xref: /linux/arch/arm64/Kconfig (revision c574fb2ed7c96f87fc0e5295e910e646a7ee4dfa)
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_CURRENT_STACK_POINTER
25	select ARCH_HAS_DEBUG_VIRTUAL
26	select ARCH_HAS_DEBUG_VM_PGTABLE
27	select ARCH_HAS_DMA_OPS if XEN
28	select ARCH_HAS_DMA_PREP_COHERENT
29	select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI
30	select ARCH_HAS_FAST_MULTIPLIER
31	select ARCH_HAS_FORTIFY_SOURCE
32	select ARCH_HAS_GCOV_PROFILE_ALL
33	select ARCH_HAS_GIGANTIC_PAGE
34	select ARCH_HAS_KCOV
35	select ARCH_HAS_KERNEL_FPU_SUPPORT if KERNEL_MODE_NEON
36	select ARCH_HAS_KEEPINITRD
37	select ARCH_HAS_MEMBARRIER_SYNC_CORE
38	select ARCH_HAS_MEM_ENCRYPT
39	select ARCH_SUPPORTS_MSEAL_SYSTEM_MAPPINGS
40	select ARCH_HAS_NMI_SAFE_THIS_CPU_OPS
41	select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
42	select ARCH_HAS_NONLEAF_PMD_YOUNG if ARM64_HAFT
43	select ARCH_HAS_PREEMPT_LAZY
44	select ARCH_HAS_PTDUMP
45	select ARCH_HAS_PTE_SPECIAL
46	select ARCH_HAS_HW_PTE_YOUNG
47	select ARCH_HAS_SETUP_DMA_OPS
48	select ARCH_HAS_SET_DIRECT_MAP
49	select ARCH_HAS_SET_MEMORY
50	select ARCH_HAS_MEM_ENCRYPT
51	select ARCH_HAS_FORCE_DMA_UNENCRYPTED
52	select ARCH_STACKWALK
53	select ARCH_HAS_STRICT_KERNEL_RWX
54	select ARCH_HAS_STRICT_MODULE_RWX
55	select ARCH_HAS_SYNC_DMA_FOR_DEVICE
56	select ARCH_HAS_SYNC_DMA_FOR_CPU
57	select ARCH_HAS_SYSCALL_WRAPPER
58	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
59	select ARCH_HAS_ZONE_DMA_SET if EXPERT
60	select ARCH_HAVE_ELF_PROT
61	select ARCH_HAVE_NMI_SAFE_CMPXCHG
62	select ARCH_HAVE_TRACE_MMIO_ACCESS
63	select ARCH_INLINE_READ_LOCK if !PREEMPTION
64	select ARCH_INLINE_READ_LOCK_BH if !PREEMPTION
65	select ARCH_INLINE_READ_LOCK_IRQ if !PREEMPTION
66	select ARCH_INLINE_READ_LOCK_IRQSAVE if !PREEMPTION
67	select ARCH_INLINE_READ_UNLOCK if !PREEMPTION
68	select ARCH_INLINE_READ_UNLOCK_BH if !PREEMPTION
69	select ARCH_INLINE_READ_UNLOCK_IRQ if !PREEMPTION
70	select ARCH_INLINE_READ_UNLOCK_IRQRESTORE if !PREEMPTION
71	select ARCH_INLINE_WRITE_LOCK if !PREEMPTION
72	select ARCH_INLINE_WRITE_LOCK_BH if !PREEMPTION
73	select ARCH_INLINE_WRITE_LOCK_IRQ if !PREEMPTION
74	select ARCH_INLINE_WRITE_LOCK_IRQSAVE if !PREEMPTION
75	select ARCH_INLINE_WRITE_UNLOCK if !PREEMPTION
76	select ARCH_INLINE_WRITE_UNLOCK_BH if !PREEMPTION
77	select ARCH_INLINE_WRITE_UNLOCK_IRQ if !PREEMPTION
78	select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE if !PREEMPTION
79	select ARCH_INLINE_SPIN_TRYLOCK if !PREEMPTION
80	select ARCH_INLINE_SPIN_TRYLOCK_BH if !PREEMPTION
81	select ARCH_INLINE_SPIN_LOCK if !PREEMPTION
82	select ARCH_INLINE_SPIN_LOCK_BH if !PREEMPTION
83	select ARCH_INLINE_SPIN_LOCK_IRQ if !PREEMPTION
84	select ARCH_INLINE_SPIN_LOCK_IRQSAVE if !PREEMPTION
85	select ARCH_INLINE_SPIN_UNLOCK if !PREEMPTION
86	select ARCH_INLINE_SPIN_UNLOCK_BH if !PREEMPTION
87	select ARCH_INLINE_SPIN_UNLOCK_IRQ if !PREEMPTION
88	select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE if !PREEMPTION
89	select ARCH_KEEP_MEMBLOCK
90	select ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE
91	select ARCH_USE_CMPXCHG_LOCKREF
92	select ARCH_USE_GNU_PROPERTY
93	select ARCH_USE_MEMTEST
94	select ARCH_USE_QUEUED_RWLOCKS
95	select ARCH_USE_QUEUED_SPINLOCKS
96	select ARCH_USE_SYM_ANNOTATIONS
97	select ARCH_SUPPORTS_DEBUG_PAGEALLOC
98	select ARCH_SUPPORTS_HUGETLBFS
99	select ARCH_SUPPORTS_MEMORY_FAILURE
100	select ARCH_SUPPORTS_SHADOW_CALL_STACK if CC_HAVE_SHADOW_CALL_STACK
101	select ARCH_SUPPORTS_LTO_CLANG if CPU_LITTLE_ENDIAN
102	select ARCH_SUPPORTS_LTO_CLANG_THIN
103	select ARCH_SUPPORTS_CFI
104	select ARCH_SUPPORTS_ATOMIC_RMW
105	select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
106	select ARCH_SUPPORTS_NUMA_BALANCING
107	select ARCH_SUPPORTS_PAGE_TABLE_CHECK
108	select ARCH_SUPPORTS_PER_VMA_LOCK
109	select ARCH_SUPPORTS_HUGE_PFNMAP if TRANSPARENT_HUGEPAGE
110	select ARCH_SUPPORTS_RT
111	select ARCH_SUPPORTS_SCHED_SMT
112	select ARCH_SUPPORTS_SCHED_CLUSTER
113	select ARCH_SUPPORTS_SCHED_MC
114	select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
115	select ARCH_WANT_COMPAT_IPC_PARSE_VERSION if COMPAT
116	select ARCH_WANT_DEFAULT_BPF_JIT
117	select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT
118	select ARCH_WANT_FRAME_POINTERS
119	select ARCH_WANT_HUGE_PMD_SHARE if ARM64_4K_PAGES || (ARM64_16K_PAGES && !ARM64_VA_BITS_36)
120	select ARCH_WANT_LD_ORPHAN_WARN
121	select ARCH_WANTS_EXECMEM_LATE
122	select ARCH_WANTS_NO_INSTR
123	select ARCH_WANTS_THP_SWAP if ARM64_4K_PAGES
124	select ARCH_HAS_UBSAN
125	select ARM_AMBA
126	select ARM_ARCH_TIMER
127	select ARM_GIC
128	select AUDIT_ARCH_COMPAT_GENERIC
129	select ARM_GIC_V2M if PCI
130	select ARM_GIC_V3
131	select ARM_GIC_V3_ITS if PCI
132	select ARM_GIC_V5
133	select ARM_PSCI_FW
134	select BUILDTIME_TABLE_SORT
135	select CLONE_BACKWARDS
136	select COMMON_CLK
137	select CPU_PM if (SUSPEND || CPU_IDLE)
138	select CPUMASK_OFFSTACK if NR_CPUS > 256
139	select DCACHE_WORD_ACCESS
140	select HAVE_EXTRA_IPI_TRACEPOINTS
141	select DYNAMIC_FTRACE if FUNCTION_TRACER
142	select DMA_BOUNCE_UNALIGNED_KMALLOC
143	select DMA_DIRECT_REMAP
144	select EDAC_SUPPORT
145	select FRAME_POINTER
146	select FUNCTION_ALIGNMENT_4B
147	select FUNCTION_ALIGNMENT_8B if DYNAMIC_FTRACE_WITH_CALL_OPS
148	select GENERIC_ALLOCATOR
149	select GENERIC_ARCH_TOPOLOGY
150	select GENERIC_CLOCKEVENTS_BROADCAST
151	select GENERIC_CPU_AUTOPROBE
152	select GENERIC_CPU_DEVICES
153	select GENERIC_CPU_VULNERABILITIES
154	select GENERIC_EARLY_IOREMAP
155	select GENERIC_IDLE_POLL_SETUP
156	select GENERIC_IOREMAP
157	select GENERIC_IRQ_ENTRY
158	select GENERIC_IRQ_IPI
159	select GENERIC_IRQ_KEXEC_CLEAR_VM_FORWARD
160	select GENERIC_IRQ_PROBE
161	select GENERIC_IRQ_SHOW
162	select GENERIC_IRQ_SHOW_LEVEL
163	select GENERIC_LIB_DEVMEM_IS_ALLOWED
164	select GENERIC_PCI_IOMAP
165	select GENERIC_SCHED_CLOCK
166	select GENERIC_SMP_IDLE_THREAD
167	select GENERIC_TIME_VSYSCALL
168	select GENERIC_GETTIMEOFDAY
169	select GENERIC_VDSO_DATA_STORE
170	select GENERIC_VDSO_TIME_NS
171	select HARDIRQS_SW_RESEND
172	select HAS_IOPORT
173	select HAVE_MOVE_PMD
174	select HAVE_MOVE_PUD
175	select HAVE_PCI
176	select HAVE_ACPI_APEI if (ACPI && EFI)
177	select HAVE_ALIGNED_STRUCT_PAGE
178	select HAVE_ARCH_AUDITSYSCALL
179	select HAVE_ARCH_BITREVERSE
180	select HAVE_ARCH_COMPILER_H
181	select HAVE_ARCH_HUGE_VMALLOC
182	select HAVE_ARCH_HUGE_VMAP
183	select HAVE_ARCH_JUMP_LABEL
184	select HAVE_ARCH_JUMP_LABEL_RELATIVE
185	select HAVE_ARCH_KASAN
186	select HAVE_ARCH_KASAN_VMALLOC
187	select HAVE_ARCH_KASAN_SW_TAGS
188	select HAVE_ARCH_KASAN_HW_TAGS if ARM64_MTE
189	# Some instrumentation may be unsound, hence EXPERT
190	select HAVE_ARCH_KCSAN if EXPERT
191	select HAVE_ARCH_KFENCE
192	select HAVE_ARCH_KGDB
193	select HAVE_ARCH_KSTACK_ERASE
194	select HAVE_ARCH_MMAP_RND_BITS
195	select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT
196	select HAVE_ARCH_PREL32_RELOCATIONS
197	select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET
198	select HAVE_ARCH_SECCOMP_FILTER
199	select HAVE_ARCH_THREAD_STRUCT_WHITELIST
200	select HAVE_ARCH_TRACEHOOK
201	select HAVE_ARCH_TRANSPARENT_HUGEPAGE
202	select HAVE_ARCH_VMAP_STACK
203	select HAVE_ARM_SMCCC
204	select HAVE_ASM_MODVERSIONS
205	select HAVE_EBPF_JIT
206	select HAVE_C_RECORDMCOUNT
207	select HAVE_CMPXCHG_DOUBLE
208	select HAVE_CMPXCHG_LOCAL
209	select HAVE_CONTEXT_TRACKING_USER
210	select HAVE_DEBUG_KMEMLEAK
211	select HAVE_DMA_CONTIGUOUS
212	select HAVE_DYNAMIC_FTRACE
213	select HAVE_DYNAMIC_FTRACE_WITH_ARGS \
214		if (GCC_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS || \
215		    CLANG_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS)
216	select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS \
217		if DYNAMIC_FTRACE_WITH_ARGS && DYNAMIC_FTRACE_WITH_CALL_OPS
218	select HAVE_DYNAMIC_FTRACE_WITH_CALL_OPS \
219		if (DYNAMIC_FTRACE_WITH_ARGS && !CFI && \
220		    (CC_IS_CLANG || !CC_OPTIMIZE_FOR_SIZE))
221	select FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY \
222		if DYNAMIC_FTRACE_WITH_ARGS
223	select HAVE_SAMPLE_FTRACE_DIRECT
224	select HAVE_SAMPLE_FTRACE_DIRECT_MULTI
225	select HAVE_BUILDTIME_MCOUNT_SORT
226	select HAVE_EFFICIENT_UNALIGNED_ACCESS
227	select HAVE_GUP_FAST
228	select HAVE_FTRACE_GRAPH_FUNC
229	select HAVE_FUNCTION_TRACER
230	select HAVE_FUNCTION_ERROR_INJECTION
231	select HAVE_FUNCTION_GRAPH_FREGS
232	select HAVE_FUNCTION_GRAPH_TRACER
233	select HAVE_GCC_PLUGINS
234	select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && \
235		HW_PERF_EVENTS && HAVE_PERF_EVENTS_NMI
236	select HAVE_HW_BREAKPOINT if PERF_EVENTS
237	select HAVE_IOREMAP_PROT
238	select HAVE_IRQ_TIME_ACCOUNTING
239	select HAVE_LIVEPATCH
240	select HAVE_MOD_ARCH_SPECIFIC
241	select HAVE_NMI
242	select HAVE_PERF_EVENTS
243	select HAVE_PERF_EVENTS_NMI if ARM64_PSEUDO_NMI
244	select HAVE_PERF_REGS
245	select HAVE_PERF_USER_STACK_DUMP
246	select HAVE_PREEMPT_DYNAMIC_KEY
247	select HAVE_REGS_AND_STACK_ACCESS_API
248	select HAVE_RELIABLE_STACKTRACE
249	select HAVE_POSIX_CPU_TIMERS_TASK_WORK
250	select HAVE_FUNCTION_ARG_ACCESS_API
251	select MMU_GATHER_RCU_TABLE_FREE
252	select HAVE_RSEQ
253	select HAVE_RUST if RUSTC_SUPPORTS_ARM64
254	select HAVE_STACKPROTECTOR
255	select HAVE_SYSCALL_TRACEPOINTS
256	select HAVE_KPROBES
257	select HAVE_KRETPROBES
258	select HAVE_GENERIC_VDSO
259	select HOTPLUG_CORE_SYNC_DEAD if HOTPLUG_CPU
260	select HOTPLUG_SMT if HOTPLUG_CPU
261	select IRQ_DOMAIN
262	select IRQ_FORCED_THREADING
263	select JUMP_LABEL
264	select KASAN_VMALLOC if KASAN
265	select LOCK_MM_AND_FIND_VMA
266	select MODULES_USE_ELF_RELA
267	select NEED_DMA_MAP_STATE
268	select NEED_SG_DMA_LENGTH
269	select OF
270	select OF_EARLY_FLATTREE
271	select PCI_DOMAINS_GENERIC if PCI
272	select PCI_ECAM if (ACPI && PCI)
273	select PCI_SYSCALL if PCI
274	select POWER_RESET
275	select POWER_SUPPLY
276	select SPARSE_IRQ
277	select SWIOTLB
278	select SYSCTL_EXCEPTION_TRACE
279	select THREAD_INFO_IN_TASK
280	select HAVE_ARCH_USERFAULTFD_MINOR if USERFAULTFD
281	select HAVE_ARCH_USERFAULTFD_WP if USERFAULTFD
282	select TRACE_IRQFLAGS_SUPPORT
283	select TRACE_IRQFLAGS_NMI_SUPPORT
284	select HAVE_SOFTIRQ_ON_OWN_STACK
285	select USER_STACKTRACE_SUPPORT
286	select VDSO_GETRANDOM
287	select VMAP_STACK
288	help
289	  ARM 64-bit (AArch64) Linux support.
290
291config RUSTC_SUPPORTS_ARM64
292	def_bool y
293	depends on CPU_LITTLE_ENDIAN
294	# Shadow call stack is only supported on certain rustc versions.
295	#
296	# When using the UNWIND_PATCH_PAC_INTO_SCS option, rustc version 1.80+ is
297	# required due to use of the -Zfixed-x18 flag.
298	#
299	# Otherwise, rustc version 1.82+ is required due to use of the
300	# -Zsanitizer=shadow-call-stack flag.
301	depends on !SHADOW_CALL_STACK || RUSTC_VERSION >= 108200 || RUSTC_VERSION >= 108000 && UNWIND_PATCH_PAC_INTO_SCS
302
303config CLANG_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS
304	def_bool CC_IS_CLANG
305	# https://github.com/ClangBuiltLinux/linux/issues/1507
306	depends on AS_IS_GNU || (AS_IS_LLVM && (LD_IS_LLD || LD_VERSION >= 23600))
307
308config GCC_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS
309	def_bool CC_IS_GCC
310	depends on $(cc-option,-fpatchable-function-entry=2)
311
312config 64BIT
313	def_bool y
314
315config MMU
316	def_bool y
317
318config ARM64_CONT_PTE_SHIFT
319	int
320	default 5 if PAGE_SIZE_64KB
321	default 7 if PAGE_SIZE_16KB
322	default 4
323
324config ARM64_CONT_PMD_SHIFT
325	int
326	default 5 if PAGE_SIZE_64KB
327	default 5 if PAGE_SIZE_16KB
328	default 4
329
330config ARCH_MMAP_RND_BITS_MIN
331	default 14 if PAGE_SIZE_64KB
332	default 16 if PAGE_SIZE_16KB
333	default 18
334
335# max bits determined by the following formula:
336#  VA_BITS - PTDESC_TABLE_SHIFT
337config ARCH_MMAP_RND_BITS_MAX
338	default 19 if ARM64_VA_BITS=36
339	default 24 if ARM64_VA_BITS=39
340	default 27 if ARM64_VA_BITS=42
341	default 30 if ARM64_VA_BITS=47
342	default 29 if (ARM64_VA_BITS=48 || ARM64_VA_BITS=52) && ARM64_64K_PAGES
343	default 31 if (ARM64_VA_BITS=48 || ARM64_VA_BITS=52) && ARM64_16K_PAGES
344	default 33 if (ARM64_VA_BITS=48 || ARM64_VA_BITS=52)
345	default 14 if ARM64_64K_PAGES
346	default 16 if ARM64_16K_PAGES
347	default 18
348
349config ARCH_MMAP_RND_COMPAT_BITS_MIN
350	default 7 if ARM64_64K_PAGES
351	default 9 if ARM64_16K_PAGES
352	default 11
353
354config ARCH_MMAP_RND_COMPAT_BITS_MAX
355	default 16
356
357config NO_IOPORT_MAP
358	def_bool y if !PCI
359
360config STACKTRACE_SUPPORT
361	def_bool y
362
363config ILLEGAL_POINTER_VALUE
364	hex
365	default 0xdead000000000000
366
367config LOCKDEP_SUPPORT
368	def_bool y
369
370config GENERIC_BUG
371	def_bool y
372	depends on BUG
373
374config GENERIC_BUG_RELATIVE_POINTERS
375	def_bool y
376	depends on GENERIC_BUG
377
378config GENERIC_HWEIGHT
379	def_bool y
380
381config GENERIC_CSUM
382	def_bool y
383
384config GENERIC_CALIBRATE_DELAY
385	def_bool y
386
387config SMP
388	def_bool y
389
390config KERNEL_MODE_NEON
391	def_bool y
392
393config FIX_EARLYCON_MEM
394	def_bool y
395
396config PGTABLE_LEVELS
397	int
398	default 2 if ARM64_16K_PAGES && ARM64_VA_BITS_36
399	default 2 if ARM64_64K_PAGES && ARM64_VA_BITS_42
400	default 3 if ARM64_64K_PAGES && (ARM64_VA_BITS_48 || ARM64_VA_BITS_52)
401	default 3 if ARM64_4K_PAGES && ARM64_VA_BITS_39
402	default 3 if ARM64_16K_PAGES && ARM64_VA_BITS_47
403	default 4 if ARM64_16K_PAGES && (ARM64_VA_BITS_48 || ARM64_VA_BITS_52)
404	default 4 if !ARM64_64K_PAGES && ARM64_VA_BITS_48
405	default 5 if ARM64_4K_PAGES && ARM64_VA_BITS_52
406
407config ARCH_SUPPORTS_UPROBES
408	def_bool y
409
410config ARCH_PROC_KCORE_TEXT
411	def_bool y
412
413config BROKEN_GAS_INST
414	def_bool !$(as-instr,1:\n.inst 0\n.rept . - 1b\n\nnop\n.endr\n)
415
416config BUILTIN_RETURN_ADDRESS_STRIPS_PAC
417	bool
418	# Clang's __builtin_return_address() strips the PAC since 12.0.0
419	# https://github.com/llvm/llvm-project/commit/2a96f47c5ffca84cd774ad402cacd137f4bf45e2
420	default y if CC_IS_CLANG
421	# GCC's __builtin_return_address() strips the PAC since 11.1.0,
422	# and this was backported to 10.2.0, 9.4.0, 8.5.0, but not earlier
423	# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94891
424	default y if CC_IS_GCC && (GCC_VERSION >= 110100)
425	default y if CC_IS_GCC && (GCC_VERSION >= 100200) && (GCC_VERSION < 110000)
426	default y if CC_IS_GCC && (GCC_VERSION >=  90400) && (GCC_VERSION < 100000)
427	default y if CC_IS_GCC && (GCC_VERSION >=  80500) && (GCC_VERSION <  90000)
428	default n
429
430config KASAN_SHADOW_OFFSET
431	hex
432	depends on KASAN_GENERIC || KASAN_SW_TAGS
433	default 0xdfff800000000000 if (ARM64_VA_BITS_48 || (ARM64_VA_BITS_52 && !ARM64_16K_PAGES)) && !KASAN_SW_TAGS
434	default 0xdfffc00000000000 if (ARM64_VA_BITS_47 || ARM64_VA_BITS_52) && ARM64_16K_PAGES && !KASAN_SW_TAGS
435	default 0xdffffe0000000000 if ARM64_VA_BITS_42 && !KASAN_SW_TAGS
436	default 0xdfffffc000000000 if ARM64_VA_BITS_39 && !KASAN_SW_TAGS
437	default 0xdffffff800000000 if ARM64_VA_BITS_36 && !KASAN_SW_TAGS
438	default 0xefff800000000000 if (ARM64_VA_BITS_48 || (ARM64_VA_BITS_52 && !ARM64_16K_PAGES)) && KASAN_SW_TAGS
439	default 0xefffc00000000000 if (ARM64_VA_BITS_47 || ARM64_VA_BITS_52) && ARM64_16K_PAGES && KASAN_SW_TAGS
440	default 0xeffffe0000000000 if ARM64_VA_BITS_42 && KASAN_SW_TAGS
441	default 0xefffffc000000000 if ARM64_VA_BITS_39 && KASAN_SW_TAGS
442	default 0xeffffff800000000 if ARM64_VA_BITS_36 && KASAN_SW_TAGS
443	default 0xffffffffffffffff
444
445config UNWIND_TABLES
446	bool
447
448source "arch/arm64/Kconfig.platforms"
449
450menu "Kernel Features"
451
452menu "ARM errata workarounds via the alternatives framework"
453
454config AMPERE_ERRATUM_AC03_CPU_38
455        bool "AmpereOne: AC03_CPU_38: Certain bits in the Virtualization Translation Control Register and Translation Control Registers do not follow RES0 semantics"
456	default y
457	help
458	  This option adds an alternative code sequence to work around Ampere
459	  errata AC03_CPU_38 and AC04_CPU_10 on AmpereOne.
460
461	  The affected design reports FEAT_HAFDBS as not implemented in
462	  ID_AA64MMFR1_EL1.HAFDBS, but (V)TCR_ELx.{HA,HD} are not RES0
463	  as required by the architecture. The unadvertised HAFDBS
464	  implementation suffers from an additional erratum where hardware
465	  A/D updates can occur after a PTE has been marked invalid.
466
467	  The workaround forces KVM to explicitly set VTCR_EL2.HA to 0,
468	  which avoids enabling unadvertised hardware Access Flag management
469	  at stage-2.
470
471	  If unsure, say Y.
472
473config AMPERE_ERRATUM_AC04_CPU_23
474        bool "AmpereOne: AC04_CPU_23:  Failure to synchronize writes to HCR_EL2 may corrupt address translations."
475	default y
476	help
477	  This option adds an alternative code sequence to work around Ampere
478	  errata AC04_CPU_23 on AmpereOne.
479
480	  Updates to HCR_EL2 can rarely corrupt simultaneous translations for
481	  data addresses initiated by load/store instructions. Only
482	  instruction initiated translations are vulnerable, not translations
483	  from prefetches for example. A DSB before the store to HCR_EL2 is
484	  sufficient to prevent older instructions from hitting the window
485	  for corruption, and an ISB after is sufficient to prevent younger
486	  instructions from hitting the window for corruption.
487
488	  If unsure, say Y.
489
490config ARM64_WORKAROUND_CLEAN_CACHE
491	bool
492
493config ARM64_ERRATUM_826319
494	bool "Cortex-A53: 826319: System might deadlock if a write cannot complete until read data is accepted"
495	default y
496	select ARM64_WORKAROUND_CLEAN_CACHE
497	help
498	  This option adds an alternative code sequence to work around ARM
499	  erratum 826319 on Cortex-A53 parts up to r0p2 with an AMBA 4 ACE or
500	  AXI master interface and an L2 cache.
501
502	  If a Cortex-A53 uses an AMBA AXI4 ACE interface to other processors
503	  and is unable to accept a certain write via this interface, it will
504	  not progress on read data presented on the read data channel and the
505	  system can deadlock.
506
507	  The workaround promotes data cache clean instructions to
508	  data cache clean-and-invalidate.
509	  Please note that this does not necessarily enable the workaround,
510	  as it depends on the alternative framework, which will only patch
511	  the kernel if an affected CPU is detected.
512
513	  If unsure, say Y.
514
515config ARM64_ERRATUM_827319
516	bool "Cortex-A53: 827319: Data cache clean instructions might cause overlapping transactions to the interconnect"
517	default y
518	select ARM64_WORKAROUND_CLEAN_CACHE
519	help
520	  This option adds an alternative code sequence to work around ARM
521	  erratum 827319 on Cortex-A53 parts up to r0p2 with an AMBA 5 CHI
522	  master interface and an L2 cache.
523
524	  Under certain conditions this erratum can cause a clean line eviction
525	  to occur at the same time as another transaction to the same address
526	  on the AMBA 5 CHI interface, which can cause data corruption if the
527	  interconnect reorders the two transactions.
528
529	  The workaround promotes data cache clean instructions to
530	  data cache clean-and-invalidate.
531	  Please note that this does not necessarily enable the workaround,
532	  as it depends on the alternative framework, which will only patch
533	  the kernel if an affected CPU is detected.
534
535	  If unsure, say Y.
536
537config ARM64_ERRATUM_824069
538	bool "Cortex-A53: 824069: Cache line might not be marked as clean after a CleanShared snoop"
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 824069 on Cortex-A53 parts up to r0p2 when it is connected
544	  to a coherent interconnect.
545
546	  If a Cortex-A53 processor is executing a store or prefetch for
547	  write instruction at the same time as a processor in another
548	  cluster is executing a cache maintenance operation to the same
549	  address, then this erratum might cause a clean cache line to be
550	  incorrectly marked as dirty.
551
552	  The workaround promotes data cache clean instructions to
553	  data cache clean-and-invalidate.
554	  Please note that this option does not necessarily enable the
555	  workaround, as it depends on the alternative framework, which will
556	  only patch the kernel if an affected CPU is detected.
557
558	  If unsure, say Y.
559
560config ARM64_ERRATUM_819472
561	bool "Cortex-A53: 819472: Store exclusive instructions might cause data corruption"
562	default y
563	select ARM64_WORKAROUND_CLEAN_CACHE
564	help
565	  This option adds an alternative code sequence to work around ARM
566	  erratum 819472 on Cortex-A53 parts up to r0p1 with an L2 cache
567	  present when it is connected to a coherent interconnect.
568
569	  If the processor is executing a load and store exclusive sequence at
570	  the same time as a processor in another cluster is executing a cache
571	  maintenance operation to the same address, then this erratum might
572	  cause data corruption.
573
574	  The workaround promotes data cache clean instructions to
575	  data cache clean-and-invalidate.
576	  Please note that this does not necessarily enable the workaround,
577	  as it depends on the alternative framework, which will only patch
578	  the kernel if an affected CPU is detected.
579
580	  If unsure, say Y.
581
582config ARM64_ERRATUM_832075
583	bool "Cortex-A57: 832075: possible deadlock on mixing exclusive memory accesses with device loads"
584	default y
585	help
586	  This option adds an alternative code sequence to work around ARM
587	  erratum 832075 on Cortex-A57 parts up to r1p2.
588
589	  Affected Cortex-A57 parts might deadlock when exclusive load/store
590	  instructions to Write-Back memory are mixed with Device loads.
591
592	  The workaround is to promote device loads to use Load-Acquire
593	  semantics.
594	  Please note that this does not necessarily enable the workaround,
595	  as it depends on the alternative framework, which will only patch
596	  the kernel if an affected CPU is detected.
597
598	  If unsure, say Y.
599
600config ARM64_ERRATUM_834220
601	bool "Cortex-A57: 834220: Stage 2 translation fault might be incorrectly reported in presence of a Stage 1 fault (rare)"
602	depends on KVM
603	help
604	  This option adds an alternative code sequence to work around ARM
605	  erratum 834220 on Cortex-A57 parts up to r1p2.
606
607	  Affected Cortex-A57 parts might report a Stage 2 translation
608	  fault as the result of a Stage 1 fault for load crossing a
609	  page boundary when there is a permission or device memory
610	  alignment fault at Stage 1 and a translation fault at Stage 2.
611
612	  The workaround is to verify that the Stage 1 translation
613	  doesn't generate a fault before handling the Stage 2 fault.
614	  Please note that this does not necessarily enable the workaround,
615	  as it depends on the alternative framework, which will only patch
616	  the kernel if an affected CPU is detected.
617
618	  If unsure, say N.
619
620config ARM64_ERRATUM_1742098
621	bool "Cortex-A57/A72: 1742098: ELR recorded incorrectly on interrupt taken between cryptographic instructions in a sequence"
622	depends on COMPAT
623	default y
624	help
625	  This option removes the AES hwcap for aarch32 user-space to
626	  workaround erratum 1742098 on Cortex-A57 and Cortex-A72.
627
628	  Affected parts may corrupt the AES state if an interrupt is
629	  taken between a pair of AES instructions. These instructions
630	  are only present if the cryptography extensions are present.
631	  All software should have a fallback implementation for CPUs
632	  that don't implement the cryptography extensions.
633
634	  If unsure, say Y.
635
636config ARM64_ERRATUM_845719
637	bool "Cortex-A53: 845719: a load might read incorrect data"
638	depends on COMPAT
639	default y
640	help
641	  This option adds an alternative code sequence to work around ARM
642	  erratum 845719 on Cortex-A53 parts up to r0p4.
643
644	  When running a compat (AArch32) userspace on an affected Cortex-A53
645	  part, a load at EL0 from a virtual address that matches the bottom 32
646	  bits of the virtual address used by a recent load at (AArch64) EL1
647	  might return incorrect data.
648
649	  The workaround is to write the contextidr_el1 register on exception
650	  return to a 32-bit task.
651	  Please note that this does not necessarily enable the workaround,
652	  as it depends on the alternative framework, which will only patch
653	  the kernel if an affected CPU is detected.
654
655	  If unsure, say Y.
656
657config ARM64_ERRATUM_843419
658	bool "Cortex-A53: 843419: A load or store might access an incorrect address"
659	default y
660	help
661	  This option links the kernel with '--fix-cortex-a53-843419' and
662	  enables PLT support to replace certain ADRP instructions, which can
663	  cause subsequent memory accesses to use an incorrect address on
664	  Cortex-A53 parts up to r0p4.
665
666	  If unsure, say Y.
667
668config ARM64_ERRATUM_1024718
669	bool "Cortex-A55: 1024718: Update of DBM/AP bits without break before make might result in incorrect update"
670	default y
671	help
672	  This option adds a workaround for ARM Cortex-A55 Erratum 1024718.
673
674	  Affected Cortex-A55 cores (all revisions) could cause incorrect
675	  update of the hardware dirty bit when the DBM/AP bits are updated
676	  without a break-before-make. The workaround is to disable the usage
677	  of hardware DBM locally on the affected cores. CPUs not affected by
678	  this erratum will continue to use the feature.
679
680	  If unsure, say Y.
681
682config ARM64_ERRATUM_1418040
683	bool "Cortex-A76/Neoverse-N1: MRC read following MRRC read of specific Generic Timer in AArch32 might give incorrect result"
684	default y
685	depends on COMPAT
686	help
687	  This option adds a workaround for ARM Cortex-A76/Neoverse-N1
688	  errata 1188873 and 1418040.
689
690	  Affected Cortex-A76/Neoverse-N1 cores (r0p0 to r3p1) could
691	  cause register corruption when accessing the timer registers
692	  from AArch32 userspace.
693
694	  If unsure, say Y.
695
696config ARM64_WORKAROUND_SPECULATIVE_AT
697	bool
698
699config ARM64_ERRATUM_1165522
700	bool "Cortex-A76: 1165522: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
701	default y
702	select ARM64_WORKAROUND_SPECULATIVE_AT
703	help
704	  This option adds a workaround for ARM Cortex-A76 erratum 1165522.
705
706	  Affected Cortex-A76 cores (r0p0, r1p0, r2p0) could end-up with
707	  corrupted TLBs by speculating an AT instruction during a guest
708	  context switch.
709
710	  If unsure, say Y.
711
712config ARM64_ERRATUM_1319367
713	bool "Cortex-A57/A72: 1319537: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
714	default y
715	select ARM64_WORKAROUND_SPECULATIVE_AT
716	help
717	  This option adds work arounds for ARM Cortex-A57 erratum 1319537
718	  and A72 erratum 1319367
719
720	  Cortex-A57 and A72 cores could end-up with corrupted TLBs by
721	  speculating an AT instruction during a guest context switch.
722
723	  If unsure, say Y.
724
725config ARM64_ERRATUM_1530923
726	bool "Cortex-A55: 1530923: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
727	default y
728	select ARM64_WORKAROUND_SPECULATIVE_AT
729	help
730	  This option adds a workaround for ARM Cortex-A55 erratum 1530923.
731
732	  Affected Cortex-A55 cores (r0p0, r0p1, r1p0, r2p0) could end-up with
733	  corrupted TLBs by speculating an AT instruction during a guest
734	  context switch.
735
736	  If unsure, say Y.
737
738config ARM64_WORKAROUND_REPEAT_TLBI
739	bool
740
741config ARM64_ERRATUM_2441007
742	bool "Cortex-A55: Completion of affected memory accesses might not be guaranteed by completion of a TLBI (rare)"
743	select ARM64_WORKAROUND_REPEAT_TLBI
744	help
745	  This option adds a workaround for ARM Cortex-A55 erratum #2441007.
746
747	  Under very rare circumstances, affected Cortex-A55 CPUs
748	  may not handle a race between a break-before-make sequence on one
749	  CPU, and another CPU accessing the same page. This could allow a
750	  store to a page that has been unmapped.
751
752	  Work around this by adding the affected CPUs to the list that needs
753	  TLB sequences to be done twice.
754
755	  If unsure, say N.
756
757config ARM64_ERRATUM_1286807
758	bool "Cortex-A76: Modification of the translation table for a virtual address might lead to read-after-read ordering violation (rare)"
759	select ARM64_WORKAROUND_REPEAT_TLBI
760	help
761	  This option adds a workaround for ARM Cortex-A76 erratum 1286807.
762
763	  On the affected Cortex-A76 cores (r0p0 to r3p0), if a virtual
764	  address for a cacheable mapping of a location is being
765	  accessed by a core while another core is remapping the virtual
766	  address to a new physical page using the recommended
767	  break-before-make sequence, then under very rare circumstances
768	  TLBI+DSB completes before a read using the translation being
769	  invalidated has been observed by other observers. The
770	  workaround repeats the TLBI+DSB operation.
771
772	  If unsure, say N.
773
774config ARM64_ERRATUM_1463225
775	bool "Cortex-A76: Software Step might prevent interrupt recognition"
776	default y
777	help
778	  This option adds a workaround for Arm Cortex-A76 erratum 1463225.
779
780	  On the affected Cortex-A76 cores (r0p0 to r3p1), software stepping
781	  of a system call instruction (SVC) can prevent recognition of
782	  subsequent interrupts when software stepping is disabled in the
783	  exception handler of the system call and either kernel debugging
784	  is enabled or VHE is in use.
785
786	  Work around the erratum by triggering a dummy step exception
787	  when handling a system call from a task that is being stepped
788	  in a VHE configuration of the kernel.
789
790	  If unsure, say Y.
791
792config ARM64_ERRATUM_1542419
793	bool "Neoverse-N1: workaround mis-ordering of instruction fetches (rare)"
794	help
795	  This option adds a workaround for ARM Neoverse-N1 erratum
796	  1542419.
797
798	  Affected Neoverse-N1 cores could execute a stale instruction when
799	  modified by another CPU. The workaround depends on a firmware
800	  counterpart.
801
802	  Workaround the issue by hiding the DIC feature from EL0. This
803	  forces user-space to perform cache maintenance.
804
805	  If unsure, say N.
806
807config ARM64_ERRATUM_1508412
808	bool "Cortex-A77: 1508412: workaround deadlock on sequence of NC/Device load and store exclusive or PAR read"
809	default y
810	help
811	  This option adds a workaround for Arm Cortex-A77 erratum 1508412.
812
813	  Affected Cortex-A77 cores (r0p0, r1p0) could deadlock on a sequence
814	  of a store-exclusive or read of PAR_EL1 and a load with device or
815	  non-cacheable memory attributes. The workaround depends on a firmware
816	  counterpart.
817
818	  KVM guests must also have the workaround implemented or they can
819	  deadlock the system.
820
821	  Work around the issue by inserting DMB SY barriers around PAR_EL1
822	  register reads and warning KVM users. The DMB barrier is sufficient
823	  to prevent a speculative PAR_EL1 read.
824
825	  If unsure, say Y.
826
827config ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
828	bool
829
830config ARM64_ERRATUM_2051678
831	bool "Cortex-A510: 2051678: disable Hardware Update of the page table dirty bit"
832	default y
833	help
834	  This options adds the workaround for ARM Cortex-A510 erratum ARM64_ERRATUM_2051678.
835	  Affected Cortex-A510 might not respect the ordering rules for
836	  hardware update of the page table's dirty bit. The workaround
837	  is to not enable the feature on affected CPUs.
838
839	  If unsure, say Y.
840
841config ARM64_ERRATUM_2077057
842	bool "Cortex-A510: 2077057: workaround software-step corrupting SPSR_EL2"
843	default y
844	help
845	  This option adds the workaround for ARM Cortex-A510 erratum 2077057.
846	  Affected Cortex-A510 may corrupt SPSR_EL2 when the a step exception is
847	  expected, but a Pointer Authentication trap is taken instead. The
848	  erratum causes SPSR_EL1 to be copied to SPSR_EL2, which could allow
849	  EL1 to cause a return to EL2 with a guest controlled ELR_EL2.
850
851	  This can only happen when EL2 is stepping EL1.
852
853	  When these conditions occur, the SPSR_EL2 value is unchanged from the
854	  previous guest entry, and can be restored from the in-memory copy.
855
856	  If unsure, say Y.
857
858config ARM64_ERRATUM_2658417
859	bool "Cortex-A510: 2658417: remove BF16 support due to incorrect result"
860	default y
861	help
862	  This option adds the workaround for ARM Cortex-A510 erratum 2658417.
863	  Affected Cortex-A510 (r0p0 to r1p1) may produce the wrong result for
864	  BFMMLA or VMMLA instructions in rare circumstances when a pair of
865	  A510 CPUs are using shared neon hardware. As the sharing is not
866	  discoverable by the kernel, hide the BF16 HWCAP to indicate that
867	  user-space should not be using these instructions.
868
869	  If unsure, say Y.
870
871config ARM64_ERRATUM_2119858
872	bool "Cortex-A710/X2: 2119858: workaround TRBE overwriting trace data in FILL mode"
873	default y
874	depends on CORESIGHT_TRBE
875	select ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
876	help
877	  This option adds the workaround for ARM Cortex-A710/X2 erratum 2119858.
878
879	  Affected Cortex-A710/X2 cores could overwrite up to 3 cache lines of trace
880	  data at the base of the buffer (pointed to by TRBASER_EL1) in FILL mode in
881	  the event of a WRAP event.
882
883	  Work around the issue by always making sure we move the TRBPTR_EL1 by
884	  256 bytes before enabling the buffer and filling the first 256 bytes of
885	  the buffer with ETM ignore packets upon disabling.
886
887	  If unsure, say Y.
888
889config ARM64_ERRATUM_2139208
890	bool "Neoverse-N2: 2139208: workaround TRBE overwriting trace data in FILL mode"
891	default y
892	depends on CORESIGHT_TRBE
893	select ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
894	help
895	  This option adds the workaround for ARM Neoverse-N2 erratum 2139208.
896
897	  Affected Neoverse-N2 cores could overwrite up to 3 cache lines of trace
898	  data at the base of the buffer (pointed to by TRBASER_EL1) in FILL mode in
899	  the event of a WRAP event.
900
901	  Work around the issue by always making sure we move the TRBPTR_EL1 by
902	  256 bytes before enabling the buffer and filling the first 256 bytes of
903	  the buffer with ETM ignore packets upon disabling.
904
905	  If unsure, say Y.
906
907config ARM64_WORKAROUND_TSB_FLUSH_FAILURE
908	bool
909
910config ARM64_ERRATUM_2054223
911	bool "Cortex-A710: 2054223: workaround TSB instruction failing to flush trace"
912	default y
913	select ARM64_WORKAROUND_TSB_FLUSH_FAILURE
914	help
915	  Enable workaround for ARM Cortex-A710 erratum 2054223
916
917	  Affected cores may fail to flush the trace data on a TSB instruction, when
918	  the PE is in trace prohibited state. This will cause losing a few bytes
919	  of the trace cached.
920
921	  Workaround is to issue two TSB consecutively on affected cores.
922
923	  If unsure, say Y.
924
925config ARM64_ERRATUM_2067961
926	bool "Neoverse-N2: 2067961: workaround TSB instruction failing to flush trace"
927	default y
928	select ARM64_WORKAROUND_TSB_FLUSH_FAILURE
929	help
930	  Enable workaround for ARM Neoverse-N2 erratum 2067961
931
932	  Affected cores may fail to flush the trace data on a TSB instruction, when
933	  the PE is in trace prohibited state. This will cause losing a few bytes
934	  of the trace cached.
935
936	  Workaround is to issue two TSB consecutively on affected cores.
937
938	  If unsure, say Y.
939
940config ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE
941	bool
942
943config ARM64_ERRATUM_2253138
944	bool "Neoverse-N2: 2253138: workaround TRBE writing to address out-of-range"
945	depends on CORESIGHT_TRBE
946	default y
947	select ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE
948	help
949	  This option adds the workaround for ARM Neoverse-N2 erratum 2253138.
950
951	  Affected Neoverse-N2 cores might write to an out-of-range address, not reserved
952	  for TRBE. Under some conditions, the TRBE might generate a write to the next
953	  virtually addressed page following the last page of the TRBE address space
954	  (i.e., the TRBLIMITR_EL1.LIMIT), instead of wrapping around to the base.
955
956	  Work around this in the driver by always making sure that there is a
957	  page beyond the TRBLIMITR_EL1.LIMIT, within the space allowed for the TRBE.
958
959	  If unsure, say Y.
960
961config ARM64_ERRATUM_2224489
962	bool "Cortex-A710/X2: 2224489: workaround TRBE writing to address out-of-range"
963	depends on CORESIGHT_TRBE
964	default y
965	select ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE
966	help
967	  This option adds the workaround for ARM Cortex-A710/X2 erratum 2224489.
968
969	  Affected Cortex-A710/X2 cores might write to an out-of-range address, not reserved
970	  for TRBE. Under some conditions, the TRBE might generate a write to the next
971	  virtually addressed page following the last page of the TRBE address space
972	  (i.e., the TRBLIMITR_EL1.LIMIT), instead of wrapping around to the base.
973
974	  Work around this in the driver by always making sure that there is a
975	  page beyond the TRBLIMITR_EL1.LIMIT, within the space allowed for the TRBE.
976
977	  If unsure, say Y.
978
979config ARM64_ERRATUM_2441009
980	bool "Cortex-A510: Completion of affected memory accesses might not be guaranteed by completion of a TLBI (rare)"
981	select ARM64_WORKAROUND_REPEAT_TLBI
982	help
983	  This option adds a workaround for ARM Cortex-A510 erratum #2441009.
984
985	  Under very rare circumstances, affected Cortex-A510 CPUs
986	  may not handle a race between a break-before-make sequence on one
987	  CPU, and another CPU accessing the same page. This could allow a
988	  store to a page that has been unmapped.
989
990	  Work around this by adding the affected CPUs to the list that needs
991	  TLB sequences to be done twice.
992
993	  If unsure, say N.
994
995config ARM64_ERRATUM_2064142
996	bool "Cortex-A510: 2064142: workaround TRBE register writes while disabled"
997	depends on CORESIGHT_TRBE
998	default y
999	help
1000	  This option adds the workaround for ARM Cortex-A510 erratum 2064142.
1001
1002	  Affected Cortex-A510 core might fail to write into system registers after the
1003	  TRBE has been disabled. Under some conditions after the TRBE has been disabled
1004	  writes into TRBE registers TRBLIMITR_EL1, TRBPTR_EL1, TRBBASER_EL1, TRBSR_EL1,
1005	  and TRBTRG_EL1 will be ignored and will not be effected.
1006
1007	  Work around this in the driver by executing TSB CSYNC and DSB after collection
1008	  is stopped and before performing a system register write to one of the affected
1009	  registers.
1010
1011	  If unsure, say Y.
1012
1013config ARM64_ERRATUM_2038923
1014	bool "Cortex-A510: 2038923: workaround TRBE corruption with enable"
1015	depends on CORESIGHT_TRBE
1016	default y
1017	help
1018	  This option adds the workaround for ARM Cortex-A510 erratum 2038923.
1019
1020	  Affected Cortex-A510 core might cause an inconsistent view on whether trace is
1021	  prohibited within the CPU. As a result, the trace buffer or trace buffer state
1022	  might be corrupted. This happens after TRBE buffer has been enabled by setting
1023	  TRBLIMITR_EL1.E, followed by just a single context synchronization event before
1024	  execution changes from a context, in which trace is prohibited to one where it
1025	  isn't, or vice versa. In these mentioned conditions, the view of whether trace
1026	  is prohibited is inconsistent between parts of the CPU, and the trace buffer or
1027	  the trace buffer state might be corrupted.
1028
1029	  Work around this in the driver by preventing an inconsistent view of whether the
1030	  trace is prohibited or not based on TRBLIMITR_EL1.E by immediately following a
1031	  change to TRBLIMITR_EL1.E with at least one ISB instruction before an ERET, or
1032	  two ISB instructions if no ERET is to take place.
1033
1034	  If unsure, say Y.
1035
1036config ARM64_ERRATUM_1902691
1037	bool "Cortex-A510: 1902691: workaround TRBE trace corruption"
1038	depends on CORESIGHT_TRBE
1039	default y
1040	help
1041	  This option adds the workaround for ARM Cortex-A510 erratum 1902691.
1042
1043	  Affected Cortex-A510 core might cause trace data corruption, when being written
1044	  into the memory. Effectively TRBE is broken and hence cannot be used to capture
1045	  trace data.
1046
1047	  Work around this problem in the driver by just preventing TRBE initialization on
1048	  affected cpus. The firmware must have disabled the access to TRBE for the kernel
1049	  on such implementations. This will cover the kernel for any firmware that doesn't
1050	  do this already.
1051
1052	  If unsure, say Y.
1053
1054config ARM64_ERRATUM_2457168
1055	bool "Cortex-A510: 2457168: workaround for AMEVCNTR01 incrementing incorrectly"
1056	depends on ARM64_AMU_EXTN
1057	default y
1058	help
1059	  This option adds the workaround for ARM Cortex-A510 erratum 2457168.
1060
1061	  The AMU counter AMEVCNTR01 (constant counter) should increment at the same rate
1062	  as the system counter. On affected Cortex-A510 cores AMEVCNTR01 increments
1063	  incorrectly giving a significantly higher output value.
1064
1065	  Work around this problem by returning 0 when reading the affected counter in
1066	  key locations that results in disabling all users of this counter. This effect
1067	  is the same to firmware disabling affected counters.
1068
1069	  If unsure, say Y.
1070
1071config ARM64_ERRATUM_2645198
1072	bool "Cortex-A715: 2645198: Workaround possible [ESR|FAR]_ELx corruption"
1073	default y
1074	help
1075	  This option adds the workaround for ARM Cortex-A715 erratum 2645198.
1076
1077	  If a Cortex-A715 cpu sees a page mapping permissions change from executable
1078	  to non-executable, it may corrupt the ESR_ELx and FAR_ELx registers on the
1079	  next instruction abort caused by permission fault.
1080
1081	  Only user-space does executable to non-executable permission transition via
1082	  mprotect() system call. Workaround the problem by doing a break-before-make
1083	  TLB invalidation, for all changes to executable user space mappings.
1084
1085	  If unsure, say Y.
1086
1087config ARM64_WORKAROUND_SPECULATIVE_UNPRIV_LOAD
1088	bool
1089
1090config ARM64_ERRATUM_2966298
1091	bool "Cortex-A520: 2966298: workaround for speculatively executed unprivileged load"
1092	select ARM64_WORKAROUND_SPECULATIVE_UNPRIV_LOAD
1093	default y
1094	help
1095	  This option adds the workaround for ARM Cortex-A520 erratum 2966298.
1096
1097	  On an affected Cortex-A520 core, a speculatively executed unprivileged
1098	  load might leak data from a privileged level via a cache side channel.
1099
1100	  Work around this problem by executing a TLBI before returning to EL0.
1101
1102	  If unsure, say Y.
1103
1104config ARM64_ERRATUM_3117295
1105	bool "Cortex-A510: 3117295: workaround for speculatively executed unprivileged load"
1106	select ARM64_WORKAROUND_SPECULATIVE_UNPRIV_LOAD
1107	default y
1108	help
1109	  This option adds the workaround for ARM Cortex-A510 erratum 3117295.
1110
1111	  On an affected Cortex-A510 core, a speculatively executed unprivileged
1112	  load might leak data from a privileged level via a cache side channel.
1113
1114	  Work around this problem by executing a TLBI before returning to EL0.
1115
1116	  If unsure, say Y.
1117
1118config ARM64_ERRATUM_3194386
1119	bool "Cortex-*/Neoverse-*: workaround for MSR SSBS not self-synchronizing"
1120	default y
1121	help
1122	  This option adds the workaround for the following errata:
1123
1124	  * ARM Cortex-A76 erratum 3324349
1125	  * ARM Cortex-A77 erratum 3324348
1126	  * ARM Cortex-A78 erratum 3324344
1127	  * ARM Cortex-A78C erratum 3324346
1128	  * ARM Cortex-A78C erratum 3324347
1129	  * ARM Cortex-A710 erratam 3324338
1130	  * ARM Cortex-A715 errartum 3456084
1131	  * ARM Cortex-A720 erratum 3456091
1132	  * ARM Cortex-A725 erratum 3456106
1133	  * ARM Cortex-X1 erratum 3324344
1134	  * ARM Cortex-X1C erratum 3324346
1135	  * ARM Cortex-X2 erratum 3324338
1136	  * ARM Cortex-X3 erratum 3324335
1137	  * ARM Cortex-X4 erratum 3194386
1138	  * ARM Cortex-X925 erratum 3324334
1139	  * ARM Neoverse-N1 erratum 3324349
1140	  * ARM Neoverse N2 erratum 3324339
1141	  * ARM Neoverse-N3 erratum 3456111
1142	  * ARM Neoverse-V1 erratum 3324341
1143	  * ARM Neoverse V2 erratum 3324336
1144	  * ARM Neoverse-V3 erratum 3312417
1145	  * ARM Neoverse-V3AE erratum 3312417
1146
1147	  On affected cores "MSR SSBS, #0" instructions may not affect
1148	  subsequent speculative instructions, which may permit unexepected
1149	  speculative store bypassing.
1150
1151	  Work around this problem by placing a Speculation Barrier (SB) or
1152	  Instruction Synchronization Barrier (ISB) after kernel changes to
1153	  SSBS. The presence of the SSBS special-purpose register is hidden
1154	  from hwcaps and EL0 reads of ID_AA64PFR1_EL1, such that userspace
1155	  will use the PR_SPEC_STORE_BYPASS prctl to change SSBS.
1156
1157	  If unsure, say Y.
1158
1159config CAVIUM_ERRATUM_22375
1160	bool "Cavium erratum 22375, 24313"
1161	default y
1162	help
1163	  Enable workaround for errata 22375 and 24313.
1164
1165	  This implements two gicv3-its errata workarounds for ThunderX. Both
1166	  with a small impact affecting only ITS table allocation.
1167
1168	    erratum 22375: only alloc 8MB table size
1169	    erratum 24313: ignore memory access type
1170
1171	  The fixes are in ITS initialization and basically ignore memory access
1172	  type and table size provided by the TYPER and BASER registers.
1173
1174	  If unsure, say Y.
1175
1176config CAVIUM_ERRATUM_23144
1177	bool "Cavium erratum 23144: ITS SYNC hang on dual socket system"
1178	depends on NUMA
1179	default y
1180	help
1181	  ITS SYNC command hang for cross node io and collections/cpu mapping.
1182
1183	  If unsure, say Y.
1184
1185config CAVIUM_ERRATUM_23154
1186	bool "Cavium errata 23154 and 38545: GICv3 lacks HW synchronisation"
1187	default y
1188	help
1189	  The ThunderX GICv3 implementation requires a modified version for
1190	  reading the IAR status to ensure data synchronization
1191	  (access to icc_iar1_el1 is not sync'ed before and after).
1192
1193	  It also suffers from erratum 38545 (also present on Marvell's
1194	  OcteonTX and OcteonTX2), resulting in deactivated interrupts being
1195	  spuriously presented to the CPU interface.
1196
1197	  If unsure, say Y.
1198
1199config CAVIUM_ERRATUM_27456
1200	bool "Cavium erratum 27456: Broadcast TLBI instructions may cause icache corruption"
1201	default y
1202	help
1203	  On ThunderX T88 pass 1.x through 2.1 parts, broadcast TLBI
1204	  instructions may cause the icache to become corrupted if it
1205	  contains data for a non-current ASID.  The fix is to
1206	  invalidate the icache when changing the mm context.
1207
1208	  If unsure, say Y.
1209
1210config CAVIUM_ERRATUM_30115
1211	bool "Cavium erratum 30115: Guest may disable interrupts in host"
1212	default y
1213	help
1214	  On ThunderX T88 pass 1.x through 2.2, T81 pass 1.0 through
1215	  1.2, and T83 Pass 1.0, KVM guest execution may disable
1216	  interrupts in host. Trapping both GICv3 group-0 and group-1
1217	  accesses sidesteps the issue.
1218
1219	  If unsure, say Y.
1220
1221config CAVIUM_TX2_ERRATUM_219
1222	bool "Cavium ThunderX2 erratum 219: PRFM between TTBR change and ISB fails"
1223	default y
1224	help
1225	  On Cavium ThunderX2, a load, store or prefetch instruction between a
1226	  TTBR update and the corresponding context synchronizing operation can
1227	  cause a spurious Data Abort to be delivered to any hardware thread in
1228	  the CPU core.
1229
1230	  Work around the issue by avoiding the problematic code sequence and
1231	  trapping KVM guest TTBRx_EL1 writes to EL2 when SMT is enabled. The
1232	  trap handler performs the corresponding register access, skips the
1233	  instruction and ensures context synchronization by virtue of the
1234	  exception return.
1235
1236	  If unsure, say Y.
1237
1238config FUJITSU_ERRATUM_010001
1239	bool "Fujitsu-A64FX erratum E#010001: Undefined fault may occur wrongly"
1240	default y
1241	help
1242	  This option adds a workaround for Fujitsu-A64FX erratum E#010001.
1243	  On some variants of the Fujitsu-A64FX cores ver(1.0, 1.1), memory
1244	  accesses may cause undefined fault (Data abort, DFSC=0b111111).
1245	  This fault occurs under a specific hardware condition when a
1246	  load/store instruction performs an address translation using:
1247	  case-1  TTBR0_EL1 with TCR_EL1.NFD0 == 1.
1248	  case-2  TTBR0_EL2 with TCR_EL2.NFD0 == 1.
1249	  case-3  TTBR1_EL1 with TCR_EL1.NFD1 == 1.
1250	  case-4  TTBR1_EL2 with TCR_EL2.NFD1 == 1.
1251
1252	  The workaround is to ensure these bits are clear in TCR_ELx.
1253	  The workaround only affects the Fujitsu-A64FX.
1254
1255	  If unsure, say Y.
1256
1257config HISILICON_ERRATUM_161600802
1258	bool "Hip07 161600802: Erroneous redistributor VLPI base"
1259	default y
1260	help
1261	  The HiSilicon Hip07 SoC uses the wrong redistributor base
1262	  when issued ITS commands such as VMOVP and VMAPP, and requires
1263	  a 128kB offset to be applied to the target address in this commands.
1264
1265	  If unsure, say Y.
1266
1267config HISILICON_ERRATUM_162100801
1268	bool "Hip09 162100801 erratum support"
1269	default y
1270	help
1271	  When enabling GICv4.1 in hip09, VMAPP will fail to clear some caches
1272	  during unmapping operation, which will cause some vSGIs lost.
1273	  To fix the issue, invalidate related vPE cache through GICR_INVALLR
1274	  after VMOVP.
1275
1276	  If unsure, say Y.
1277
1278config QCOM_FALKOR_ERRATUM_1003
1279	bool "Falkor E1003: Incorrect translation due to ASID change"
1280	default y
1281	help
1282	  On Falkor v1, an incorrect ASID may be cached in the TLB when ASID
1283	  and BADDR are changed together in TTBRx_EL1. Since we keep the ASID
1284	  in TTBR1_EL1, this situation only occurs in the entry trampoline and
1285	  then only for entries in the walk cache, since the leaf translation
1286	  is unchanged. Work around the erratum by invalidating the walk cache
1287	  entries for the trampoline before entering the kernel proper.
1288
1289config QCOM_FALKOR_ERRATUM_1009
1290	bool "Falkor E1009: Prematurely complete a DSB after a TLBI"
1291	default y
1292	select ARM64_WORKAROUND_REPEAT_TLBI
1293	help
1294	  On Falkor v1, the CPU may prematurely complete a DSB following a
1295	  TLBI xxIS invalidate maintenance operation. Repeat the TLBI operation
1296	  one more time to fix the issue.
1297
1298	  If unsure, say Y.
1299
1300config QCOM_QDF2400_ERRATUM_0065
1301	bool "QDF2400 E0065: Incorrect GITS_TYPER.ITT_Entry_size"
1302	default y
1303	help
1304	  On Qualcomm Datacenter Technologies QDF2400 SoC, ITS hardware reports
1305	  ITE size incorrectly. The GITS_TYPER.ITT_Entry_size field should have
1306	  been indicated as 16Bytes (0xf), not 8Bytes (0x7).
1307
1308	  If unsure, say Y.
1309
1310config QCOM_FALKOR_ERRATUM_E1041
1311	bool "Falkor E1041: Speculative instruction fetches might cause errant memory access"
1312	default y
1313	help
1314	  Falkor CPU may speculatively fetch instructions from an improper
1315	  memory location when MMU translation is changed from SCTLR_ELn[M]=1
1316	  to SCTLR_ELn[M]=0. Prefix an ISB instruction to fix the problem.
1317
1318	  If unsure, say Y.
1319
1320config NVIDIA_CARMEL_CNP_ERRATUM
1321	bool "NVIDIA Carmel CNP: CNP on Carmel semantically different than ARM cores"
1322	default y
1323	help
1324	  If CNP is enabled on Carmel cores, non-sharable TLBIs on a core will not
1325	  invalidate shared TLB entries installed by a different core, as it would
1326	  on standard ARM cores.
1327
1328	  If unsure, say Y.
1329
1330config ROCKCHIP_ERRATUM_3568002
1331	bool "Rockchip 3568002: GIC600 can not access physical addresses higher than 4GB"
1332	default y
1333	help
1334	  The Rockchip RK3566 and RK3568 GIC600 SoC integrations have AXI
1335	  addressing limited to the first 32bit of physical address space.
1336
1337	  If unsure, say Y.
1338
1339config ROCKCHIP_ERRATUM_3588001
1340	bool "Rockchip 3588001: GIC600 can not support shareability attributes"
1341	default y
1342	help
1343	  The Rockchip RK3588 GIC600 SoC integration does not support ACE/ACE-lite.
1344	  This means, that its sharability feature may not be used, even though it
1345	  is supported by the IP itself.
1346
1347	  If unsure, say Y.
1348
1349config SOCIONEXT_SYNQUACER_PREITS
1350	bool "Socionext Synquacer: Workaround for GICv3 pre-ITS"
1351	default y
1352	help
1353	  Socionext Synquacer SoCs implement a separate h/w block to generate
1354	  MSI doorbell writes with non-zero values for the device ID.
1355
1356	  If unsure, say Y.
1357
1358endmenu # "ARM errata workarounds via the alternatives framework"
1359
1360choice
1361	prompt "Page size"
1362	default ARM64_4K_PAGES
1363	help
1364	  Page size (translation granule) configuration.
1365
1366config ARM64_4K_PAGES
1367	bool "4KB"
1368	select HAVE_PAGE_SIZE_4KB
1369	help
1370	  This feature enables 4KB pages support.
1371
1372config ARM64_16K_PAGES
1373	bool "16KB"
1374	select HAVE_PAGE_SIZE_16KB
1375	help
1376	  The system will use 16KB pages support. AArch32 emulation
1377	  requires applications compiled with 16K (or a multiple of 16K)
1378	  aligned segments.
1379
1380config ARM64_64K_PAGES
1381	bool "64KB"
1382	select HAVE_PAGE_SIZE_64KB
1383	help
1384	  This feature enables 64KB pages support (4KB by default)
1385	  allowing only two levels of page tables and faster TLB
1386	  look-up. AArch32 emulation requires applications compiled
1387	  with 64K aligned segments.
1388
1389endchoice
1390
1391choice
1392	prompt "Virtual address space size"
1393	default ARM64_VA_BITS_52
1394	help
1395	  Allows choosing one of multiple possible virtual address
1396	  space sizes. The level of translation table is determined by
1397	  a combination of page size and virtual address space size.
1398
1399config ARM64_VA_BITS_36
1400	bool "36-bit" if EXPERT
1401	depends on PAGE_SIZE_16KB
1402
1403config ARM64_VA_BITS_39
1404	bool "39-bit"
1405	depends on PAGE_SIZE_4KB
1406
1407config ARM64_VA_BITS_42
1408	bool "42-bit"
1409	depends on PAGE_SIZE_64KB
1410
1411config ARM64_VA_BITS_47
1412	bool "47-bit"
1413	depends on PAGE_SIZE_16KB
1414
1415config ARM64_VA_BITS_48
1416	bool "48-bit"
1417
1418config ARM64_VA_BITS_52
1419	bool "52-bit"
1420	help
1421	  Enable 52-bit virtual addressing for userspace when explicitly
1422	  requested via a hint to mmap(). The kernel will also use 52-bit
1423	  virtual addresses for its own mappings (provided HW support for
1424	  this feature is available, otherwise it reverts to 48-bit).
1425
1426	  NOTE: Enabling 52-bit virtual addressing in conjunction with
1427	  ARMv8.3 Pointer Authentication will result in the PAC being
1428	  reduced from 7 bits to 3 bits, which may have a significant
1429	  impact on its susceptibility to brute-force attacks.
1430
1431	  If unsure, select 48-bit virtual addressing instead.
1432
1433endchoice
1434
1435config ARM64_FORCE_52BIT
1436	bool "Force 52-bit virtual addresses for userspace"
1437	depends on ARM64_VA_BITS_52 && EXPERT
1438	help
1439	  For systems with 52-bit userspace VAs enabled, the kernel will attempt
1440	  to maintain compatibility with older software by providing 48-bit VAs
1441	  unless a hint is supplied to mmap.
1442
1443	  This configuration option disables the 48-bit compatibility logic, and
1444	  forces all userspace addresses to be 52-bit on HW that supports it. One
1445	  should only enable this configuration option for stress testing userspace
1446	  memory management code. If unsure say N here.
1447
1448config ARM64_VA_BITS
1449	int
1450	default 36 if ARM64_VA_BITS_36
1451	default 39 if ARM64_VA_BITS_39
1452	default 42 if ARM64_VA_BITS_42
1453	default 47 if ARM64_VA_BITS_47
1454	default 48 if ARM64_VA_BITS_48
1455	default 52 if ARM64_VA_BITS_52
1456
1457choice
1458	prompt "Physical address space size"
1459	default ARM64_PA_BITS_48
1460	help
1461	  Choose the maximum physical address range that the kernel will
1462	  support.
1463
1464config ARM64_PA_BITS_48
1465	bool "48-bit"
1466	depends on ARM64_64K_PAGES || !ARM64_VA_BITS_52
1467
1468config ARM64_PA_BITS_52
1469	bool "52-bit"
1470	depends on ARM64_64K_PAGES || ARM64_VA_BITS_52
1471	help
1472	  Enable support for a 52-bit physical address space, introduced as
1473	  part of the ARMv8.2-LPA extension.
1474
1475	  With this enabled, the kernel will also continue to work on CPUs that
1476	  do not support ARMv8.2-LPA, but with some added memory overhead (and
1477	  minor performance overhead).
1478
1479endchoice
1480
1481config ARM64_PA_BITS
1482	int
1483	default 48 if ARM64_PA_BITS_48
1484	default 52 if ARM64_PA_BITS_52
1485
1486config ARM64_LPA2
1487	def_bool y
1488	depends on ARM64_PA_BITS_52 && !ARM64_64K_PAGES
1489
1490choice
1491	prompt "Endianness"
1492	default CPU_LITTLE_ENDIAN
1493	help
1494	  Select the endianness of data accesses performed by the CPU. Userspace
1495	  applications will need to be compiled and linked for the endianness
1496	  that is selected here.
1497
1498config CPU_BIG_ENDIAN
1499	bool "Build big-endian kernel"
1500	# https://github.com/llvm/llvm-project/commit/1379b150991f70a5782e9a143c2ba5308da1161c
1501	depends on (AS_IS_GNU || AS_VERSION >= 150000) && BROKEN
1502	help
1503	  Say Y if you plan on running a kernel with a big-endian userspace.
1504
1505config CPU_LITTLE_ENDIAN
1506	bool "Build little-endian kernel"
1507	help
1508	  Say Y if you plan on running a kernel with a little-endian userspace.
1509	  This is usually the case for distributions targeting arm64.
1510
1511endchoice
1512
1513config NR_CPUS
1514	int "Maximum number of CPUs (2-4096)"
1515	range 2 4096
1516	default "512"
1517
1518config HOTPLUG_CPU
1519	bool "Support for hot-pluggable CPUs"
1520	select GENERIC_IRQ_MIGRATION
1521	help
1522	  Say Y here to experiment with turning CPUs off and on.  CPUs
1523	  can be controlled through /sys/devices/system/cpu.
1524
1525# Common NUMA Features
1526config NUMA
1527	bool "NUMA Memory Allocation and Scheduler Support"
1528	select GENERIC_ARCH_NUMA
1529	select OF_NUMA
1530	select HAVE_SETUP_PER_CPU_AREA
1531	select NEED_PER_CPU_EMBED_FIRST_CHUNK
1532	select NEED_PER_CPU_PAGE_FIRST_CHUNK
1533	select USE_PERCPU_NUMA_NODE_ID
1534	help
1535	  Enable NUMA (Non-Uniform Memory Access) support.
1536
1537	  The kernel will try to allocate memory used by a CPU on the
1538	  local memory of the CPU and add some more
1539	  NUMA awareness to the kernel.
1540
1541config NODES_SHIFT
1542	int "Maximum NUMA Nodes (as a power of 2)"
1543	range 1 10
1544	default "4"
1545	depends on NUMA
1546	help
1547	  Specify the maximum number of NUMA Nodes available on the target
1548	  system.  Increases memory reserved to accommodate various tables.
1549
1550source "kernel/Kconfig.hz"
1551
1552config ARCH_SPARSEMEM_ENABLE
1553	def_bool y
1554	select SPARSEMEM_VMEMMAP_ENABLE
1555	select SPARSEMEM_VMEMMAP
1556
1557config HW_PERF_EVENTS
1558	def_bool y
1559	depends on ARM_PMU
1560
1561# Supported by clang >= 7.0 or GCC >= 12.0.0
1562config CC_HAVE_SHADOW_CALL_STACK
1563	def_bool $(cc-option, -fsanitize=shadow-call-stack -ffixed-x18)
1564
1565config PARAVIRT
1566	bool "Enable paravirtualization code"
1567	help
1568	  This changes the kernel so it can modify itself when it is run
1569	  under a hypervisor, potentially improving performance significantly
1570	  over full virtualization.
1571
1572config PARAVIRT_TIME_ACCOUNTING
1573	bool "Paravirtual steal time accounting"
1574	select PARAVIRT
1575	help
1576	  Select this option to enable fine granularity task steal time
1577	  accounting. Time spent executing other tasks in parallel with
1578	  the current vCPU is discounted from the vCPU power. To account for
1579	  that, there can be a small performance impact.
1580
1581	  If in doubt, say N here.
1582
1583config ARCH_SUPPORTS_KEXEC
1584	def_bool PM_SLEEP_SMP
1585
1586config ARCH_SUPPORTS_KEXEC_FILE
1587	def_bool y
1588
1589config ARCH_SELECTS_KEXEC_FILE
1590	def_bool y
1591	depends on KEXEC_FILE
1592	select HAVE_IMA_KEXEC if IMA
1593
1594config ARCH_SUPPORTS_KEXEC_SIG
1595	def_bool y
1596
1597config ARCH_SUPPORTS_KEXEC_IMAGE_VERIFY_SIG
1598	def_bool y
1599
1600config ARCH_DEFAULT_KEXEC_IMAGE_VERIFY_SIG
1601	def_bool y
1602
1603config ARCH_SUPPORTS_KEXEC_HANDOVER
1604	def_bool y
1605
1606config ARCH_SUPPORTS_CRASH_DUMP
1607	def_bool y
1608
1609config ARCH_DEFAULT_CRASH_DUMP
1610	def_bool y
1611
1612config ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION
1613	def_bool CRASH_RESERVE
1614
1615config TRANS_TABLE
1616	def_bool y
1617	depends on HIBERNATION || KEXEC_CORE
1618
1619config XEN_DOM0
1620	def_bool y
1621	depends on XEN
1622
1623config XEN
1624	bool "Xen guest support on ARM64"
1625	depends on ARM64 && OF
1626	select SWIOTLB_XEN
1627	select PARAVIRT
1628	help
1629	  Say Y if you want to run Linux in a Virtual Machine on Xen on ARM64.
1630
1631# include/linux/mmzone.h requires the following to be true:
1632#
1633#   MAX_PAGE_ORDER + PAGE_SHIFT <= SECTION_SIZE_BITS
1634#
1635# so the maximum value of MAX_PAGE_ORDER is SECTION_SIZE_BITS - PAGE_SHIFT:
1636#
1637#     | SECTION_SIZE_BITS |  PAGE_SHIFT  |  max MAX_PAGE_ORDER  |  default MAX_PAGE_ORDER |
1638# ----+-------------------+--------------+----------------------+-------------------------+
1639# 4K  |       27          |      12      |       15             |         10              |
1640# 16K |       27          |      14      |       13             |         11              |
1641# 64K |       29          |      16      |       13             |         13              |
1642config ARCH_FORCE_MAX_ORDER
1643	int
1644	default "13" if ARM64_64K_PAGES
1645	default "11" if ARM64_16K_PAGES
1646	default "10"
1647	help
1648	  The kernel page allocator limits the size of maximal physically
1649	  contiguous allocations. The limit is called MAX_PAGE_ORDER and it
1650	  defines the maximal power of two of number of pages that can be
1651	  allocated as a single contiguous block. This option allows
1652	  overriding the default setting when ability to allocate very
1653	  large blocks of physically contiguous memory is required.
1654
1655	  The maximal size of allocation cannot exceed the size of the
1656	  section, so the value of MAX_PAGE_ORDER should satisfy
1657
1658	    MAX_PAGE_ORDER + PAGE_SHIFT <= SECTION_SIZE_BITS
1659
1660	  Don't change if unsure.
1661
1662config UNMAP_KERNEL_AT_EL0
1663	bool "Unmap kernel when running in userspace (KPTI)" if EXPERT
1664	default y
1665	help
1666	  Speculation attacks against some high-performance processors can
1667	  be used to bypass MMU permission checks and leak kernel data to
1668	  userspace. This can be defended against by unmapping the kernel
1669	  when running in userspace, mapping it back in on exception entry
1670	  via a trampoline page in the vector table.
1671
1672	  If unsure, say Y.
1673
1674config MITIGATE_SPECTRE_BRANCH_HISTORY
1675	bool "Mitigate Spectre style attacks against branch history" if EXPERT
1676	default y
1677	help
1678	  Speculation attacks against some high-performance processors can
1679	  make use of branch history to influence future speculation.
1680	  When taking an exception from user-space, a sequence of branches
1681	  or a firmware call overwrites the branch history.
1682
1683config ARM64_SW_TTBR0_PAN
1684	bool "Emulate Privileged Access Never using TTBR0_EL1 switching"
1685	depends on !KCSAN
1686	select ARM64_PAN
1687	help
1688	  Enabling this option prevents the kernel from accessing
1689	  user-space memory directly by pointing TTBR0_EL1 to a reserved
1690	  zeroed area and reserved ASID. The user access routines
1691	  restore the valid TTBR0_EL1 temporarily.
1692
1693config ARM64_TAGGED_ADDR_ABI
1694	bool "Enable the tagged user addresses syscall ABI"
1695	default y
1696	help
1697	  When this option is enabled, user applications can opt in to a
1698	  relaxed ABI via prctl() allowing tagged addresses to be passed
1699	  to system calls as pointer arguments. For details, see
1700	  Documentation/arch/arm64/tagged-address-abi.rst.
1701
1702menuconfig COMPAT
1703	bool "Kernel support for 32-bit EL0"
1704	depends on ARM64_4K_PAGES || EXPERT
1705	select HAVE_UID16
1706	select OLD_SIGSUSPEND3
1707	select COMPAT_OLD_SIGACTION
1708	help
1709	  This option enables support for a 32-bit EL0 running under a 64-bit
1710	  kernel at EL1. AArch32-specific components such as system calls,
1711	  the user helper functions, VFP support and the ptrace interface are
1712	  handled appropriately by the kernel.
1713
1714	  If you use a page size other than 4KB (i.e, 16KB or 64KB), please be aware
1715	  that you will only be able to execute AArch32 binaries that were compiled
1716	  with page size aligned segments.
1717
1718	  If you want to execute 32-bit userspace applications, say Y.
1719
1720if COMPAT
1721
1722config KUSER_HELPERS
1723	bool "Enable kuser helpers page for 32-bit applications"
1724	default y
1725	help
1726	  Warning: disabling this option may break 32-bit user programs.
1727
1728	  Provide kuser helpers to compat tasks. The kernel provides
1729	  helper code to userspace in read only form at a fixed location
1730	  to allow userspace to be independent of the CPU type fitted to
1731	  the system. This permits binaries to be run on ARMv4 through
1732	  to ARMv8 without modification.
1733
1734	  See Documentation/arch/arm/kernel_user_helpers.rst for details.
1735
1736	  However, the fixed address nature of these helpers can be used
1737	  by ROP (return orientated programming) authors when creating
1738	  exploits.
1739
1740	  If all of the binaries and libraries which run on your platform
1741	  are built specifically for your platform, and make no use of
1742	  these helpers, then you can turn this option off to hinder
1743	  such exploits. However, in that case, if a binary or library
1744	  relying on those helpers is run, it will not function correctly.
1745
1746	  Say N here only if you are absolutely certain that you do not
1747	  need these helpers; otherwise, the safe option is to say Y.
1748
1749config COMPAT_VDSO
1750	bool "Enable vDSO for 32-bit applications"
1751	depends on !CPU_BIG_ENDIAN
1752	depends on (CC_IS_CLANG && LD_IS_LLD) || "$(CROSS_COMPILE_COMPAT)" != ""
1753	select GENERIC_COMPAT_VDSO
1754	default y
1755	help
1756	  Place in the process address space of 32-bit applications an
1757	  ELF shared object providing fast implementations of gettimeofday
1758	  and clock_gettime.
1759
1760	  You must have a 32-bit build of glibc 2.22 or later for programs
1761	  to seamlessly take advantage of this.
1762
1763config THUMB2_COMPAT_VDSO
1764	bool "Compile the 32-bit vDSO for Thumb-2 mode" if EXPERT
1765	depends on COMPAT_VDSO
1766	default y
1767	help
1768	  Compile the compat vDSO with '-mthumb -fomit-frame-pointer' if y,
1769	  otherwise with '-marm'.
1770
1771config COMPAT_ALIGNMENT_FIXUPS
1772	bool "Fix up misaligned multi-word loads and stores in user space"
1773
1774menuconfig ARMV8_DEPRECATED
1775	bool "Emulate deprecated/obsolete ARMv8 instructions"
1776	depends on SYSCTL
1777	help
1778	  Legacy software support may require certain instructions
1779	  that have been deprecated or obsoleted in the architecture.
1780
1781	  Enable this config to enable selective emulation of these
1782	  features.
1783
1784	  If unsure, say Y
1785
1786if ARMV8_DEPRECATED
1787
1788config SWP_EMULATION
1789	bool "Emulate SWP/SWPB instructions"
1790	help
1791	  ARMv8 obsoletes the use of A32 SWP/SWPB instructions such that
1792	  they are always undefined. Say Y here to enable software
1793	  emulation of these instructions for userspace using LDXR/STXR.
1794	  This feature can be controlled at runtime with the abi.swp
1795	  sysctl which is disabled by default.
1796
1797	  In some older versions of glibc [<=2.8] SWP is used during futex
1798	  trylock() operations with the assumption that the code will not
1799	  be preempted. This invalid assumption may be more likely to fail
1800	  with SWP emulation enabled, leading to deadlock of the user
1801	  application.
1802
1803	  NOTE: when accessing uncached shared regions, LDXR/STXR rely
1804	  on an external transaction monitoring block called a global
1805	  monitor to maintain update atomicity. If your system does not
1806	  implement a global monitor, this option can cause programs that
1807	  perform SWP operations to uncached memory to deadlock.
1808
1809	  If unsure, say Y
1810
1811config CP15_BARRIER_EMULATION
1812	bool "Emulate CP15 Barrier instructions"
1813	help
1814	  The CP15 barrier instructions - CP15ISB, CP15DSB, and
1815	  CP15DMB - are deprecated in ARMv8 (and ARMv7). It is
1816	  strongly recommended to use the ISB, DSB, and DMB
1817	  instructions instead.
1818
1819	  Say Y here to enable software emulation of these
1820	  instructions for AArch32 userspace code. When this option is
1821	  enabled, CP15 barrier usage is traced which can help
1822	  identify software that needs updating. This feature can be
1823	  controlled at runtime with the abi.cp15_barrier sysctl.
1824
1825	  If unsure, say Y
1826
1827config SETEND_EMULATION
1828	bool "Emulate SETEND instruction"
1829	help
1830	  The SETEND instruction alters the data-endianness of the
1831	  AArch32 EL0, and is deprecated in ARMv8.
1832
1833	  Say Y here to enable software emulation of the instruction
1834	  for AArch32 userspace code. This feature can be controlled
1835	  at runtime with the abi.setend sysctl.
1836
1837	  Note: All the cpus on the system must have mixed endian support at EL0
1838	  for this feature to be enabled. If a new CPU - which doesn't support mixed
1839	  endian - is hotplugged in after this feature has been enabled, there could
1840	  be unexpected results in the applications.
1841
1842	  If unsure, say Y
1843endif # ARMV8_DEPRECATED
1844
1845endif # COMPAT
1846
1847menu "ARMv8.1 architectural features"
1848
1849config ARM64_HW_AFDBM
1850	bool "Support for hardware updates of the Access and Dirty page flags"
1851	default y
1852	help
1853	  The ARMv8.1 architecture extensions introduce support for
1854	  hardware updates of the access and dirty information in page
1855	  table entries. When enabled in TCR_EL1 (HA and HD bits) on
1856	  capable processors, accesses to pages with PTE_AF cleared will
1857	  set this bit instead of raising an access flag fault.
1858	  Similarly, writes to read-only pages with the DBM bit set will
1859	  clear the read-only bit (AP[2]) instead of raising a
1860	  permission fault.
1861
1862	  Kernels built with this configuration option enabled continue
1863	  to work on pre-ARMv8.1 hardware and the performance impact is
1864	  minimal. If unsure, say Y.
1865
1866config ARM64_PAN
1867	bool "Enable support for Privileged Access Never (PAN)"
1868	default y
1869	help
1870	  Privileged Access Never (PAN; part of the ARMv8.1 Extensions)
1871	  prevents the kernel or hypervisor from accessing user-space (EL0)
1872	  memory directly.
1873
1874	  Choosing this option will cause any unprotected (not using
1875	  copy_to_user et al) memory access to fail with a permission fault.
1876
1877	  The feature is detected at runtime, and will remain as a 'nop'
1878	  instruction if the cpu does not implement the feature.
1879
1880config ARM64_LSE_ATOMICS
1881	bool
1882	default ARM64_USE_LSE_ATOMICS
1883
1884config ARM64_USE_LSE_ATOMICS
1885	bool "Atomic instructions"
1886	default y
1887	help
1888	  As part of the Large System Extensions, ARMv8.1 introduces new
1889	  atomic instructions that are designed specifically to scale in
1890	  very large systems.
1891
1892	  Say Y here to make use of these instructions for the in-kernel
1893	  atomic routines. This incurs a small overhead on CPUs that do
1894	  not support these instructions.
1895
1896endmenu # "ARMv8.1 architectural features"
1897
1898menu "ARMv8.2 architectural features"
1899
1900config ARM64_PMEM
1901	bool "Enable support for persistent memory"
1902	select ARCH_HAS_PMEM_API
1903	select ARCH_HAS_UACCESS_FLUSHCACHE
1904	help
1905	  Say Y to enable support for the persistent memory API based on the
1906	  ARMv8.2 DCPoP feature.
1907
1908	  The feature is detected at runtime, and the kernel will use DC CVAC
1909	  operations if DC CVAP is not supported (following the behaviour of
1910	  DC CVAP itself if the system does not define a point of persistence).
1911
1912config ARM64_RAS_EXTN
1913	bool "Enable support for RAS CPU Extensions"
1914	default y
1915	help
1916	  CPUs that support the Reliability, Availability and Serviceability
1917	  (RAS) Extensions, part of ARMv8.2 are able to track faults and
1918	  errors, classify them and report them to software.
1919
1920	  On CPUs with these extensions system software can use additional
1921	  barriers to determine if faults are pending and read the
1922	  classification from a new set of registers.
1923
1924	  Selecting this feature will allow the kernel to use these barriers
1925	  and access the new registers if the system supports the extension.
1926	  Platform RAS features may additionally depend on firmware support.
1927
1928config ARM64_CNP
1929	bool "Enable support for Common Not Private (CNP) translations"
1930	default y
1931	help
1932	  Common Not Private (CNP) allows translation table entries to
1933	  be shared between different PEs in the same inner shareable
1934	  domain, so the hardware can use this fact to optimise the
1935	  caching of such entries in the TLB.
1936
1937	  Selecting this option allows the CNP feature to be detected
1938	  at runtime, and does not affect PEs that do not implement
1939	  this feature.
1940
1941endmenu # "ARMv8.2 architectural features"
1942
1943menu "ARMv8.3 architectural features"
1944
1945config ARM64_PTR_AUTH
1946	bool "Enable support for pointer authentication"
1947	default y
1948	help
1949	  Pointer authentication (part of the ARMv8.3 Extensions) provides
1950	  instructions for signing and authenticating pointers against secret
1951	  keys, which can be used to mitigate Return Oriented Programming (ROP)
1952	  and other attacks.
1953
1954	  This option enables these instructions at EL0 (i.e. for userspace).
1955	  Choosing this option will cause the kernel to initialise secret keys
1956	  for each process at exec() time, with these keys being
1957	  context-switched along with the process.
1958
1959	  The feature is detected at runtime. If the feature is not present in
1960	  hardware it will not be advertised to userspace/KVM guest nor will it
1961	  be enabled.
1962
1963	  If the feature is present on the boot CPU but not on a late CPU, then
1964	  the late CPU will be parked. Also, if the boot CPU does not have
1965	  address auth and the late CPU has then the late CPU will still boot
1966	  but with the feature disabled. On such a system, this option should
1967	  not be selected.
1968
1969config ARM64_PTR_AUTH_KERNEL
1970	bool "Use pointer authentication for kernel"
1971	default y
1972	depends on ARM64_PTR_AUTH
1973	# Modern compilers insert a .note.gnu.property section note for PAC
1974	# which is only understood by binutils starting with version 2.33.1.
1975	depends on LD_IS_LLD || LD_VERSION >= 23301 || (CC_IS_GCC && GCC_VERSION < 90100)
1976	depends on !CC_IS_CLANG || AS_HAS_CFI_NEGATE_RA_STATE
1977	depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_ARGS)
1978	help
1979	  If the compiler supports the -mbranch-protection or
1980	  -msign-return-address flag (e.g. GCC 7 or later), then this option
1981	  will cause the kernel itself to be compiled with return address
1982	  protection. In this case, and if the target hardware is known to
1983	  support pointer authentication, then CONFIG_STACKPROTECTOR can be
1984	  disabled with minimal loss of protection.
1985
1986	  This feature works with FUNCTION_GRAPH_TRACER option only if
1987	  DYNAMIC_FTRACE_WITH_ARGS is enabled.
1988
1989config CC_HAS_BRANCH_PROT_PAC_RET
1990	# GCC 9 or later, clang 8 or later
1991	def_bool $(cc-option,-mbranch-protection=pac-ret+leaf)
1992
1993config AS_HAS_CFI_NEGATE_RA_STATE
1994	# binutils 2.34+
1995	def_bool $(as-instr,.cfi_startproc\n.cfi_negate_ra_state\n.cfi_endproc\n)
1996
1997endmenu # "ARMv8.3 architectural features"
1998
1999menu "ARMv8.4 architectural features"
2000
2001config ARM64_AMU_EXTN
2002	bool "Enable support for the Activity Monitors Unit CPU extension"
2003	default y
2004	help
2005	  The activity monitors extension is an optional extension introduced
2006	  by the ARMv8.4 CPU architecture. This enables support for version 1
2007	  of the activity monitors architecture, AMUv1.
2008
2009	  To enable the use of this extension on CPUs that implement it, say Y.
2010
2011	  Note that for architectural reasons, firmware _must_ implement AMU
2012	  support when running on CPUs that present the activity monitors
2013	  extension. The required support is present in:
2014	    * Version 1.5 and later of the ARM Trusted Firmware
2015
2016	  For kernels that have this configuration enabled but boot with broken
2017	  firmware, you may need to say N here until the firmware is fixed.
2018	  Otherwise you may experience firmware panics or lockups when
2019	  accessing the counter registers. Even if you are not observing these
2020	  symptoms, the values returned by the register reads might not
2021	  correctly reflect reality. Most commonly, the value read will be 0,
2022	  indicating that the counter is not enabled.
2023
2024config ARM64_TLB_RANGE
2025	bool "Enable support for tlbi range feature"
2026	default y
2027	help
2028	  ARMv8.4-TLBI provides TLBI invalidation instruction that apply to a
2029	  range of input addresses.
2030
2031endmenu # "ARMv8.4 architectural features"
2032
2033menu "ARMv8.5 architectural features"
2034
2035config AS_HAS_ARMV8_5
2036	def_bool $(cc-option,-Wa$(comma)-march=armv8.5-a)
2037
2038config ARM64_BTI
2039	bool "Branch Target Identification support"
2040	default y
2041	help
2042	  Branch Target Identification (part of the ARMv8.5 Extensions)
2043	  provides a mechanism to limit the set of locations to which computed
2044	  branch instructions such as BR or BLR can jump.
2045
2046	  To make use of BTI on CPUs that support it, say Y.
2047
2048	  BTI is intended to provide complementary protection to other control
2049	  flow integrity protection mechanisms, such as the Pointer
2050	  authentication mechanism provided as part of the ARMv8.3 Extensions.
2051	  For this reason, it does not make sense to enable this option without
2052	  also enabling support for pointer authentication.  Thus, when
2053	  enabling this option you should also select ARM64_PTR_AUTH=y.
2054
2055	  Userspace binaries must also be specifically compiled to make use of
2056	  this mechanism.  If you say N here or the hardware does not support
2057	  BTI, such binaries can still run, but you get no additional
2058	  enforcement of branch destinations.
2059
2060config ARM64_BTI_KERNEL
2061	bool "Use Branch Target Identification for kernel"
2062	default y
2063	depends on ARM64_BTI
2064	depends on ARM64_PTR_AUTH_KERNEL
2065	depends on CC_HAS_BRANCH_PROT_PAC_RET_BTI
2066	# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94697
2067	depends on !CC_IS_GCC || GCC_VERSION >= 100100
2068	# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106671
2069	depends on !CC_IS_GCC
2070	depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_ARGS)
2071	help
2072	  Build the kernel with Branch Target Identification annotations
2073	  and enable enforcement of this for kernel code. When this option
2074	  is enabled and the system supports BTI all kernel code including
2075	  modular code must have BTI enabled.
2076
2077config CC_HAS_BRANCH_PROT_PAC_RET_BTI
2078	# GCC 9 or later, clang 8 or later
2079	def_bool $(cc-option,-mbranch-protection=pac-ret+leaf+bti)
2080
2081config ARM64_E0PD
2082	bool "Enable support for E0PD"
2083	default y
2084	help
2085	  E0PD (part of the ARMv8.5 extensions) allows us to ensure
2086	  that EL0 accesses made via TTBR1 always fault in constant time,
2087	  providing similar benefits to KASLR as those provided by KPTI, but
2088	  with lower overhead and without disrupting legitimate access to
2089	  kernel memory such as SPE.
2090
2091	  This option enables E0PD for TTBR1 where available.
2092
2093config ARM64_AS_HAS_MTE
2094	# Initial support for MTE went in binutils 2.32.0, checked with
2095	# ".arch armv8.5-a+memtag" below. However, this was incomplete
2096	# as a late addition to the final architecture spec (LDGM/STGM)
2097	# is only supported in the newer 2.32.x and 2.33 binutils
2098	# versions, hence the extra "stgm" instruction check below.
2099	def_bool $(as-instr,.arch armv8.5-a+memtag\nstgm xzr$(comma)[x0])
2100
2101config ARM64_MTE
2102	bool "Memory Tagging Extension support"
2103	default y
2104	depends on ARM64_AS_HAS_MTE && ARM64_TAGGED_ADDR_ABI
2105	depends on AS_HAS_ARMV8_5
2106	# Required for tag checking in the uaccess routines
2107	select ARM64_PAN
2108	select ARCH_HAS_SUBPAGE_FAULTS
2109	select ARCH_USES_HIGH_VMA_FLAGS
2110	select ARCH_USES_PG_ARCH_2
2111	select ARCH_USES_PG_ARCH_3
2112	help
2113	  Memory Tagging (part of the ARMv8.5 Extensions) provides
2114	  architectural support for run-time, always-on detection of
2115	  various classes of memory error to aid with software debugging
2116	  to eliminate vulnerabilities arising from memory-unsafe
2117	  languages.
2118
2119	  This option enables the support for the Memory Tagging
2120	  Extension at EL0 (i.e. for userspace).
2121
2122	  Selecting this option allows the feature to be detected at
2123	  runtime. Any secondary CPU not implementing this feature will
2124	  not be allowed a late bring-up.
2125
2126	  Userspace binaries that want to use this feature must
2127	  explicitly opt in. The mechanism for the userspace is
2128	  described in:
2129
2130	  Documentation/arch/arm64/memory-tagging-extension.rst.
2131
2132endmenu # "ARMv8.5 architectural features"
2133
2134menu "ARMv8.7 architectural features"
2135
2136config ARM64_EPAN
2137	bool "Enable support for Enhanced Privileged Access Never (EPAN)"
2138	default y
2139	depends on ARM64_PAN
2140	help
2141	  Enhanced Privileged Access Never (EPAN) allows Privileged
2142	  Access Never to be used with Execute-only mappings.
2143
2144	  The feature is detected at runtime, and will remain disabled
2145	  if the cpu does not implement the feature.
2146endmenu # "ARMv8.7 architectural features"
2147
2148config AS_HAS_MOPS
2149	def_bool $(as-instr,.arch_extension mops)
2150
2151menu "ARMv8.9 architectural features"
2152
2153config ARM64_POE
2154	prompt "Permission Overlay Extension"
2155	def_bool y
2156	select ARCH_USES_HIGH_VMA_FLAGS
2157	select ARCH_HAS_PKEYS
2158	help
2159	  The Permission Overlay Extension is used to implement Memory
2160	  Protection Keys. Memory Protection Keys provides a mechanism for
2161	  enforcing page-based protections, but without requiring modification
2162	  of the page tables when an application changes protection domains.
2163
2164	  For details, see Documentation/core-api/protection-keys.rst
2165
2166	  If unsure, say y.
2167
2168config ARCH_PKEY_BITS
2169	int
2170	default 3
2171
2172config ARM64_HAFT
2173	bool "Support for Hardware managed Access Flag for Table Descriptors"
2174	depends on ARM64_HW_AFDBM
2175	default y
2176	help
2177	  The ARMv8.9/ARMv9.5 introduces the feature Hardware managed Access
2178	  Flag for Table descriptors. When enabled an architectural executed
2179	  memory access will update the Access Flag in each Table descriptor
2180	  which is accessed during the translation table walk and for which
2181	  the Access Flag is 0. The Access Flag of the Table descriptor use
2182	  the same bit of PTE_AF.
2183
2184	  The feature will only be enabled if all the CPUs in the system
2185	  support this feature. If unsure, say Y.
2186
2187endmenu # "ARMv8.9 architectural features"
2188
2189menu "ARMv9.4 architectural features"
2190
2191config ARM64_GCS
2192	bool "Enable support for Guarded Control Stack (GCS)"
2193	default y
2194	select ARCH_HAS_USER_SHADOW_STACK
2195	select ARCH_USES_HIGH_VMA_FLAGS
2196	help
2197	  Guarded Control Stack (GCS) provides support for a separate
2198	  stack with restricted access which contains only return
2199	  addresses.  This can be used to harden against some attacks
2200	  by comparing return address used by the program with what is
2201	  stored in the GCS, and may also be used to efficiently obtain
2202	  the call stack for applications such as profiling.
2203
2204	  The feature is detected at runtime, and will remain disabled
2205	  if the system does not implement the feature.
2206
2207endmenu # "ARMv9.4 architectural features"
2208
2209config ARM64_SVE
2210	bool "ARM Scalable Vector Extension support"
2211	default y
2212	help
2213	  The Scalable Vector Extension (SVE) is an extension to the AArch64
2214	  execution state which complements and extends the SIMD functionality
2215	  of the base architecture to support much larger vectors and to enable
2216	  additional vectorisation opportunities.
2217
2218	  To enable use of this extension on CPUs that implement it, say Y.
2219
2220	  On CPUs that support the SVE2 extensions, this option will enable
2221	  those too.
2222
2223	  Note that for architectural reasons, firmware _must_ implement SVE
2224	  support when running on SVE capable hardware.  The required support
2225	  is present in:
2226
2227	    * version 1.5 and later of the ARM Trusted Firmware
2228	    * the AArch64 boot wrapper since commit 5e1261e08abf
2229	      ("bootwrapper: SVE: Enable SVE for EL2 and below").
2230
2231	  For other firmware implementations, consult the firmware documentation
2232	  or vendor.
2233
2234	  If you need the kernel to boot on SVE-capable hardware with broken
2235	  firmware, you may need to say N here until you get your firmware
2236	  fixed.  Otherwise, you may experience firmware panics or lockups when
2237	  booting the kernel.  If unsure and you are not observing these
2238	  symptoms, you should assume that it is safe to say Y.
2239
2240config ARM64_SME
2241	bool "ARM Scalable Matrix Extension support"
2242	default y
2243	depends on ARM64_SVE
2244	help
2245	  The Scalable Matrix Extension (SME) is an extension to the AArch64
2246	  execution state which utilises a substantial subset of the SVE
2247	  instruction set, together with the addition of new architectural
2248	  register state capable of holding two dimensional matrix tiles to
2249	  enable various matrix operations.
2250
2251config ARM64_PSEUDO_NMI
2252	bool "Support for NMI-like interrupts"
2253	select ARM_GIC_V3
2254	help
2255	  Adds support for mimicking Non-Maskable Interrupts through the use of
2256	  GIC interrupt priority. This support requires version 3 or later of
2257	  ARM GIC.
2258
2259	  This high priority configuration for interrupts needs to be
2260	  explicitly enabled by setting the kernel parameter
2261	  "irqchip.gicv3_pseudo_nmi" to 1.
2262
2263	  If unsure, say N
2264
2265if ARM64_PSEUDO_NMI
2266config ARM64_DEBUG_PRIORITY_MASKING
2267	bool "Debug interrupt priority masking"
2268	help
2269	  This adds runtime checks to functions enabling/disabling
2270	  interrupts when using priority masking. The additional checks verify
2271	  the validity of ICC_PMR_EL1 when calling concerned functions.
2272
2273	  If unsure, say N
2274endif # ARM64_PSEUDO_NMI
2275
2276config RELOCATABLE
2277	bool "Build a relocatable kernel image" if EXPERT
2278	select ARCH_HAS_RELR
2279	default y
2280	help
2281	  This builds the kernel as a Position Independent Executable (PIE),
2282	  which retains all relocation metadata required to relocate the
2283	  kernel binary at runtime to a different virtual address than the
2284	  address it was linked at.
2285	  Since AArch64 uses the RELA relocation format, this requires a
2286	  relocation pass at runtime even if the kernel is loaded at the
2287	  same address it was linked at.
2288
2289config RANDOMIZE_BASE
2290	bool "Randomize the address of the kernel image"
2291	select RELOCATABLE
2292	help
2293	  Randomizes the virtual address at which the kernel image is
2294	  loaded, as a security feature that deters exploit attempts
2295	  relying on knowledge of the location of kernel internals.
2296
2297	  It is the bootloader's job to provide entropy, by passing a
2298	  random u64 value in /chosen/kaslr-seed at kernel entry.
2299
2300	  When booting via the UEFI stub, it will invoke the firmware's
2301	  EFI_RNG_PROTOCOL implementation (if available) to supply entropy
2302	  to the kernel proper. In addition, it will randomise the physical
2303	  location of the kernel Image as well.
2304
2305	  If unsure, say N.
2306
2307config RANDOMIZE_MODULE_REGION_FULL
2308	bool "Randomize the module region over a 2 GB range"
2309	depends on RANDOMIZE_BASE
2310	default y
2311	help
2312	  Randomizes the location of the module region inside a 2 GB window
2313	  covering the core kernel. This way, it is less likely for modules
2314	  to leak information about the location of core kernel data structures
2315	  but it does imply that function calls between modules and the core
2316	  kernel will need to be resolved via veneers in the module PLT.
2317
2318	  When this option is not set, the module region will be randomized over
2319	  a limited range that contains the [_stext, _etext] interval of the
2320	  core kernel, so branch relocations are almost always in range unless
2321	  the region is exhausted. In this particular case of region
2322	  exhaustion, modules might be able to fall back to a larger 2GB area.
2323
2324config CC_HAVE_STACKPROTECTOR_SYSREG
2325	def_bool $(cc-option,-mstack-protector-guard=sysreg -mstack-protector-guard-reg=sp_el0 -mstack-protector-guard-offset=0)
2326
2327config STACKPROTECTOR_PER_TASK
2328	def_bool y
2329	depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_SYSREG
2330
2331config UNWIND_PATCH_PAC_INTO_SCS
2332	bool "Enable shadow call stack dynamically using code patching"
2333	# needs Clang with https://github.com/llvm/llvm-project/commit/de07cde67b5d205d58690be012106022aea6d2b3 incorporated
2334	depends on CC_IS_CLANG && CLANG_VERSION >= 150000
2335	depends on ARM64_PTR_AUTH_KERNEL && CC_HAS_BRANCH_PROT_PAC_RET
2336	depends on SHADOW_CALL_STACK
2337	select UNWIND_TABLES
2338	select DYNAMIC_SCS
2339
2340config ARM64_CONTPTE
2341	bool "Contiguous PTE mappings for user memory" if EXPERT
2342	depends on TRANSPARENT_HUGEPAGE
2343	default y
2344	help
2345	  When enabled, user mappings are configured using the PTE contiguous
2346	  bit, for any mappings that meet the size and alignment requirements.
2347	  This reduces TLB pressure and improves performance.
2348
2349endmenu # "Kernel Features"
2350
2351menu "Boot options"
2352
2353config ARM64_ACPI_PARKING_PROTOCOL
2354	bool "Enable support for the ARM64 ACPI parking protocol"
2355	depends on ACPI
2356	help
2357	  Enable support for the ARM64 ACPI parking protocol. If disabled
2358	  the kernel will not allow booting through the ARM64 ACPI parking
2359	  protocol even if the corresponding data is present in the ACPI
2360	  MADT table.
2361
2362config CMDLINE
2363	string "Default kernel command string"
2364	default ""
2365	help
2366	  Provide a set of default command-line options at build time by
2367	  entering them here. As a minimum, you should specify the the
2368	  root device (e.g. root=/dev/nfs).
2369
2370choice
2371	prompt "Kernel command line type"
2372	depends on CMDLINE != ""
2373	default CMDLINE_FROM_BOOTLOADER
2374	help
2375	  Choose how the kernel will handle the provided default kernel
2376	  command line string.
2377
2378config CMDLINE_FROM_BOOTLOADER
2379	bool "Use bootloader kernel arguments if available"
2380	help
2381	  Uses the command-line options passed by the boot loader. If
2382	  the boot loader doesn't provide any, the default kernel command
2383	  string provided in CMDLINE will be used.
2384
2385config CMDLINE_FORCE
2386	bool "Always use the default kernel command string"
2387	help
2388	  Always use the default kernel command string, even if the boot
2389	  loader passes other arguments to the kernel.
2390	  This is useful if you cannot or don't want to change the
2391	  command-line options your boot loader passes to the kernel.
2392
2393endchoice
2394
2395config EFI_STUB
2396	bool
2397
2398config EFI
2399	bool "UEFI runtime support"
2400	depends on OF && !CPU_BIG_ENDIAN
2401	depends on KERNEL_MODE_NEON
2402	select ARCH_SUPPORTS_ACPI
2403	select LIBFDT
2404	select UCS2_STRING
2405	select EFI_PARAMS_FROM_FDT
2406	select EFI_RUNTIME_WRAPPERS
2407	select EFI_STUB
2408	select EFI_GENERIC_STUB
2409	imply IMA_SECURE_AND_OR_TRUSTED_BOOT
2410	default y
2411	help
2412	  This option provides support for runtime services provided
2413	  by UEFI firmware (such as non-volatile variables, realtime
2414	  clock, and platform reset). A UEFI stub is also provided to
2415	  allow the kernel to be booted as an EFI application. This
2416	  is only useful on systems that have UEFI firmware.
2417
2418config COMPRESSED_INSTALL
2419	bool "Install compressed image by default"
2420	help
2421	  This makes the regular "make install" install the compressed
2422	  image we built, not the legacy uncompressed one.
2423
2424	  You can check that a compressed image works for you by doing
2425	  "make zinstall" first, and verifying that everything is fine
2426	  in your environment before making "make install" do this for
2427	  you.
2428
2429config DMI
2430	bool "Enable support for SMBIOS (DMI) tables"
2431	depends on EFI
2432	default y
2433	help
2434	  This enables SMBIOS/DMI feature for systems.
2435
2436	  This option is only useful on systems that have UEFI firmware.
2437	  However, even with this option, the resultant kernel should
2438	  continue to boot on existing non-UEFI platforms.
2439
2440endmenu # "Boot options"
2441
2442menu "Power management options"
2443
2444source "kernel/power/Kconfig"
2445
2446config ARCH_HIBERNATION_POSSIBLE
2447	def_bool y
2448	depends on CPU_PM
2449
2450config ARCH_HIBERNATION_HEADER
2451	def_bool y
2452	depends on HIBERNATION
2453
2454config ARCH_SUSPEND_POSSIBLE
2455	def_bool y
2456
2457endmenu # "Power management options"
2458
2459menu "CPU Power Management"
2460
2461source "drivers/cpuidle/Kconfig"
2462
2463source "drivers/cpufreq/Kconfig"
2464
2465endmenu # "CPU Power Management"
2466
2467source "drivers/acpi/Kconfig"
2468
2469source "arch/arm64/kvm/Kconfig"
2470
2471source "kernel/livepatch/Kconfig"
2472