534	  Enable NUMA (Non-Uniform Memory Access) support.
1535
1536	  The kernel will try to allocate memory used by a CPU on the
1537	  local memory of the CPU and add some more
1538	  NUMA awareness to the kernel.
1539
1540config NODES_SHIFT
1541	int "Maximum NUMA Nodes (as a power of 2)"
1542	range 1 10
1543	default "4"
1544	depends on NUMA
1545	help
1546	  Specify the maximum number of NUMA Nodes available on the target
1547	  system.  Increases memory reserved to accommodate various tables.
1548
1549source "kernel/Kconfig.hz"
1550
1551config ARCH_SPARSEMEM_ENABLE
1552	def_bool y
1553	select SPARSEMEM_VMEMMAP_ENABLE
1554	select SPARSEMEM_VMEMMAP
1555
1556config HW_PERF_EVENTS
1557	def_bool y
1558	depends on ARM_PMU
1559
1560# Supported by clang >= 7.0 or GCC >= 12.0.0
1561config CC_HAVE_SHADOW_CALL_STACK
1562	def_bool $(cc-option, -fsanitize=shadow-call-stack -ffixed-x18)
1563
1564config PARAVIRT
1565	bool "Enable paravirtualization code"
1566	help
1567	  This changes the kernel so it can modify itself when it is run
1568	  under a hypervisor, potentially improving performance significantly
1569	  over full virtualization.
1570
1571config PARAVIRT_TIME_ACCOUNTING
1572	bool "Paravirtual steal time accounting"
1573	select PARAVIRT
1574	help
1575	  Select this option to enable fine granularity task steal time
1576	  accounting. Time spent executing other tasks in parallel with
1577	  the current vCPU is discounted from the vCPU power. To account for
1578	  that, there can be a small performance impact.
1579
1580	  If in doubt, say N here.
1581
1582config ARCH_SUPPORTS_KEXEC
1583	def_bool PM_SLEEP_SMP
1584
1585config ARCH_SUPPORTS_KEXEC_FILE
1586	def_bool y
1587
1588config ARCH_SELECTS_KEXEC_FILE
1589	def_bool y
1590	depends on KEXEC_FILE
1591	select HAVE_IMA_KEXEC if IMA
1592
1593config ARCH_SUPPORTS_KEXEC_SIG
1594	def_bool y
1595
1596config ARCH_SUPPORTS_KEXEC_IMAGE_VERIFY_SIG
1597	def_bool y
1598
1599config ARCH_DEFAULT_KEXEC_IMAGE_VERIFY_SIG
1600	def_bool y
1601
1602config ARCH_SUPPORTS_CRASH_DUMP
1603	def_bool y
1604
1605config ARCH_DEFAULT_CRASH_DUMP
1606	def_bool y
1607
1608config ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION
1609	def_bool CRASH_RESERVE
1610
1611config TRANS_TABLE
1612	def_bool y
1613	depends on HIBERNATION || KEXEC_CORE
1614
1615config XEN_DOM0
1616	def_bool y
1617	depends on XEN
1618
1619config XEN
1620	bool "Xen guest support on ARM64"
1621	depends on ARM64 && OF
1622	select SWIOTLB_XEN
1623	select PARAVIRT
1624	help
1625	  Say Y if you want to run Linux in a Virtual Machine on Xen on ARM64.
1626
1627# include/linux/mmzone.h requires the following to be true:
1628#
1629#   MAX_PAGE_ORDER + PAGE_SHIFT <= SECTION_SIZE_BITS
1630#
1631# so the maximum value of MAX_PAGE_ORDER is SECTION_SIZE_BITS - PAGE_SHIFT:
1632#
1633#     | SECTION_SIZE_BITS |  PAGE_SHIFT  |  max MAX_PAGE_ORDER  |  default MAX_PAGE_ORDER |
1634# ----+-------------------+--------------+----------------------+-------------------------+
1635# 4K  |       27          |      12      |       15             |         10              |
1636# 16K |       27          |      14      |       13             |         11              |
1637# 64K |       29          |      16      |       13             |         13              |
1638config ARCH_FORCE_MAX_ORDER
1639	int
1640	default "13" if ARM64_64K_PAGES
1641	default "11" if ARM64_16K_PAGES
1642	default "10"
1643	help
1644	  The kernel page allocator limits the size of maximal physically
1645	  contiguous allocations. The limit is called MAX_PAGE_ORDER and it
1646	  defines the maximal power of two of number of pages that can be
1647	  allocated as a single contiguous block. This option allows
1648	  overriding the default setting when ability to allocate very
1649	  large blocks of physically contiguous memory is required.
1650
1651	  The maximal size of allocation cannot exceed the size of the
1652	  section, so the value of MAX_PAGE_ORDER should satisfy
1653
1654	    MAX_PAGE_ORDER + PAGE_SHIFT <= SECTION_SIZE_BITS
1655
1656	  Don't change if unsure.
1657
1658config UNMAP_KERNEL_AT_EL0
1659	bool "Unmap kernel when running in userspace (KPTI)" if EXPERT
1660	default y
1661	help
1662	  Speculation attacks against some high-performance processors can
1663	  be used to bypass MMU permission checks and leak kernel data to
1664	  userspace. This can be defended against by unmapping the kernel
1665	  when running in userspace, mapping it back in on exception entry
1666	  via a trampoline page in the vector table.
1667
1668	  If unsure, say Y.
1669
1670config MITIGATE_SPECTRE_BRANCH_HISTORY
1671	bool "Mitigate Spectre style attacks against branch history" if EXPERT
1672	default y
1673	help
1674	  Speculation attacks against some high-performance processors can
1675	  make use of branch history to influence future speculation.
1676	  When taking an exception from user-space, a sequence of branches
1677	  or a firmware call overwrites the branch history.
1678
1679config RODATA_FULL_DEFAULT_ENABLED
1680	bool "Apply r/o permissions of VM areas also to their linear aliases"
1681	default y
1682	help
1683	  Apply read-only attributes of VM areas to the linear alias of
1684	  the backing pages as well. This prevents code or read-only data
1685	  from being modified (inadvertently or intentionally) via another
1686	  mapping of the same memory page. This additional enhancement can
1687	  be turned off at runtime by passing rodata=[off|on] (and turned on
1688	  with rodata=full if this option is set to 'n')
1689
1690	  This requires the linear region to be mapped down to pages,
1691	  which may adversely affect performance in some cases.
1692
1693config ARM64_SW_TTBR0_PAN
1694	bool "Emulate Privileged Access Never using TTBR0_EL1 switching"
1695	depends on !KCSAN
1696	select ARM64_PAN
1697	help
1698	  Enabling this option prevents the kernel from accessing
1699	  user-space memory directly by pointing TTBR0_EL1 to a reserved
1700	  zeroed area and reserved ASID. The user access routines
1701	  restore the valid TTBR0_EL1 temporarily.
1702
1703config ARM64_TAGGED_ADDR_ABI
1704	bool "Enable the tagged user addresses syscall ABI"
1705	default y
1706	help
1707	  When this option is enabled, user applications can opt in to a
1708	  relaxed ABI via prctl() allowing tagged addresses to be passed
1709	  to system calls as pointer arguments. For details, see
1710	  Documentation/arch/arm64/tagged-address-abi.rst.
1711
1712menuconfig COMPAT
1713	bool "Kernel support for 32-bit EL0"
1714	depends on ARM64_4K_PAGES || EXPERT
1715	select HAVE_UID16
1716	select OLD_SIGSUSPEND3
1717	select COMPAT_OLD_SIGACTION
1718	help
1719	  This option enables support for a 32-bit EL0 running under a 64-bit
1720	  kernel at EL1. AArch32-specific components such as system calls,
1721	  the user helper functions, VFP support and the ptrace interface are
1722	  handled appropriately by the kernel.
1723
1724	  If you use a page size other than 4KB (i.e, 16KB or 64KB), please be aware
1725	  that you will only be able to execute AArch32 binaries that were compiled
1726	  with page size aligned segments.
1727
1728	  If you want to execute 32-bit userspace applications, say Y.
1729
1730if COMPAT
1731
1732config KUSER_HELPERS
1733	bool "Enable kuser helpers page for 32-bit applications"
1734	default y
1735	help
1736	  Warning: disabling this option may break 32-bit user programs.
1737
1738	  Provide kuser helpers to compat tasks. The kernel provides
1739	  helper code to userspace in read only form at a fixed location
1740	  to allow userspace to be independent of the CPU type fitted to
1741	  the system. This permits binaries to be run on ARMv4 through
1742	  to ARMv8 without modification.
1743
1744	  See Documentation/arch/arm/kernel_user_helpers.rst for details.
1745
1746	  However, the fixed address nature of these helpers can be used
1747	  by ROP (return orientated programming) authors when creating
1748	  exploits.
1749
1750	  If all of the binaries and libraries which run on your platform
1751	  are built specifically for your platform, and make no use of
1752	  these helpers, then you can turn this option off to hinder
1753	  such exploits. However, in that case, if a binary or library
1754	  relying on those helpers is run, it will not function correctly.
1755
1756	  Say N here only if you are absolutely certain that you do not
1757	  need these helpers; otherwise, the safe option is to say Y.
1758
1759config COMPAT_VDSO
1760	bool "Enable vDSO for 32-bit applications"
1761	depends on !CPU_BIG_ENDIAN
1762	depends on (CC_IS_CLANG && LD_IS_LLD) || "$(CROSS_COMPILE_COMPAT)" != ""
1763	select GENERIC_COMPAT_VDSO
1764	default y
1765	help
1766	  Place in the process address space of 32-bit applications an
1767	  ELF shared object providing fast implementations of gettimeofday
1768	  and clock_gettime.
1769
1770	  You must have a 32-bit build of glibc 2.22 or later for programs
1771	  to seamlessly take advantage of this.
1772
1773config THUMB2_COMPAT_VDSO
1774	bool "Compile the 32-bit vDSO for Thumb-2 mode" if EXPERT
1775	depends on COMPAT_VDSO
1776	default y
1777	help
1778	  Compile the compat vDSO with '-mthumb -fomit-frame-pointer' if y,
1779	  otherwise with '-marm'.
1780
1781config COMPAT_ALIGNMENT_FIXUPS
1782	bool "Fix up misaligned multi-word loads and stores in user space"
1783
1784menuconfig ARMV8_DEPRECATED
1785	bool "Emulate deprecated/obsolete ARMv8 instructions"
1786	depends on SYSCTL
1787	help
1788	  Legacy software support may require certain instructions
1789	  that have been deprecated or obsoleted in the architecture.
1790
1791	  Enable this config to enable selective emulation of these
1792	  features.
1793
1794	  If unsure, say Y
1795
1796if ARMV8_DEPRECATED
1797
1798config SWP_EMULATION
1799	bool "Emulate SWP/SWPB instructions"
1800	help
1801	  ARMv8 obsoletes the use of A32 SWP/SWPB instructions such that
1802	  they are always undefined. Say Y here to enable software
1803	  emulation of these instructions for userspace using LDXR/STXR.
1804	  This feature can be controlled at runtime with the abi.swp
1805	  sysctl which is disabled by default.
1806
1807	  In some older versions of glibc [<=2.8] SWP is used during futex
1808	  trylock() operations with the assumption that the code will not
1809	  be preempted. This invalid assumption may be more likely to fail
1810	  with SWP emulation enabled, leading to deadlock of the user
1811	  application.
1812
1813	  NOTE: when accessing uncached shared regions, LDXR/STXR rely
1814	  on an external transaction monitoring block called a global
1815	  monitor to maintain update atomicity. If your system does not
1816	  implement a global monitor, this option can cause programs that
1817	  perform SWP operations to uncached memory to deadlock.
1818
1819	  If unsure, say Y
1820
1821config CP15_BARRIER_EMULATION
1822	bool "Emulate CP15 Barrier instructions"
1823	help
1824	  The CP15 barrier instructions - CP15ISB, CP15DSB, and
1825	  CP15DMB - are deprecated in ARMv8 (and ARMv7). It is
1826	  strongly recommended to use the ISB, DSB, and DMB
1827	  instructions instead.
1828
1829	  Say Y here to enable software emulation of these
1830	  instructions for AArch32 userspace code. When this option is
1831	  enabled, CP15 barrier usage is traced which can help
1832	  identify software that needs updating. This feature can be
1833	  controlled at runtime with the abi.cp15_barrier sysctl.
1834
1835	  If unsure, say Y
1836
1837config SETEND_EMULATION
1838	bool "Emulate SETEND instruction"
1839	help
1840	  The SETEND instruction alters the data-endianness of the
1841	  AArch32 EL0, and is deprecated in ARMv8.
1842
1843	  Say Y here to enable software emulation of the instruction
1844	  for AArch32 userspace code. This feature can be controlled
1845	  at runtime with the abi.setend sysctl.
1846
1847	  Note: All the cpus on the system must have mixed endian support at EL0
1848	  for this feature to be enabled. If a new CPU - which doesn't support mixed
1849	  endian - is hotplugged in after this feature has been enabled, there could
1850	  be unexpected results in the applications.
1851
1852	  If unsure, say Y
1853endif # ARMV8_DEPRECATED
1854
1855endif # COMPAT
1856
1857menu "ARMv8.1 architectural features"
1858
1859config ARM64_HW_AFDBM
1860	bool "Support for hardware updates of the Access and Dirty page flags"
1861	default y
1862	help
1863	  The ARMv8.1 architecture extensions introduce support for
1864	  hardware updates of the access and dirty information in page
1865	  table entries. When enabled in TCR_EL1 (HA and HD bits) on
1866	  capable processors, accesses to pages with PTE_AF cleared will
1867	  set this bit instead of raising an access flag fault.
1868	  Similarly, writes to read-only pages with the DBM bit set will
1869	  clear the read-only bit (AP[2]) instead of raising a
1870	  permission fault.
1871
1872	  Kernels built with this configuration option enabled continue
1873	  to work on pre-ARMv8.1 hardware and the performance impact is
1874	  minimal. If unsure, say Y.
1875
1876config ARM64_PAN
1877	bool "Enable support for Privileged Access Never (PAN)"
1878	default y
1879	help
1880	  Privileged Access Never (PAN; part of the ARMv8.1 Extensions)
1881	  prevents the kernel or hypervisor from accessing user-space (EL0)
1882	  memory directly.
1883
1884	  Choosing this option will cause any unprotected (not using
1885	  copy_to_user et al) memory access to fail with a permission fault.
1886
1887	  The feature is detected at runtime, and will remain as a 'nop'
1888	  instruction if the cpu does not implement the feature.
1889
1890config ARM64_LSE_ATOMICS
1891	bool
1892	default ARM64_USE_LSE_ATOMICS
1893
1894config ARM64_USE_LSE_ATOMICS
1895	bool "Atomic instructions"
1896	default y
1897	help
1898	  As part of the Large System Extensions, ARMv8.1 introduces new
1899	  atomic instructions that are designed specifically to scale in
1900	  very large systems.
1901
1902	  Say Y here to make use of these instructions for the in-kernel
1903	  atomic routines. This incurs a small overhead on CPUs that do
1904	  not support these instructions.
1905
1906endmenu # "ARMv8.1 architectural features"
1907
1908menu "ARMv8.2 architectural features"
1909
1910config ARM64_PMEM
1911	bool "Enable support for persistent memory"
1912	select ARCH_HAS_PMEM_API
1913	select ARCH_HAS_UACCESS_FLUSHCACHE
1914	help
1915	  Say Y to enable support for the persistent memory API based on the
1916	  ARMv8.2 DCPoP feature.
1917
1918	  The feature is detected at runtime, and the kernel will use DC CVAC
1919	  operations if DC CVAP is not supported (following the behaviour of
1920	  DC CVAP itself if the system does not define a point of persistence).
1921
1922config ARM64_RAS_EXTN
1923	bool "Enable support for RAS CPU Extensions"
1924	default y
1925	help
1926	  CPUs that support the Reliability, Availability and Serviceability
1927	  (RAS) Extensions, part of ARMv8.2 are able to track faults and
1928	  errors, classify them and report them to software.
1929
1930	  On CPUs with these extensions system software can use additional
1931	  barriers to determine if faults are pending and read the
1932	  classification from a new set of registers.
1933
1934	  Selecting this feature will allow the kernel to use these barriers
1935	  and access the new registers if the system supports the extension.
1936	  Platform RAS features may additionally depend on firmware support.
1937
1938config ARM64_CNP
1939	bool "Enable support for Common Not Private (CNP) translations"
1940	default y
1941	help
1942	  Common Not Private (CNP) allows translation table entries to
1943	  be shared between different PEs in the same inner shareable
1944	  domain, so the hardware can use this fact to optimise the
1945	  caching of such entries in the TLB.
1946
1947	  Selecting this option allows the CNP feature to be detected
1948	  at runtime, and does not affect PEs that do not implement
1949	  this feature.
1950
1951endmenu # "ARMv8.2 architectural features"
1952
1953menu "ARMv8.3 architectural features"
1954
1955config ARM64_PTR_AUTH
1956	bool "Enable support for pointer authentication"
1957	default y
1958	help
1959	  Pointer authentication (part of the ARMv8.3 Extensions) provides
1960	  instructions for signing and authenticating pointers against secret
1961	  keys, which can be used to mitigate Return Oriented Programming (ROP)
1962	  and other attacks.
1963
1964	  This option enables these instructions at EL0 (i.e. for userspace).
1965	  Choosing this option will cause the kernel to initialise secret keys
1966	  for each process at exec() time, with these keys being
1967	  context-switched along with the process.
1968
1969	  The feature is detected at runtime. If the feature is not present in
1970	  hardware it will not be advertised to userspace/KVM guest nor will it
1971	  be enabled.
1972
1973	  If the feature is present on the boot CPU but not on a late CPU, then
1974	  the late CPU will be parked. Also, if the boot CPU does not have
1975	  address auth and the late CPU has then the late CPU will still boot
1976	  but with the feature disabled. On such a system, this option should
1977	  not be selected.
1978
1979config ARM64_PTR_AUTH_KERNEL
1980	bool "Use pointer authentication for kernel"
1981	default y
1982	depends on ARM64_PTR_AUTH
1983	# Modern compilers insert a .note.gnu.property section note for PAC
1984	# which is only understood by binutils starting with version 2.33.1.
1985	depends on LD_IS_LLD || LD_VERSION >= 23301 || (CC_IS_GCC && GCC_VERSION < 90100)
1986	depends on !CC_IS_CLANG || AS_HAS_CFI_NEGATE_RA_STATE
1987	depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_ARGS)
1988	help
1989	  If the compiler supports the -mbranch-protection or
1990	  -msign-return-address flag (e.g. GCC 7 or later), then this option
1991	  will cause the kernel itself to be compiled with return address
1992	  protection. In this case, and if the target hardware is known to
1993	  support pointer authentication, then CONFIG_STACKPROTECTOR can be
1994	  disabled with minimal loss of protection.
1995
1996	  This feature works with FUNCTION_GRAPH_TRACER option only if
1997	  DYNAMIC_FTRACE_WITH_ARGS is enabled.
1998
1999config CC_HAS_BRANCH_PROT_PAC_RET
2000	# GCC 9 or later, clang 8 or later
2001	def_bool $(cc-option,-mbranch-protection=pac-ret+leaf)
2002
2003config AS_HAS_CFI_NEGATE_RA_STATE
2004	# binutils 2.34+
2005	def_bool $(as-instr,.cfi_startproc\n.cfi_negate_ra_state\n.cfi_endproc\n)
2006
2007endmenu # "ARMv8.3 architectural features"
2008
2009menu "ARMv8.4 architectural features"
2010
2011config ARM64_AMU_EXTN
2012	bool "Enable support for the Activity Monitors Unit CPU extension"
2013	default y
2014	help
2015	  The activity monitors extension is an optional extension introduced
2016	  by the ARMv8.4 CPU architecture. This enables support for version 1
2017	  of the activity monitors architecture, AMUv1.
2018
2019	  To enable the use of this extension on CPUs that implement it, say Y.
2020
2021	  Note that for architectural reasons, firmware _must_ implement AMU
2022	  support when running on CPUs that present the activity monitors
2023	  extension. The required support is present in:
2024	    * Version 1.5 and later of the ARM Trusted Firmware
2025
2026	  For kernels that have this configuration enabled but boot with broken
2027	  firmware, you may need to say N here until the firmware is fixed.
2028	  Otherwise you may experience firmware panics or lockups when
2029	  accessing the counter registers. Even if you are not observing these
2030	  symptoms, the values returned by the register reads might not
2031	  correctly reflect reality. Most commonly, the value read will be 0,
2032	  indicating that the counter is not enabled.
2033
2034config ARM64_TLB_RANGE
2035	bool "Enable support for tlbi range feature"
2036	default y
2037	help
2038	  ARMv8.4-TLBI provides TLBI invalidation instruction that apply to a
2039	  range of input addresses.
2040
2041endmenu # "ARMv8.4 architectural features"
2042
2043menu "ARMv8.5 architectural features"
2044
2045config AS_HAS_ARMV8_5
2046	def_bool $(cc-option,-Wa$(comma)-march=armv8.5-a)
2047
2048config ARM64_BTI
2049	bool "Branch Target Identification support"
2050	default y
2051	help
2052	  Branch Target Identification (part of the ARMv8.5 Extensions)
2053	  provides a mechanism to limit the set of locations to which computed
2054	  branch instructions such as BR or BLR can jump.
2055
2056	  To make use of BTI on CPUs that support it, say Y.
2057
2058	  BTI is intended to provide complementary protection to other control
2059	  flow integrity protection mechanisms, such as the Pointer
2060	  authentication mechanism provided as part of the ARMv8.3 Extensions.
2061	  For this reason, it does not make sense to enable this option without
2062	  also enabling support for pointer authentication.  Thus, when
2063	  enabling this option you should also select ARM64_PTR_AUTH=y.
2064
2065	  Userspace binaries must also be specifically compiled to make use of
2066	  this mechanism.  If you say N here or the hardware does not support
2067	  BTI, such binaries can still run, but you get no additional
2068	  enforcement of branch destinations.
2069
2070config ARM64_BTI_KERNEL
2071	bool "Use Branch Target Identification for kernel"
2072	default y
2073	depends on ARM64_BTI
2074	depends on ARM64_PTR_AUTH_KERNEL
2075	depends on CC_HAS_BRANCH_PROT_PAC_RET_BTI
2076	# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94697
2077	depends on !CC_IS_GCC || GCC_VERSION >= 100100
2078	# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106671
2079	depends on !CC_IS_GCC
2080	depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_ARGS)
2081	help
2082	  Build the kernel with Branch Target Identification annotations
2083	  and enable enforcement of this for kernel code. When this option
2084	  is enabled and the system supports BTI all kernel code including
2085	  modular code must have BTI enabled.
2086
2087config CC_HAS_BRANCH_PROT_PAC_RET_BTI
2088	# GCC 9 or later, clang 8 or later
2089	def_bool $(cc-option,-mbranch-protection=pac-ret+leaf+bti)
2090
2091config ARM64_E0PD
2092	bool "Enable support for E0PD"
2093	default y
2094	help
2095	  E0PD (part of the ARMv8.5 extensions) allows us to ensure
2096	  that EL0 accesses made via TTBR1 always fault in constant time,
2097	  providing similar benefits to KASLR as those provided by KPTI, but
2098	  with lower overhead and without disrupting legitimate access to
2099	  kernel memory such as SPE.
2100
2101	  This option enables E0PD for TTBR1 where available.
2102
2103config ARM64_AS_HAS_MTE
2104	# Initial support for MTE went in binutils 2.32.0, checked with
2105	# ".arch armv8.5-a+memtag" below. However, this was incomplete
2106	# as a late addition to the final architecture spec (LDGM/STGM)
2107	# is only supported in the newer 2.32.x and 2.33 binutils
2108	# versions, hence the extra "stgm" instruction check below.
2109	def_bool $(as-instr,.arch armv8.5-a+memtag\nstgm xzr$(comma)[x0])
2110
2111config ARM64_MTE
2112	bool "Memory Tagging Extension support"
2113	default y
2114	depends on ARM64_AS_HAS_MTE && ARM64_TAGGED_ADDR_ABI
2115	depends on AS_HAS_ARMV8_5
2116	# Required for tag checking in the uaccess routines
2117	select ARM64_PAN
2118	select ARCH_HAS_SUBPAGE_FAULTS
2119	select ARCH_USES_HIGH_VMA_FLAGS
2120	select ARCH_USES_PG_ARCH_2
2121	select ARCH_USES_PG_ARCH_3
2122	help
2123	  Memory Tagging (part of the ARMv8.5 Extensions) provides
2124	  architectural support for run-time, always-on detection of
2125	  various classes of memory error to aid with software debugging
2126	  to eliminate vulnerabilities arising from memory-unsafe
2127	  languages.
2128
2129	  This option enables the support for the Memory Tagging
2130	  Extension at EL0 (i.e. for userspace).
2131
2132	  Selecting this option allows the feature to be detected at
2133	  runtime. Any secondary CPU not implementing this feature will
2134	  not be allowed a late bring-up.
2135
2136	  Userspace binaries that want to use this feature must
2137	  explicitly opt in. The mechanism for the userspace is
2138	  described in:
2139
2140	  Documentation/arch/arm64/memory-tagging-extension.rst.
2141
2142endmenu # "ARMv8.5 architectural features"
2143
2144menu "ARMv8.7 architectural features"
2145
2146config ARM64_EPAN
2147	bool "Enable support for Enhanced Privileged Access Never (EPAN)"
2148	default y
2149	depends on ARM64_PAN
2150	help
2151	  Enhanced Privileged Access Never (EPAN) allows Privileged
2152	  Access Never to be used with Execute-only mappings.
2153
2154	  The feature is detected at runtime, and will remain disabled
2155	  if the cpu does not implement the feature.
2156endmenu # "ARMv8.7 architectural features"
2157
2158config AS_HAS_MOPS
2159	def_bool $(as-instr,.arch_extension mops)
2160
2161menu "ARMv8.9 architectural features"
2162
2163config ARM64_POE
2164	prompt "Permission Overlay Extension"
2165	def_bool y
2166	select ARCH_USES_HIGH_VMA_FLAGS
2167	select ARCH_HAS_PKEYS
2168	help
2169	  The Permission Overlay Extension is used to implement Memory
2170	  Protection Keys. Memory Protection Keys provides a mechanism for
2171	  enforcing page-based protections, but without requiring modification
2172	  of the page tables when an application changes protection domains.
2173
2174	  For details, see Documentation/core-api/protection-keys.rst
2175
2176	  If unsure, say y.
2177
2178config ARCH_PKEY_BITS
2179	int
2180	default 3
2181
2182config ARM64_HAFT
2183	bool "Support for Hardware managed Access Flag for Table Descriptors"
2184	depends on ARM64_HW_AFDBM
2185	default y
2186	help
2187	  The ARMv8.9/ARMv9.5 introduces the feature Hardware managed Access
2188	  Flag for Table descriptors. When enabled an architectural executed
2189	  memory access will update the Access Flag in each Table descriptor
2190	  which is accessed during the translation table walk and for which
2191	  the Access Flag is 0. The Access Flag of the Table descriptor use
2192	  the same bit of PTE_AF.
2193
2194	  The feature will only be enabled if all the CPUs in the system
2195	  support this feature. If unsure, say Y.
2196
2197endmenu # "ARMv8.9 architectural features"
2198
2199menu "v9.4 architectural features"
2200
2201config ARM64_GCS
2202	bool "Enable support for Guarded Control Stack (GCS)"
2203	default y
2204	select ARCH_HAS_USER_SHADOW_STACK
2205	select ARCH_USES_HIGH_VMA_FLAGS
2206	depends on !UPROBES
2207	help
2208	  Guarded Control Stack (GCS) provides support for a separate
2209	  stack with restricted access which contains only return
2210	  addresses.  This can be used to harden against some attacks
2211	  by comparing return address used by the program with what is
2212	  stored in the GCS, and may also be used to efficiently obtain
2213	  the call stack for applications such as profiling.
2214
2215	  The feature is detected at runtime, and will remain disabled
2216	  if the system does not implement the feature.
2217
2218endmenu # "v9.4 architectural features"
2219
2220config ARM64_SVE
2221	bool "ARM Scalable Vector Extension support"
2222	default y
2223	help
2224	  The Scalable Vector Extension (SVE) is an extension to the AArch64
2225	  execution state which complements and extends the SIMD functionality
2226	  of the base architecture to support much larger vectors and to enable
2227	  additional vectorisation opportunities.
2228
2229	  To enable use of this extension on CPUs that implement it, say Y.
2230
2231	  On CPUs that support the SVE2 extensions, this option will enable
2232	  those too.
2233
2234	  Note that for architectural reasons, firmware _must_ implement SVE
2235	  support when running on SVE capable hardware.  The required support
2236	  is present in:
2237
2238	    * version 1.5 and later of the ARM Trusted Firmware
2239	    * the AArch64 boot wrapper since commit 5e1261e08abf
2240	      ("bootwrapper: SVE: Enable SVE for EL2 and below").
2241
2242	  For other firmware implementations, consult the firmware documentation
2243	  or vendor.
2244
2245	  If you need the kernel to boot on SVE-capable hardware with broken
2246	  firmware, you may need to say N here until you get your firmware
2247	  fixed.  Otherwise, you may experience firmware panics or lockups when
2248	  booting the kernel.  If unsure and you are not observing these
2249	  symptoms, you should assume that it is safe to say Y.
2250
2251config ARM64_SME
2252	bool "ARM Scalable Matrix Extension support"
2253	default y
2254	depends on ARM64_SVE
2255	depends on BROKEN
2256	help
2257	  The Scalable Matrix Extension (SME) is an extension to the AArch64
2258	  execution state which utilises a substantial subset of the SVE
2259	  instruction set, together with the addition of new architectural
2260	  register state capable of holding two dimensional matrix tiles to
2261	  enable various matrix operations.
2262
2263config ARM64_PSEUDO_NMI
2264	bool "Support for NMI-like interrupts"
2265	select ARM_GIC_V3
2266	help
2267	  Adds support for mimicking Non-Maskable Interrupts through the use of
2268	  GIC interrupt priority. This support requires version 3 or later of
2269	  ARM GIC.
2270
2271	  This high priority configuration for interrupts needs to be
2272	  explicitly enabled by setting the kernel parameter
2273	  "irqchip.gicv3_pseudo_nmi" to 1.
2274
2275	  If unsure, say N
2276
2277if ARM64_PSEUDO_NMI
2278config ARM64_DEBUG_PRIORITY_MASKING
2279	bool "Debug interrupt priority masking"
2280	help
2281	  This adds runtime checks to functions enabling/disabling
2282	  interrupts when using priority masking. The additional checks verify
2283	  the validity of ICC_PMR_EL1 when calling concerned functions.
2284
2285	  If unsure, say N
2286endif # ARM64_PSEUDO_NMI
2287
2288config RELOCATABLE
2289	bool "Build a relocatable kernel image" if EXPERT
2290	select ARCH_HAS_RELR
2291	default y
2292	help
2293	  This builds the kernel as a Position Independent Executable (PIE),
2294	  which retains all relocation metadata required to relocate the
2295	  kernel binary at runtime to a different virtual address than the
2296	  address it was linked at.
2297	  Since AArch64 uses the RELA relocation format, this requires a
2298	  relocation pass at runtime even if the kernel is loaded at the
2299	  same address it was linked at.
2300
2301config RANDOMIZE_BASE
2302	bool "Randomize the address of the kernel image"
2303	select RELOCATABLE
2304	help
2305	  Randomizes the virtual address at which the kernel image is
2306	  loaded, as a security feature that deters exploit attempts
2307	  relying on knowledge of the location of kernel internals.
2308
2309	  It is the bootloader's job to provide entropy, by passing a
2310	  random u64 value in /chosen/kaslr-seed at kernel entry.
2311
2312	  When booting via the UEFI stub, it will invoke the firmware's
2313	  EFI_RNG_PROTOCOL implementation (if available) to supply entropy
2314	  to the kernel proper. In addition, it will randomise the physical
2315	  location of the kernel Image as well.
2316
2317	  If unsure, say N.
2318
2319config RANDOMIZE_MODULE_REGION_FULL
2320	bool "Randomize the module region over a 2 GB range"
2321	depends on RANDOMIZE_BASE
2322	default y
2323	help
2324	  Randomizes the location of the module region inside a 2 GB window
2325	  covering the core kernel. This way, it is less likely for modules
2326	  to leak information about the location of core kernel data structures
2327	  but it does imply that function calls between modules and the core
2328	  kernel will need to be resolved via veneers in the module PLT.
2329
2330	  When this option is not set, the module region will be randomized over
2331	  a limited range that contains the [_stext, _etext] interval of the
2332	  core kernel, so branch relocations are almost always in range unless
2333	  the region is exhausted. In this particular case of region
2334	  exhaustion, modules might be able to fall back to a larger 2GB area.
2335
2336config CC_HAVE_STACKPROTECTOR_SYSREG
2337	def_bool $(cc-option,-mstack-protector-guard=sysreg -mstack-protector-guard-reg=sp_el0 -mstack-protector-guard-offset=0)
2338
2339config STACKPROTECTOR_PER_TASK
2340	def_bool y
2341	depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_SYSREG
2342
2343config UNWIND_PATCH_PAC_INTO_SCS
2344	bool "Enable shadow call stack dynamically using code patching"
2345	# needs Clang with https://github.com/llvm/llvm-project/commit/de07cde67b5d205d58690be012106022aea6d2b3 incorporated
2346	depends on CC_IS_CLANG && CLANG_VERSION >= 150000
2347	depends on ARM64_PTR_AUTH_KERNEL && CC_HAS_BRANCH_PROT_PAC_RET
2348	depends on SHADOW_CALL_STACK
2349	select UNWIND_TABLES
2350	select DYNAMIC_SCS
2351
2352config ARM64_CONTPTE
2353	bool "Contiguous PTE mappings for user memory" if EXPERT
2354	depends on TRANSPARENT_HUGEPAGE
2355	default y
2356	help
2357	  When enabled, user mappings are configured using the PTE contiguous
2358	  bit, for any mappings that meet the size and alignment requirements.
2359	  This reduces TLB pressure and improves performance.
2360
2361endmenu # "Kernel Features"
2362
2363menu "Boot options"
2364
2365config ARM64_ACPI_PARKING_PROTOCOL
2366	bool "Enable support for the ARM64 ACPI parking protocol"
2367	depends on ACPI
2368	help
2369	  Enable support for the ARM64 ACPI parking protocol. If disabled
2370	  the kernel will not allow booting through the ARM64 ACPI parking
2371	  protocol even if the corresponding data is present in the ACPI
2372	  MADT table.
2373
2374config CMDLINE
2375	string "Default kernel command string"
2376	default ""
2377	help
2378	  Provide a set of default command-line options at build time by
2379	  entering them here. As a minimum, you should specify the the
2380	  root device (e.g. root=/dev/nfs).
2381
2382choice
2383	prompt "Kernel command line type"
2384	depends on CMDLINE != ""
2385	default CMDLINE_FROM_BOOTLOADER
2386	help
2387	  Choose how the kernel will handle the provided default kernel
2388	  command line string.
2389
2390config CMDLINE_FROM_BOOTLOADER
2391	bool "Use bootloader kernel arguments if available"
2392	help
2393	  Uses the command-line options passed by the boot loader. If
2394	  the boot loader doesn't provide any, the default kernel command
2395	  string provided in CMDLINE will be used.
2396
2397config CMDLINE_FORCE
2398	bool "Always use the default kernel command string"
2399	help
2400	  Always use the default kernel command string, even if the boot
2401	  loader passes other arguments to the kernel.
2402	  This is useful if you cannot or don't want to change the
2403	  command-line options your boot loader passes to the kernel.
2404
2405endchoice
2406
2407config EFI_STUB
2408	bool
2409
2410config EFI
2411	bool "UEFI runtime support"
2412	depends on OF && !CPU_BIG_ENDIAN
2413	depends on KERNEL_MODE_NEON
2414	select ARCH_SUPPORTS_ACPI
2415	select LIBFDT
2416	select UCS2_STRING
2417	select EFI_PARAMS_FROM_FDT
2418	select EFI_RUNTIME_WRAPPERS
2419	select EFI_STUB
2420	select EFI_GENERIC_STUB
2421	imply IMA_SECURE_AND_OR_TRUSTED_BOOT
2422	default y
2423	help
2424	  This option provides support for runtime services provided
2425	  by UEFI firmware (such as non-volatile variables, realtime
2426	  clock, and platform reset). A UEFI stub is also provided to
2427	  allow the kernel to be booted as an EFI application. This
2428	  is only useful on systems that have UEFI firmware.
2429
2430config COMPRESSED_INSTALL
2431	bool "Install compressed image by default"
2432	help
2433	  This makes the regular "make install" install the compressed
2434	  image we built, not the legacy uncompressed one.
2435
2436	  You can check that a compressed image works for you by doing
2437	  "make zinstall" first, and verifying that everything is fine
2438	  in your environment before making "make install" do this for
2439	  you.
2440
2441config DMI
2442	bool "Enable support for SMBIOS (DMI) tables"
2443	depends on EFI
2444	default y
2445	help
2446	  This enables SMBIOS/DMI feature for systems.
2447
2448	  This option is only useful on systems that have UEFI firmware.
2449	  However, even with this option, the resultant kernel should
2450	  continue to boot on existing non-UEFI platforms.
2451
2452endmenu # "Boot options"
2453
2454menu "Power management options"
2455
2456source "kernel/power/Kconfig"
2457
2458config ARCH_HIBERNATION_POSSIBLE
2459	def_bool y
2460	depends on CPU_PM
2461
2462config ARCH_HIBERNATION_HEADER
2463	def_bool y
2464	depends on HIBERNATION
2465
2466config ARCH_SUSPEND_POSSIBLE
2467	def_bool y
2468
2469endmenu # "Power management options"
2470
2471menu "CPU Power Management"
2472
2473source "drivers/cpuidle/Kconfig"
2474
2475source "drivers/cpufreq/Kconfig"
2476
2477endmenu # "CPU Power Management"
2478
2479source "drivers/acpi/Kconfig"
2480
2481source "arch/arm64/kvm/Kconfig"
2482
2483