xref: /linux/arch/arm64/Kconfig (revision 35e340a47888e3574ee4e8ef7da3f73a32034e58)
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_SPLIT_PMD_PTLOCK if PGTABLE_LEVELS > 2
20	select ARCH_HAS_PMD_SOFTLEAVES if TRANSPARENT_HUGEPAGE
21	select ARCH_HAS_CACHE_LINE_SIZE
22	select ARCH_HAS_CC_PLATFORM
23	select ARCH_HAS_CPU_CACHE_INVALIDATE_MEMREGION
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_LAZY_MMU_MODE
38	select ARCH_HAS_MEMBARRIER_SYNC_CORE
39	select ARCH_HAS_MEM_ENCRYPT
40	select ARCH_SUPPORTS_MSEAL_SYSTEM_MAPPINGS
41	select ARCH_HAS_NMI_SAFE_THIS_CPU_OPS
42	select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE
43	select ARCH_HAS_NONLEAF_PMD_YOUNG if ARM64_HAFT
44	select ARCH_HAS_PREEMPT_LAZY
45	select ARCH_HAS_PTDUMP
46	select ARCH_HAS_PTE_SPECIAL
47	select ARCH_HAS_HW_PTE_YOUNG
48	select ARCH_HAS_SETUP_DMA_OPS
49	select ARCH_HAS_SET_DIRECT_MAP
50	select ARCH_HAS_SET_MEMORY
51	select ARCH_HAS_FORCE_DMA_UNENCRYPTED
52	select ARCH_STACKWALK
53	select ARCH_HAS_STRICT_KERNEL_RWX
54	select ARCH_HAS_STRICT_MODULE_RWX
55	select ARCH_HAS_SYNC_DMA_FOR_DEVICE
56	select ARCH_HAS_SYNC_DMA_FOR_CPU
57	select ARCH_HAS_BATCHED_DMA_SYNC
58	select ARCH_HAS_SYSCALL_WRAPPER
59	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
60	select ARCH_HAS_ZONE_DMA_SET if EXPERT
61	select ARCH_HAVE_ELF_PROT
62	select ARCH_HAVE_NMI_SAFE_CMPXCHG
63	select ARCH_HAVE_TRACE_MMIO_ACCESS
64	select ARCH_KEEP_MEMBLOCK
65	select ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE
66	select ARCH_USE_CMPXCHG_LOCKREF
67	select ARCH_USE_GNU_PROPERTY
68	select ARCH_USE_MEMTEST
69	select ARCH_USE_QUEUED_RWLOCKS
70	select ARCH_USE_QUEUED_SPINLOCKS
71	select ARCH_USE_SYM_ANNOTATIONS
72	select ARCH_SUPPORTS_DEBUG_PAGEALLOC
73	select ARCH_SUPPORTS_HUGETLBFS
74	select ARCH_SUPPORTS_MEMORY_FAILURE
75	select ARCH_SUPPORTS_SHADOW_CALL_STACK if CC_HAVE_SHADOW_CALL_STACK
76	select ARCH_SUPPORTS_LTO_CLANG if CPU_LITTLE_ENDIAN
77	select ARCH_SUPPORTS_LTO_CLANG_THIN
78	select ARCH_SUPPORTS_CFI
79	select ARCH_SUPPORTS_ATOMIC_RMW
80	select ARCH_SUPPORTS_INT128 if CC_HAS_INT128
81	select ARCH_HAS_PTE_PROTNONE
82	select ARCH_SUPPORTS_NUMA_BALANCING
83	select ARCH_SUPPORTS_PAGE_TABLE_CHECK
84	select ARCH_SUPPORTS_HUGE_PFNMAP if TRANSPARENT_HUGEPAGE
85	select ARCH_SUPPORTS_RT
86	select ARCH_SUPPORTS_SCHED_SMT
87	select ARCH_SUPPORTS_SCHED_CLUSTER
88	select ARCH_SUPPORTS_SCHED_MC
89	select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH
90	select ARCH_WANT_COMPAT_IPC_PARSE_VERSION if COMPAT
91	select ARCH_WANT_DEFAULT_BPF_JIT
92	select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT
93	select ARCH_WANT_FRAME_POINTERS
94	select ARCH_WANT_HUGE_PMD_SHARE if ARM64_4K_PAGES || (ARM64_16K_PAGES && !ARM64_VA_BITS_36)
95	select ARCH_WANT_LD_ORPHAN_WARN
96	select ARCH_WANTS_EXECMEM_LATE
97	select ARCH_WANTS_NO_INSTR
98	select ARCH_WANTS_THP_SWAP if ARM64_4K_PAGES
99	select ARCH_HAS_UBSAN
100	select ARM_AMBA
101	select ARM_ARCH_TIMER
102	select ARM_GIC
103	select AUDIT_ARCH_COMPAT_GENERIC
104	select ARM_GIC_V2M if PCI
105	select ARM_GIC_V3
106	select ARM_GIC_V3_ITS if PCI
107	select ARM_GIC_V5
108	select ARM_PSCI_FW
109	select BUILDTIME_TABLE_SORT
110	select CLONE_BACKWARDS
111	select COMMON_CLK
112	select CPU_PM if (SUSPEND || CPU_IDLE)
113	select CPUMASK_OFFSTACK if NR_CPUS > 256
114	select DCACHE_WORD_ACCESS
115	select HAVE_EXTRA_IPI_TRACEPOINTS
116	select DYNAMIC_FTRACE if FUNCTION_TRACER
117	select DMA_BOUNCE_UNALIGNED_KMALLOC
118	select DMA_DIRECT_REMAP
119	select EDAC_SUPPORT
120	select FRAME_POINTER
121	select FUNCTION_ALIGNMENT_4B
122	select FUNCTION_ALIGNMENT_8B if DYNAMIC_FTRACE_WITH_CALL_OPS
123	select GENERIC_ALLOCATOR
124	select GENERIC_ARCH_TOPOLOGY
125	select GENERIC_CLOCKEVENTS_BROADCAST
126	select GENERIC_CPU_AUTOPROBE
127	select GENERIC_CPU_CACHE_MAINTENANCE
128	select GENERIC_CPU_DEVICES
129	select GENERIC_CPU_VULNERABILITIES
130	select GENERIC_EARLY_IOREMAP
131	select GENERIC_IDLE_POLL_SETUP
132	select GENERIC_IOREMAP
133	select GENERIC_IRQ_ENTRY
134	select GENERIC_IRQ_IPI
135	select GENERIC_IRQ_KEXEC_CLEAR_VM_FORWARD
136	select GENERIC_IRQ_PROBE
137	select GENERIC_IRQ_SHOW
138	select GENERIC_IRQ_SHOW_LEVEL
139	select GENERIC_LIB_DEVMEM_IS_ALLOWED
140	select GENERIC_PCI_IOMAP
141	select GENERIC_SCHED_CLOCK
142	select GENERIC_SMP_IDLE_THREAD
143	select GENERIC_GETTIMEOFDAY
144	select HARDIRQS_SW_RESEND
145	select HAS_IOPORT
146	select HAVE_MOVE_PMD
147	select HAVE_MOVE_PUD
148	select HAVE_PCI
149	select HAVE_ACPI_APEI if (ACPI && EFI)
150	select HAVE_ALIGNED_STRUCT_PAGE
151	select HAVE_ARCH_AUDITSYSCALL
152	select HAVE_ARCH_BITREVERSE if BITREVERSE
153	select HAVE_ARCH_COMPILER_H
154	select HAVE_ARCH_HUGE_VMALLOC
155	select HAVE_ARCH_HUGE_VMAP
156	select HAVE_ARCH_JUMP_LABEL
157	select HAVE_ARCH_JUMP_LABEL_RELATIVE
158	select HAVE_ARCH_KASAN
159	select HAVE_ARCH_KASAN_VMALLOC
160	select HAVE_ARCH_KASAN_SW_TAGS
161	select HAVE_ARCH_KASAN_HW_TAGS if ARM64_MTE
162	# Some instrumentation may be unsound, hence EXPERT
163	select HAVE_ARCH_KCSAN if EXPERT
164	select HAVE_ARCH_KFENCE
165	select HAVE_ARCH_KGDB
166	select HAVE_ARCH_KSTACK_ERASE
167	select HAVE_ARCH_MMAP_RND_BITS
168	select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT
169	select HAVE_ARCH_PREL32_RELOCATIONS
170	select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET
171	select HAVE_ARCH_SECCOMP_FILTER
172	select HAVE_ARCH_THREAD_STRUCT_WHITELIST
173	select HAVE_ARCH_TRACEHOOK
174	select HAVE_ARCH_TRANSPARENT_HUGEPAGE
175	select HAVE_ARCH_VMAP_STACK
176	select HAVE_ARM_SMCCC
177	select HAVE_ASM_MODVERSIONS
178	select HAVE_EBPF_JIT
179	select HAVE_C_RECORDMCOUNT
180	select HAVE_CMPXCHG_DOUBLE
181	select HAVE_CMPXCHG_LOCAL
182	select HAVE_CONTEXT_TRACKING_USER
183	select HAVE_DEBUG_KMEMLEAK
184	select HAVE_DMA_CONTIGUOUS
185	select HAVE_DYNAMIC_FTRACE
186	select HAVE_DYNAMIC_FTRACE_WITH_ARGS \
187		if (GCC_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS || \
188		    CLANG_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS)
189	select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS \
190		if DYNAMIC_FTRACE_WITH_ARGS
191	select HAVE_DYNAMIC_FTRACE_WITH_CALL_OPS \
192		if (DYNAMIC_FTRACE_WITH_ARGS && !CFI && \
193		    (CC_IS_CLANG || !CC_OPTIMIZE_FOR_SIZE))
194	select FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY \
195		if DYNAMIC_FTRACE_WITH_ARGS
196	select HAVE_SAMPLE_FTRACE_DIRECT
197	select HAVE_SAMPLE_FTRACE_DIRECT_MULTI
198	select HAVE_BUILDTIME_MCOUNT_SORT
199	select HAVE_EFFICIENT_UNALIGNED_ACCESS
200	select HAVE_GUP_FAST
201	select HAVE_FTRACE_GRAPH_FUNC
202	select HAVE_FUNCTION_TRACER
203	select HAVE_FUNCTION_ERROR_INJECTION
204	select HAVE_FUNCTION_GRAPH_FREGS
205	select HAVE_FUNCTION_GRAPH_TRACER
206	select HAVE_GCC_PLUGINS
207	select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && \
208		HW_PERF_EVENTS && HAVE_PERF_EVENTS_NMI
209	select HAVE_HW_BREAKPOINT if PERF_EVENTS
210	select HAVE_IOREMAP_PROT
211	select HAVE_IRQ_TIME_ACCOUNTING
212	select HAVE_LIVEPATCH
213	select HAVE_MOD_ARCH_SPECIFIC
214	select HAVE_NMI
215	select HAVE_PERF_EVENTS
216	select HAVE_PERF_EVENTS_NMI if ARM64_PSEUDO_NMI
217	select HAVE_PERF_REGS
218	select HAVE_PERF_USER_STACK_DUMP
219	select HAVE_PREEMPT_DYNAMIC_KEY
220	select HAVE_REGS_AND_STACK_ACCESS_API
221	select HAVE_RELIABLE_STACKTRACE
222	select HAVE_POSIX_CPU_TIMERS_TASK_WORK
223	select HAVE_FUNCTION_ARG_ACCESS_API
224	select HAVE_RSEQ
225	select HAVE_RUST if RUSTC_SUPPORTS_ARM64
226	select HAVE_STACKPROTECTOR
227	select HAVE_STATIC_CALL if CFI
228	select HAVE_SYSCALL_TRACEPOINTS
229	select HAVE_KPROBES
230	select HAVE_KRETPROBES
231	select HOTPLUG_CORE_SYNC_DEAD if HOTPLUG_CPU
232	select HOTPLUG_SMT if HOTPLUG_CPU
233	select IRQ_DOMAIN
234	select IRQ_FORCED_THREADING
235	select JUMP_LABEL
236	select KASAN_VMALLOC if KASAN
237	select LOCK_MM_AND_FIND_VMA
238	select MODULES_USE_ELF_RELA
239	select NEED_DMA_MAP_STATE
240	select NEED_SG_DMA_LENGTH
241	select OF
242	select OF_EARLY_FLATTREE
243	select PCI_DOMAINS_GENERIC if PCI
244	select PCI_ECAM if (ACPI && PCI)
245	select PCI_SYSCALL if PCI
246	select POWER_RESET
247	select POWER_SUPPLY
248	select HAS_SEPARATE_PREEMPT_RESCHED_BITS
249	select SPARSE_IRQ
250	select SWIOTLB
251	select SYSCTL_EXCEPTION_TRACE
252	select THREAD_INFO_IN_TASK
253	select HAVE_ARCH_USERFAULTFD_MINOR if USERFAULTFD
254	select HAVE_ARCH_USERFAULTFD_WP if USERFAULTFD
255	select TRACE_IRQFLAGS_SUPPORT
256	select TRACE_IRQFLAGS_NMI_SUPPORT
257	select HAVE_SOFTIRQ_ON_OWN_STACK
258	select USER_STACKTRACE_SUPPORT
259	select VDSO_GETRANDOM
260	select VMAP_STACK
261	help
262	  ARM 64-bit (AArch64) Linux support.
263
264config RUSTC_SUPPORTS_ARM64
265	def_bool y
266	depends on CPU_LITTLE_ENDIAN
267
268config CLANG_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS
269	def_bool CC_IS_CLANG
270	# https://github.com/ClangBuiltLinux/linux/issues/1507
271	depends on AS_IS_GNU || (AS_IS_LLVM && (LD_IS_LLD || LD_VERSION >= 23600))
272
273config GCC_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS
274	def_bool CC_IS_GCC
275	depends on $(cc-option,-fpatchable-function-entry=2)
276
277config 64BIT
278	def_bool y
279
280config MMU
281	def_bool y
282
283config ARM64_CONT_PTE_SHIFT
284	int
285	default 5 if PAGE_SIZE_64KB
286	default 7 if PAGE_SIZE_16KB
287	default 4
288
289config ARM64_CONT_PMD_SHIFT
290	int
291	default 5 if PAGE_SIZE_64KB
292	default 5 if PAGE_SIZE_16KB
293	default 4
294
295config ARCH_MMAP_RND_BITS_MIN
296	default 14 if PAGE_SIZE_64KB
297	default 16 if PAGE_SIZE_16KB
298	default 18
299
300# max bits determined by the following formula:
301#  VA_BITS - PTDESC_TABLE_SHIFT
302config ARCH_MMAP_RND_BITS_MAX
303	default 19 if ARM64_VA_BITS=36
304	default 24 if ARM64_VA_BITS=39
305	default 27 if ARM64_VA_BITS=42
306	default 30 if ARM64_VA_BITS=47
307	default 29 if (ARM64_VA_BITS=48 || ARM64_VA_BITS=52) && ARM64_64K_PAGES
308	default 31 if (ARM64_VA_BITS=48 || ARM64_VA_BITS=52) && ARM64_16K_PAGES
309	default 33 if (ARM64_VA_BITS=48 || ARM64_VA_BITS=52)
310	default 14 if ARM64_64K_PAGES
311	default 16 if ARM64_16K_PAGES
312	default 18
313
314config ARCH_MMAP_RND_COMPAT_BITS_MIN
315	default 7 if ARM64_64K_PAGES
316	default 9 if ARM64_16K_PAGES
317	default 11
318
319config ARCH_MMAP_RND_COMPAT_BITS_MAX
320	default 16
321
322config NO_IOPORT_MAP
323	def_bool y if !PCI
324
325config STACKTRACE_SUPPORT
326	def_bool y
327
328config ILLEGAL_POINTER_VALUE
329	hex
330	default 0xdead000000000000
331
332config LOCKDEP_SUPPORT
333	def_bool y
334
335config GENERIC_BUG
336	def_bool y
337	depends on BUG
338
339config GENERIC_BUG_RELATIVE_POINTERS
340	def_bool y
341	depends on GENERIC_BUG
342
343config GENERIC_HWEIGHT
344	def_bool y
345
346config GENERIC_CSUM
347	def_bool y
348
349config GENERIC_CALIBRATE_DELAY
350	def_bool y
351
352config SMP
353	def_bool y
354
355config KERNEL_MODE_NEON
356	def_bool y
357
358config FIX_EARLYCON_MEM
359	def_bool y
360
361config PGTABLE_LEVELS
362	int
363	default 2 if ARM64_16K_PAGES && ARM64_VA_BITS_36
364	default 2 if ARM64_64K_PAGES && ARM64_VA_BITS_42
365	default 3 if ARM64_64K_PAGES && (ARM64_VA_BITS_48 || ARM64_VA_BITS_52)
366	default 3 if ARM64_4K_PAGES && ARM64_VA_BITS_39
367	default 3 if ARM64_16K_PAGES && ARM64_VA_BITS_47
368	default 4 if ARM64_16K_PAGES && (ARM64_VA_BITS_48 || ARM64_VA_BITS_52)
369	default 4 if !ARM64_64K_PAGES && ARM64_VA_BITS_48
370	default 5 if ARM64_4K_PAGES && ARM64_VA_BITS_52
371
372config ARCH_SUPPORTS_UPROBES
373	def_bool y
374
375config ARCH_PROC_KCORE_TEXT
376	def_bool y
377
378config BROKEN_GAS_INST
379	def_bool !$(as-instr,1:\n.inst 0\n.rept . - 1b\n\nnop\n.endr\n)
380
381config BUILTIN_RETURN_ADDRESS_STRIPS_PAC
382	bool
383	# Clang's __builtin_return_address() strips the PAC since 12.0.0
384	# https://github.com/llvm/llvm-project/commit/2a96f47c5ffca84cd774ad402cacd137f4bf45e2
385	default y if CC_IS_CLANG
386	# GCC's __builtin_return_address() strips the PAC since 11.1.0,
387	# and this was backported to 10.2.0, 9.4.0, 8.5.0, but not earlier
388	# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94891
389	default y if CC_IS_GCC && (GCC_VERSION >= 110100)
390	default y if CC_IS_GCC && (GCC_VERSION >= 100200) && (GCC_VERSION < 110000)
391	default y if CC_IS_GCC && (GCC_VERSION >=  90400) && (GCC_VERSION < 100000)
392	default y if CC_IS_GCC && (GCC_VERSION >=  80500) && (GCC_VERSION <  90000)
393	default n
394
395config KASAN_SHADOW_OFFSET
396	hex
397	depends on KASAN_GENERIC || KASAN_SW_TAGS
398	default 0xdfff800000000000 if (ARM64_VA_BITS_48 || (ARM64_VA_BITS_52 && !ARM64_16K_PAGES)) && !KASAN_SW_TAGS
399	default 0xdfffc00000000000 if (ARM64_VA_BITS_47 || ARM64_VA_BITS_52) && ARM64_16K_PAGES && !KASAN_SW_TAGS
400	default 0xdffffe0000000000 if ARM64_VA_BITS_42 && !KASAN_SW_TAGS
401	default 0xdfffffc000000000 if ARM64_VA_BITS_39 && !KASAN_SW_TAGS
402	default 0xdffffff800000000 if ARM64_VA_BITS_36 && !KASAN_SW_TAGS
403	default 0xefff800000000000 if (ARM64_VA_BITS_48 || (ARM64_VA_BITS_52 && !ARM64_16K_PAGES)) && KASAN_SW_TAGS
404	default 0xefffc00000000000 if (ARM64_VA_BITS_47 || ARM64_VA_BITS_52) && ARM64_16K_PAGES && KASAN_SW_TAGS
405	default 0xeffffe0000000000 if ARM64_VA_BITS_42 && KASAN_SW_TAGS
406	default 0xefffffc000000000 if ARM64_VA_BITS_39 && KASAN_SW_TAGS
407	default 0xeffffff800000000 if ARM64_VA_BITS_36 && KASAN_SW_TAGS
408	default 0xffffffffffffffff
409
410config UNWIND_TABLES
411	bool
412
413source "arch/arm64/Kconfig.platforms"
414
415menu "Kernel Features"
416
417menu "ARM errata workarounds via the alternatives framework"
418
419config AMPERE_ERRATUM_AC03_CPU_38
420        bool "AmpereOne: AC03_CPU_38: Certain bits in the Virtualization Translation Control Register and Translation Control Registers do not follow RES0 semantics"
421	default y
422	help
423	  This option adds an alternative code sequence to work around Ampere
424	  errata AC03_CPU_38 and AC04_CPU_10 on AmpereOne.
425
426	  The affected design reports FEAT_HAFDBS as not implemented in
427	  ID_AA64MMFR1_EL1.HAFDBS, but (V)TCR_ELx.{HA,HD} are not RES0
428	  as required by the architecture. The unadvertised HAFDBS
429	  implementation suffers from an additional erratum where hardware
430	  A/D updates can occur after a PTE has been marked invalid.
431
432	  The workaround forces KVM to explicitly set VTCR_EL2.HA to 0,
433	  which avoids enabling unadvertised hardware Access Flag management
434	  at stage-2.
435
436	  If unsure, say Y.
437
438config AMPERE_ERRATUM_AC04_CPU_23
439        bool "AmpereOne: AC04_CPU_23:  Failure to synchronize writes to HCR_EL2 may corrupt address translations."
440	default y
441	help
442	  This option adds an alternative code sequence to work around Ampere
443	  errata AC04_CPU_23 on AmpereOne.
444
445	  Updates to HCR_EL2 can rarely corrupt simultaneous translations for
446	  data addresses initiated by load/store instructions. Only
447	  instruction initiated translations are vulnerable, not translations
448	  from prefetches for example. A DSB before the store to HCR_EL2 is
449	  sufficient to prevent older instructions from hitting the window
450	  for corruption, and an ISB after is sufficient to prevent younger
451	  instructions from hitting the window for corruption.
452
453	  If unsure, say Y.
454
455config ARM64_WORKAROUND_CLEAN_CACHE
456	bool
457
458config ARM64_ERRATUM_826319
459	bool "Cortex-A53: 826319: System might deadlock if a write cannot complete until read data is accepted"
460	default y
461	select ARM64_WORKAROUND_CLEAN_CACHE
462	help
463	  This option adds an alternative code sequence to work around ARM
464	  erratum 826319 on Cortex-A53 parts up to r0p2 with an AMBA 4 ACE or
465	  AXI master interface and an L2 cache.
466
467	  If a Cortex-A53 uses an AMBA AXI4 ACE interface to other processors
468	  and is unable to accept a certain write via this interface, it will
469	  not progress on read data presented on the read data channel and the
470	  system can deadlock.
471
472	  The workaround promotes data cache clean instructions to
473	  data cache clean-and-invalidate.
474	  Please note that this does not necessarily enable the workaround,
475	  as it depends on the alternative framework, which will only patch
476	  the kernel if an affected CPU is detected.
477
478	  If unsure, say Y.
479
480config ARM64_ERRATUM_827319
481	bool "Cortex-A53: 827319: Data cache clean instructions might cause overlapping transactions to the interconnect"
482	default y
483	select ARM64_WORKAROUND_CLEAN_CACHE
484	help
485	  This option adds an alternative code sequence to work around ARM
486	  erratum 827319 on Cortex-A53 parts up to r0p2 with an AMBA 5 CHI
487	  master interface and an L2 cache.
488
489	  Under certain conditions this erratum can cause a clean line eviction
490	  to occur at the same time as another transaction to the same address
491	  on the AMBA 5 CHI interface, which can cause data corruption if the
492	  interconnect reorders the two transactions.
493
494	  The workaround promotes data cache clean instructions to
495	  data cache clean-and-invalidate.
496	  Please note that this does not necessarily enable the workaround,
497	  as it depends on the alternative framework, which will only patch
498	  the kernel if an affected CPU is detected.
499
500	  If unsure, say Y.
501
502config ARM64_ERRATUM_824069
503	bool "Cortex-A53: 824069: Cache line might not be marked as clean after a CleanShared snoop"
504	default y
505	select ARM64_WORKAROUND_CLEAN_CACHE
506	help
507	  This option adds an alternative code sequence to work around ARM
508	  erratum 824069 on Cortex-A53 parts up to r0p2 when it is connected
509	  to a coherent interconnect.
510
511	  If a Cortex-A53 processor is executing a store or prefetch for
512	  write instruction at the same time as a processor in another
513	  cluster is executing a cache maintenance operation to the same
514	  address, then this erratum might cause a clean cache line to be
515	  incorrectly marked as dirty.
516
517	  The workaround promotes data cache clean instructions to
518	  data cache clean-and-invalidate.
519	  Please note that this option does not necessarily enable the
520	  workaround, as it depends on the alternative framework, which will
521	  only patch the kernel if an affected CPU is detected.
522
523	  If unsure, say Y.
524
525config ARM64_ERRATUM_819472
526	bool "Cortex-A53: 819472: Store exclusive instructions might cause data corruption"
527	default y
528	select ARM64_WORKAROUND_CLEAN_CACHE
529	help
530	  This option adds an alternative code sequence to work around ARM
531	  erratum 819472 on Cortex-A53 parts up to r0p1 with an L2 cache
532	  present when it is connected to a coherent interconnect.
533
534	  If the processor is executing a load and store exclusive sequence at
535	  the same time as a processor in another cluster is executing a cache
536	  maintenance operation to the same address, then this erratum might
537	  cause data corruption.
538
539	  The workaround promotes data cache clean instructions to
540	  data cache clean-and-invalidate.
541	  Please note that this does not necessarily enable the workaround,
542	  as it depends on the alternative framework, which will only patch
543	  the kernel if an affected CPU is detected.
544
545	  If unsure, say Y.
546
547config ARM64_ERRATUM_832075
548	bool "Cortex-A57: 832075: possible deadlock on mixing exclusive memory accesses with device loads"
549	default y
550	help
551	  This option adds an alternative code sequence to work around ARM
552	  erratum 832075 on Cortex-A57 parts up to r1p2.
553
554	  Affected Cortex-A57 parts might deadlock when exclusive load/store
555	  instructions to Write-Back memory are mixed with Device loads.
556
557	  The workaround is to promote device loads to use Load-Acquire
558	  semantics.
559	  Please note that this does not necessarily enable the workaround,
560	  as it depends on the alternative framework, which will only patch
561	  the kernel if an affected CPU is detected.
562
563	  If unsure, say Y.
564
565config ARM64_ERRATUM_834220
566	bool "Cortex-A57: 834220: Stage 2 translation fault might be incorrectly reported in presence of a Stage 1 fault (rare)"
567	depends on KVM
568	help
569	  This option adds an alternative code sequence to work around ARM
570	  erratum 834220 on Cortex-A57 parts up to r1p2.
571
572	  Affected Cortex-A57 parts might report a Stage 2 translation
573	  fault as the result of a Stage 1 fault for load crossing a
574	  page boundary when there is a permission or device memory
575	  alignment fault at Stage 1 and a translation fault at Stage 2.
576
577	  The workaround is to verify that the Stage 1 translation
578	  doesn't generate a fault before handling the Stage 2 fault.
579	  Please note that this does not necessarily enable the workaround,
580	  as it depends on the alternative framework, which will only patch
581	  the kernel if an affected CPU is detected.
582
583	  If unsure, say N.
584
585config ARM64_ERRATUM_1742098
586	bool "Cortex-A57/A72: 1742098: ELR recorded incorrectly on interrupt taken between cryptographic instructions in a sequence"
587	depends on COMPAT
588	default y
589	help
590	  This option removes the AES hwcap for aarch32 user-space to
591	  workaround erratum 1742098 on Cortex-A57 and Cortex-A72.
592
593	  Affected parts may corrupt the AES state if an interrupt is
594	  taken between a pair of AES instructions. These instructions
595	  are only present if the cryptography extensions are present.
596	  All software should have a fallback implementation for CPUs
597	  that don't implement the cryptography extensions.
598
599	  If unsure, say Y.
600
601config ARM64_ERRATUM_845719
602	bool "Cortex-A53: 845719: a load might read incorrect data"
603	depends on COMPAT
604	default y
605	help
606	  This option adds an alternative code sequence to work around ARM
607	  erratum 845719 on Cortex-A53 parts up to r0p4.
608
609	  When running a compat (AArch32) userspace on an affected Cortex-A53
610	  part, a load at EL0 from a virtual address that matches the bottom 32
611	  bits of the virtual address used by a recent load at (AArch64) EL1
612	  might return incorrect data.
613
614	  The workaround is to write the contextidr_el1 register on exception
615	  return to a 32-bit task.
616	  Please note that this does not necessarily enable the workaround,
617	  as it depends on the alternative framework, which will only patch
618	  the kernel if an affected CPU is detected.
619
620	  If unsure, say Y.
621
622config ARM64_ERRATUM_843419
623	bool "Cortex-A53: 843419: A load or store might access an incorrect address"
624	default y
625	help
626	  This option links the kernel with '--fix-cortex-a53-843419' and
627	  enables PLT support to replace certain ADRP instructions, which can
628	  cause subsequent memory accesses to use an incorrect address on
629	  Cortex-A53 parts up to r0p4.
630
631	  If unsure, say Y.
632
633config ARM64_ERRATUM_1024718
634	bool "Cortex-A55: 1024718: Update of DBM/AP bits without break before make might result in incorrect update"
635	default y
636	help
637	  This option adds a workaround for ARM Cortex-A55 Erratum 1024718.
638
639	  Affected Cortex-A55 cores (all revisions) could cause incorrect
640	  update of the hardware dirty bit when the DBM/AP bits are updated
641	  without a break-before-make. The workaround is to disable the usage
642	  of hardware DBM locally on the affected cores. CPUs not affected by
643	  this erratum will continue to use the feature.
644
645	  If unsure, say Y.
646
647config ARM64_ERRATUM_1418040
648	bool "Cortex-A76/Neoverse-N1: MRC read following MRRC read of specific Generic Timer in AArch32 might give incorrect result"
649	default y
650	depends on COMPAT
651	help
652	  This option adds a workaround for ARM Cortex-A76/Neoverse-N1
653	  errata 1188873 and 1418040.
654
655	  Affected Cortex-A76/Neoverse-N1 cores (r0p0 to r3p1) could
656	  cause register corruption when accessing the timer registers
657	  from AArch32 userspace.
658
659	  If unsure, say Y.
660
661config ARM64_WORKAROUND_SPECULATIVE_AT
662	bool
663
664config ARM64_ERRATUM_1165522
665	bool "Cortex-A76: 1165522: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
666	default y
667	select ARM64_WORKAROUND_SPECULATIVE_AT
668	help
669	  This option adds a workaround for ARM Cortex-A76 erratum 1165522.
670
671	  Affected Cortex-A76 cores (r0p0, r1p0, r2p0) could end-up with
672	  corrupted TLBs by speculating an AT instruction during a guest
673	  context switch.
674
675	  If unsure, say Y.
676
677config ARM64_ERRATUM_1319367
678	bool "Cortex-A57/A72: 1319537: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
679	default y
680	select ARM64_WORKAROUND_SPECULATIVE_AT
681	help
682	  This option adds work arounds for ARM Cortex-A57 erratum 1319537
683	  and A72 erratum 1319367
684
685	  Cortex-A57 and A72 cores could end-up with corrupted TLBs by
686	  speculating an AT instruction during a guest context switch.
687
688	  If unsure, say Y.
689
690config ARM64_ERRATUM_1530923
691	bool "Cortex-A55: 1530923: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
692	default y
693	select ARM64_WORKAROUND_SPECULATIVE_AT
694	help
695	  This option adds a workaround for ARM Cortex-A55 erratum 1530923.
696
697	  Affected Cortex-A55 cores (r0p0, r0p1, r1p0, r2p0) could end-up with
698	  corrupted TLBs by speculating an AT instruction during a guest
699	  context switch.
700
701	  If unsure, say Y.
702
703config ARM64_WORKAROUND_REPEAT_TLBI_SYNC
704	bool
705	# This workaround is (only) suitable for TLB invalidation errata where
706	# all of the following conditions are true:
707	#
708	# - The effects of the errata are only a loss of ordering/completion
709	#   for explicit memory accesses when the TLBI is completed with a DSB.
710	#   The removal of TLB entries is not affected.
711	#
712	#   Note that architecturally, S2-only invalidation does not remove
713	#   combined S1+S2 entries, and does not complete accesses translated
714	#   via those S1+S2 entries. Consequently, where this condition holds,
715	#   the errata do not affect S2-only invalidation.
716	#
717	# - The errata only affect broadcast TLB invalidation operations (e.g.
718	#   TLBI VMALLE1IS), and do not affect local TLB invalidation
719	#   operations (e.g. TLBI VMALLE1).
720	#
721	# - After any number of affected TLBI operations are completed with a
722	#   DSB, the errata can be mitigated by executing a single arbitrary
723	#   broadcast TLBI (which targets an arbitrary translation regime),
724	#   followed by a DSB.
725	#
726	# For more rationale, see commit a8f78680ee6bf795.
727
728config ARM64_ERRATUM_2441007
729	bool "Cortex-A55: Completion of affected memory accesses might not be guaranteed by completion of a TLBI (rare)"
730	select ARM64_WORKAROUND_REPEAT_TLBI_SYNC
731	help
732	  This option adds a workaround for ARM Cortex-A55 erratum #2441007.
733
734	  Under very rare circumstances, affected Cortex-A55 CPUs
735	  may not handle a race between a break-before-make sequence on one
736	  CPU, and another CPU accessing the same page. This could allow a
737	  store to a page that has been unmapped.
738
739	  Work around this by adding the affected CPUs to the list that needs
740	  TLB sequences to be done twice.
741
742	  If unsure, say N.
743
744config ARM64_ERRATUM_1286807
745	bool "Cortex-A76: Modification of the translation table for a virtual address might lead to read-after-read ordering violation (rare)"
746	select ARM64_WORKAROUND_REPEAT_TLBI_SYNC
747	help
748	  This option adds a workaround for ARM Cortex-A76 erratum 1286807.
749
750	  On the affected Cortex-A76 cores (r0p0 to r3p0), if a virtual
751	  address for a cacheable mapping of a location is being
752	  accessed by a core while another core is remapping the virtual
753	  address to a new physical page using the recommended
754	  break-before-make sequence, then under very rare circumstances
755	  TLBI+DSB completes before a read using the translation being
756	  invalidated has been observed by other observers. The
757	  workaround repeats the TLBI+DSB operation.
758
759	  If unsure, say N.
760
761config ARM64_ERRATUM_1463225
762	bool "Cortex-A76: Software Step might prevent interrupt recognition"
763	default y
764	help
765	  This option adds a workaround for Arm Cortex-A76 erratum 1463225.
766
767	  On the affected Cortex-A76 cores (r0p0 to r3p1), software stepping
768	  of a system call instruction (SVC) can prevent recognition of
769	  subsequent interrupts when software stepping is disabled in the
770	  exception handler of the system call and either kernel debugging
771	  is enabled or VHE is in use.
772
773	  Work around the erratum by triggering a dummy step exception
774	  when handling a system call from a task that is being stepped
775	  in a VHE configuration of the kernel.
776
777	  If unsure, say Y.
778
779config ARM64_ERRATUM_1542419
780	bool "Neoverse-N1: workaround mis-ordering of instruction fetches (rare)"
781	help
782	  This option adds a workaround for ARM Neoverse-N1 erratum
783	  1542419.
784
785	  Affected Neoverse-N1 cores could execute a stale instruction when
786	  modified by another CPU. The workaround depends on a firmware
787	  counterpart.
788
789	  Workaround the issue by hiding the DIC feature from EL0. This
790	  forces user-space to perform cache maintenance.
791
792	  If unsure, say N.
793
794config ARM64_ERRATUM_1508412
795	bool "Cortex-A77: 1508412: workaround deadlock on sequence of NC/Device load and store exclusive or PAR read"
796	default y
797	help
798	  This option adds a workaround for Arm Cortex-A77 erratum 1508412.
799
800	  Affected Cortex-A77 cores (r0p0, r1p0) could deadlock on a sequence
801	  of a store-exclusive or read of PAR_EL1 and a load with device or
802	  non-cacheable memory attributes. The workaround depends on a firmware
803	  counterpart.
804
805	  KVM guests must also have the workaround implemented or they can
806	  deadlock the system.
807
808	  Work around the issue by inserting DMB SY barriers around PAR_EL1
809	  register reads and warning KVM users. The DMB barrier is sufficient
810	  to prevent a speculative PAR_EL1 read.
811
812	  If unsure, say Y.
813
814config ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
815	bool
816
817config ARM64_ERRATUM_2051678
818	bool "Cortex-A510: 2051678: disable Hardware Update of the page table dirty bit"
819	default y
820	help
821	  This options adds the workaround for ARM Cortex-A510 erratum ARM64_ERRATUM_2051678.
822	  Affected Cortex-A510 might not respect the ordering rules for
823	  hardware update of the page table's dirty bit. The workaround
824	  is to not enable the feature on affected CPUs.
825
826	  If unsure, say Y.
827
828config ARM64_ERRATUM_2077057
829	bool "Cortex-A510: 2077057: workaround software-step corrupting SPSR_EL2"
830	default y
831	help
832	  This option adds the workaround for ARM Cortex-A510 erratum 2077057.
833	  Affected Cortex-A510 may corrupt SPSR_EL2 when the a step exception is
834	  expected, but a Pointer Authentication trap is taken instead. The
835	  erratum causes SPSR_EL1 to be copied to SPSR_EL2, which could allow
836	  EL1 to cause a return to EL2 with a guest controlled ELR_EL2.
837
838	  This can only happen when EL2 is stepping EL1.
839
840	  When these conditions occur, the SPSR_EL2 value is unchanged from the
841	  previous guest entry, and can be restored from the in-memory copy.
842
843	  If unsure, say Y.
844
845config ARM64_ERRATUM_2658417
846	bool "Cortex-A510: 2658417: remove BF16 support due to incorrect result"
847	default y
848	help
849	  This option adds the workaround for ARM Cortex-A510 erratum 2658417.
850	  Affected Cortex-A510 (r0p0 to r1p1) may produce the wrong result for
851	  BFMMLA or VMMLA instructions in rare circumstances when a pair of
852	  A510 CPUs are using shared neon hardware. As the sharing is not
853	  discoverable by the kernel, hide the BF16 HWCAP to indicate that
854	  user-space should not be using these instructions.
855
856	  If unsure, say Y.
857
858config ARM64_ERRATUM_2119858
859	bool "Cortex-A710/X2: 2119858: workaround TRBE overwriting trace data in FILL mode"
860	default y
861	depends on CORESIGHT_TRBE
862	select ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
863	help
864	  This option adds the workaround for ARM Cortex-A710/X2 erratum 2119858.
865
866	  Affected Cortex-A710/X2 cores could overwrite up to 3 cache lines of trace
867	  data at the base of the buffer (pointed to by TRBASER_EL1) in FILL mode in
868	  the event of a WRAP event.
869
870	  Work around the issue by always making sure we move the TRBPTR_EL1 by
871	  256 bytes before enabling the buffer and filling the first 256 bytes of
872	  the buffer with ETM ignore packets upon disabling.
873
874	  If unsure, say Y.
875
876config ARM64_ERRATUM_2139208
877	bool "Neoverse-N2: 2139208: workaround TRBE overwriting trace data in FILL mode"
878	default y
879	depends on CORESIGHT_TRBE
880	select ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE
881	help
882	  This option adds the workaround for ARM Neoverse-N2 erratum 2139208.
883
884	  Affected Neoverse-N2 cores could overwrite up to 3 cache lines of trace
885	  data at the base of the buffer (pointed to by TRBASER_EL1) in FILL mode in
886	  the event of a WRAP event.
887
888	  Work around the issue by always making sure we move the TRBPTR_EL1 by
889	  256 bytes before enabling the buffer and filling the first 256 bytes of
890	  the buffer with ETM ignore packets upon disabling.
891
892	  If unsure, say Y.
893
894config ARM64_WORKAROUND_TSB_FLUSH_FAILURE
895	bool
896
897config ARM64_ERRATUM_2054223
898	bool "Cortex-A710: 2054223: workaround TSB instruction failing to flush trace"
899	default y
900	select ARM64_WORKAROUND_TSB_FLUSH_FAILURE
901	help
902	  Enable workaround for ARM Cortex-A710 erratum 2054223
903
904	  Affected cores may fail to flush the trace data on a TSB instruction, when
905	  the PE is in trace prohibited state. This will cause losing a few bytes
906	  of the trace cached.
907
908	  Workaround is to issue two TSB consecutively on affected cores.
909
910	  If unsure, say Y.
911
912config ARM64_ERRATUM_2067961
913	bool "Neoverse-N2: 2067961: workaround TSB instruction failing to flush trace"
914	default y
915	select ARM64_WORKAROUND_TSB_FLUSH_FAILURE
916	help
917	  Enable workaround for ARM Neoverse-N2 erratum 2067961
918
919	  Affected cores may fail to flush the trace data on a TSB instruction, when
920	  the PE is in trace prohibited state. This will cause losing a few bytes
921	  of the trace cached.
922
923	  Workaround is to issue two TSB consecutively on affected cores.
924
925	  If unsure, say Y.
926
927config ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE
928	bool
929
930config ARM64_ERRATUM_2253138
931	bool "Neoverse-N2: 2253138: workaround TRBE writing to address out-of-range"
932	depends on CORESIGHT_TRBE
933	default y
934	select ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE
935	help
936	  This option adds the workaround for ARM Neoverse-N2 erratum 2253138.
937
938	  Affected Neoverse-N2 cores might write to an out-of-range address, not reserved
939	  for TRBE. Under some conditions, the TRBE might generate a write to the next
940	  virtually addressed page following the last page of the TRBE address space
941	  (i.e., the TRBLIMITR_EL1.LIMIT), instead of wrapping around to the base.
942
943	  Work around this in the driver by always making sure that there is a
944	  page beyond the TRBLIMITR_EL1.LIMIT, within the space allowed for the TRBE.
945
946	  If unsure, say Y.
947
948config ARM64_ERRATUM_2224489
949	bool "Cortex-A710/X2: 2224489: workaround TRBE writing to address out-of-range"
950	depends on CORESIGHT_TRBE
951	default y
952	select ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE
953	help
954	  This option adds the workaround for ARM Cortex-A710/X2 erratum 2224489.
955
956	  Affected Cortex-A710/X2 cores might write to an out-of-range address, not reserved
957	  for TRBE. Under some conditions, the TRBE might generate a write to the next
958	  virtually addressed page following the last page of the TRBE address space
959	  (i.e., the TRBLIMITR_EL1.LIMIT), instead of wrapping around to the base.
960
961	  Work around this in the driver by always making sure that there is a
962	  page beyond the TRBLIMITR_EL1.LIMIT, within the space allowed for the TRBE.
963
964	  If unsure, say Y.
965
966config ARM64_ERRATUM_2441009
967	bool "Cortex-A510: Completion of affected memory accesses might not be guaranteed by completion of a TLBI (rare)"
968	select ARM64_WORKAROUND_REPEAT_TLBI_SYNC
969	help
970	  This option adds a workaround for ARM Cortex-A510 erratum #2441009.
971
972	  Under very rare circumstances, affected Cortex-A510 CPUs
973	  may not handle a race between a break-before-make sequence on one
974	  CPU, and another CPU accessing the same page. This could allow a
975	  store to a page that has been unmapped.
976
977	  Work around this by adding the affected CPUs to the list that needs
978	  TLB sequences to be done twice.
979
980	  If unsure, say N.
981
982config ARM64_ERRATUM_2064142
983	bool "Cortex-A510: 2064142: workaround TRBE register writes while disabled"
984	depends on CORESIGHT_TRBE
985	default y
986	help
987	  This option adds the workaround for ARM Cortex-A510 erratum 2064142.
988
989	  Affected Cortex-A510 core might fail to write into system registers after the
990	  TRBE has been disabled. Under some conditions after the TRBE has been disabled
991	  writes into TRBE registers TRBLIMITR_EL1, TRBPTR_EL1, TRBBASER_EL1, TRBSR_EL1,
992	  and TRBTRG_EL1 will be ignored and will not be effected.
993
994	  Work around this in the driver by executing TSB CSYNC and DSB after collection
995	  is stopped and before performing a system register write to one of the affected
996	  registers.
997
998	  If unsure, say Y.
999
1000config ARM64_ERRATUM_2038923
1001	bool "Cortex-A510: 2038923: workaround TRBE corruption with enable"
1002	depends on CORESIGHT_TRBE
1003	default y
1004	help
1005	  This option adds the workaround for ARM Cortex-A510 erratum 2038923.
1006
1007	  Affected Cortex-A510 core might cause an inconsistent view on whether trace is
1008	  prohibited within the CPU. As a result, the trace buffer or trace buffer state
1009	  might be corrupted. This happens after TRBE buffer has been enabled by setting
1010	  TRBLIMITR_EL1.E, followed by just a single context synchronization event before
1011	  execution changes from a context, in which trace is prohibited to one where it
1012	  isn't, or vice versa. In these mentioned conditions, the view of whether trace
1013	  is prohibited is inconsistent between parts of the CPU, and the trace buffer or
1014	  the trace buffer state might be corrupted.
1015
1016	  Work around this in the driver by preventing an inconsistent view of whether the
1017	  trace is prohibited or not based on TRBLIMITR_EL1.E by immediately following a
1018	  change to TRBLIMITR_EL1.E with at least one ISB instruction before an ERET, or
1019	  two ISB instructions if no ERET is to take place.
1020
1021	  If unsure, say Y.
1022
1023config ARM64_ERRATUM_1902691
1024	bool "Cortex-A510: 1902691: workaround TRBE trace corruption"
1025	depends on CORESIGHT_TRBE
1026	default y
1027	help
1028	  This option adds the workaround for ARM Cortex-A510 erratum 1902691.
1029
1030	  Affected Cortex-A510 core might cause trace data corruption, when being written
1031	  into the memory. Effectively TRBE is broken and hence cannot be used to capture
1032	  trace data.
1033
1034	  Work around this problem in the driver by just preventing TRBE initialization on
1035	  affected cpus. The firmware must have disabled the access to TRBE for the kernel
1036	  on such implementations. This will cover the kernel for any firmware that doesn't
1037	  do this already.
1038
1039	  If unsure, say Y.
1040
1041config ARM64_ERRATUM_2457168
1042	bool "Cortex-A510: 2457168: workaround for AMEVCNTR01 incrementing incorrectly"
1043	depends on ARM64_AMU_EXTN
1044	default y
1045	help
1046	  This option adds the workaround for ARM Cortex-A510 erratum 2457168.
1047
1048	  The AMU counter AMEVCNTR01 (constant counter) should increment at the same rate
1049	  as the system counter. On affected Cortex-A510 cores AMEVCNTR01 increments
1050	  incorrectly giving a significantly higher output value.
1051
1052	  Work around this problem by returning 0 when reading the affected counter in
1053	  key locations that results in disabling all users of this counter. This effect
1054	  is the same to firmware disabling affected counters.
1055
1056	  If unsure, say Y.
1057
1058config ARM64_ERRATUM_2645198
1059	bool "Cortex-A715: 2645198: Workaround possible [ESR|FAR]_ELx corruption"
1060	default y
1061	help
1062	  This option adds the workaround for ARM Cortex-A715 erratum 2645198.
1063
1064	  If a Cortex-A715 cpu sees a page mapping permissions change from executable
1065	  to non-executable, it may corrupt the ESR_ELx and FAR_ELx registers on the
1066	  next instruction abort caused by permission fault.
1067
1068	  Only user-space does executable to non-executable permission transition via
1069	  mprotect() system call. Workaround the problem by doing a break-before-make
1070	  TLB invalidation, for all changes to executable user space mappings.
1071
1072	  If unsure, say Y.
1073
1074config ARM64_WORKAROUND_SPECULATIVE_UNPRIV_LOAD
1075	bool
1076
1077config ARM64_ERRATUM_2966298
1078	bool "Cortex-A520: 2966298: workaround for speculatively executed unprivileged load"
1079	select ARM64_WORKAROUND_SPECULATIVE_UNPRIV_LOAD
1080	default y
1081	help
1082	  This option adds the workaround for ARM Cortex-A520 erratum 2966298.
1083
1084	  On an affected Cortex-A520 core, a speculatively executed unprivileged
1085	  load might leak data from a privileged level via a cache side channel.
1086
1087	  Work around this problem by executing a TLBI before returning to EL0.
1088
1089	  If unsure, say Y.
1090
1091config ARM64_ERRATUM_3117295
1092	bool "Cortex-A510: 3117295: workaround for speculatively executed unprivileged load"
1093	select ARM64_WORKAROUND_SPECULATIVE_UNPRIV_LOAD
1094	default y
1095	help
1096	  This option adds the workaround for ARM Cortex-A510 erratum 3117295.
1097
1098	  On an affected Cortex-A510 core, a speculatively executed unprivileged
1099	  load might leak data from a privileged level via a cache side channel.
1100
1101	  Work around this problem by executing a TLBI before returning to EL0.
1102
1103	  If unsure, say Y.
1104
1105config ARM64_ERRATUM_3194386
1106	bool "Cortex-*/Neoverse-*: workaround for MSR SSBS not self-synchronizing"
1107	default y
1108	help
1109	  This option adds the workaround for the following errata:
1110
1111	  * ARM Cortex-A76 erratum 3324349
1112	  * ARM Cortex-A77 erratum 3324348
1113	  * ARM Cortex-A78 erratum 3324344
1114	  * ARM Cortex-A78C erratum 3324346
1115	  * ARM Cortex-A78C erratum 3324347
1116	  * ARM Cortex-A710 erratam 3324338
1117	  * ARM Cortex-A715 errartum 3456084
1118	  * ARM Cortex-A720 erratum 3456091
1119	  * ARM Cortex-A725 erratum 3456106
1120	  * ARM Cortex-X1 erratum 3324344
1121	  * ARM Cortex-X1C erratum 3324346
1122	  * ARM Cortex-X2 erratum 3324338
1123	  * ARM Cortex-X3 erratum 3324335
1124	  * ARM Cortex-X4 erratum 3194386
1125	  * ARM Cortex-X925 erratum 3324334
1126	  * ARM Neoverse-N1 erratum 3324349
1127	  * ARM Neoverse N2 erratum 3324339
1128	  * ARM Neoverse-N3 erratum 3456111
1129	  * ARM Neoverse-V1 erratum 3324341
1130	  * ARM Neoverse V2 erratum 3324336
1131	  * ARM Neoverse-V3 erratum 3312417
1132	  * ARM Neoverse-V3AE erratum 3312417
1133
1134	  On affected cores "MSR SSBS, #0" instructions may not affect
1135	  subsequent speculative instructions, which may permit unexepected
1136	  speculative store bypassing.
1137
1138	  Work around this problem by placing a Speculation Barrier (SB) or
1139	  Instruction Synchronization Barrier (ISB) after kernel changes to
1140	  SSBS. The presence of the SSBS special-purpose register is hidden
1141	  from hwcaps and EL0 reads of ID_AA64PFR1_EL1, such that userspace
1142	  will use the PR_SPEC_STORE_BYPASS prctl to change SSBS.
1143
1144	  If unsure, say Y.
1145
1146config ARM64_ERRATUM_4311569
1147	bool "SI L1: 4311569: workaround for premature CMO completion erratum"
1148	default y
1149	help
1150	  This option adds the workaround for ARM SI L1 erratum 4311569.
1151
1152	  The erratum of SI L1 can cause an early response to a combined write
1153	  and cache maintenance operation (WR+CMO) before the operation is fully
1154	  completed to the Point of Serialization (POS).
1155	  This can result in a non-I/O coherent agent observing stale data,
1156	  potentially leading to system instability or incorrect behavior.
1157
1158	  Enabling this option implements a software workaround by inserting a
1159	  second loop of Cache Maintenance Operation (CMO) immediately following the
1160	  end of function to do CMOs. This ensures that the data is correctly serialized
1161	  before the buffer is handed off to a non-coherent agent.
1162
1163	  If unsure, say Y.
1164
1165config ARM64_ERRATUM_4193714
1166	bool "C1-Pro: 4193714: SME DVMSync early acknowledgement"
1167	depends on ARM64_SME
1168	default y
1169	help
1170	  Enable workaround for C1-Pro acknowledging the DVMSync before
1171	  the SME memory accesses are complete. This will cause TLB
1172	  maintenance for processes using SME to also issue an IPI to
1173	  the affected CPUs.
1174
1175	  If unsure, say Y.
1176
1177config ARM64_ERRATUM_4118414
1178	bool "Various: Completion of affected memory accesses might not be guaranteed by completion of a TLBI"
1179	default y
1180	select ARM64_WORKAROUND_REPEAT_TLBI_SYNC
1181	help
1182	  This option adds a workaround for the following errata:
1183
1184	  * ARM C1-Premium erratum 4193780
1185	  * ARM C1-Ultra erratum 4193780
1186	  * ARM Cortex-A76 erratum 4193800
1187	  * ARM Cortex-A76AE erratum 4193801
1188	  * ARM Cortex-A77 erratum 4193798
1189	  * ARM Cortex-A78 erratum 4193791
1190	  * ARM Cortex-A78AE erratum 4193793
1191	  * ARM Cortex-A78C erratum 4193794
1192	  * ARM Cortex-A710 erratum 4193788
1193	  * ARM Cortex-X1 erratum 4193791
1194	  * ARM Cortex-X1C erratum 4193792
1195	  * ARM Cortex-X2 erratum 4193788
1196	  * ARM Cortex-X3 erratum 4193786
1197	  * ARM Cortex-X4 erratum 4118414
1198	  * ARM Cortex-X925 erratum 4193781
1199	  * ARM Neoverse-N1 erratum 4193800
1200	  * ARM Neoverse-N2 erratum 4193789
1201	  * ARM Neoverse-V1 erratum 4193790
1202	  * ARM Neoverse-V2 erratum 4193787
1203	  * ARM Neoverse-V3 erratum 4193784
1204	  * ARM Neoverse-V3AE erratum 4193784
1205	  * Microsoft Azure Cobalt 100 4193789
1206	  * NVIDIA Olympus erratum T410-OLY-1029
1207
1208	  On affected cores, some memory accesses might not be completed by
1209	  broadcast TLB invalidation.
1210
1211	  This issue is also known as CVE-2025-10263.
1212
1213	  If unsure, say Y.
1214
1215config CAVIUM_ERRATUM_22375
1216	bool "Cavium erratum 22375, 24313"
1217	default y
1218	help
1219	  Enable workaround for errata 22375 and 24313.
1220
1221	  This implements two gicv3-its errata workarounds for ThunderX. Both
1222	  with a small impact affecting only ITS table allocation.
1223
1224	    erratum 22375: only alloc 8MB table size
1225	    erratum 24313: ignore memory access type
1226
1227	  The fixes are in ITS initialization and basically ignore memory access
1228	  type and table size provided by the TYPER and BASER registers.
1229
1230	  If unsure, say Y.
1231
1232config CAVIUM_ERRATUM_23144
1233	bool "Cavium erratum 23144: ITS SYNC hang on dual socket system"
1234	depends on NUMA
1235	default y
1236	help
1237	  ITS SYNC command hang for cross node io and collections/cpu mapping.
1238
1239	  If unsure, say Y.
1240
1241config CAVIUM_ERRATUM_23154
1242	bool "Cavium errata 23154 and 38545: GICv3 lacks HW synchronisation"
1243	default y
1244	help
1245	  The ThunderX GICv3 implementation requires a modified version for
1246	  reading the IAR status to ensure data synchronization
1247	  (access to icc_iar1_el1 is not sync'ed before and after).
1248
1249	  It also suffers from erratum 38545 (also present on Marvell's
1250	  OcteonTX and OcteonTX2), resulting in deactivated interrupts being
1251	  spuriously presented to the CPU interface.
1252
1253	  If unsure, say Y.
1254
1255config CAVIUM_ERRATUM_27456
1256	bool "Cavium erratum 27456: Broadcast TLBI instructions may cause icache corruption"
1257	default y
1258	help
1259	  On ThunderX T88 pass 1.x through 2.1 parts, broadcast TLBI
1260	  instructions may cause the icache to become corrupted if it
1261	  contains data for a non-current ASID.  The fix is to
1262	  invalidate the icache when changing the mm context.
1263
1264	  If unsure, say Y.
1265
1266config CAVIUM_ERRATUM_30115
1267	bool "Cavium erratum 30115: Guest may disable interrupts in host"
1268	default y
1269	help
1270	  On ThunderX T88 pass 1.x through 2.2, T81 pass 1.0 through
1271	  1.2, and T83 Pass 1.0, KVM guest execution may disable
1272	  interrupts in host. Trapping both GICv3 group-0 and group-1
1273	  accesses sidesteps the issue.
1274
1275	  If unsure, say Y.
1276
1277config CAVIUM_TX2_ERRATUM_219
1278	bool "Cavium ThunderX2 erratum 219: PRFM between TTBR change and ISB fails"
1279	default y
1280	help
1281	  On Cavium ThunderX2, a load, store or prefetch instruction between a
1282	  TTBR update and the corresponding context synchronizing operation can
1283	  cause a spurious Data Abort to be delivered to any hardware thread in
1284	  the CPU core.
1285
1286	  Work around the issue by avoiding the problematic code sequence and
1287	  trapping KVM guest TTBRx_EL1 writes to EL2 when SMT is enabled. The
1288	  trap handler performs the corresponding register access, skips the
1289	  instruction and ensures context synchronization by virtue of the
1290	  exception return.
1291
1292	  If unsure, say Y.
1293
1294config FUJITSU_ERRATUM_010001
1295	bool "Fujitsu-A64FX erratum E#010001: Undefined fault may occur wrongly"
1296	default y
1297	help
1298	  This option adds a workaround for Fujitsu-A64FX erratum E#010001.
1299	  On some variants of the Fujitsu-A64FX cores ver(1.0, 1.1), memory
1300	  accesses may cause undefined fault (Data abort, DFSC=0b111111).
1301	  This fault occurs under a specific hardware condition when a
1302	  load/store instruction performs an address translation using:
1303	  case-1  TTBR0_EL1 with TCR_EL1.NFD0 == 1.
1304	  case-2  TTBR0_EL2 with TCR_EL2.NFD0 == 1.
1305	  case-3  TTBR1_EL1 with TCR_EL1.NFD1 == 1.
1306	  case-4  TTBR1_EL2 with TCR_EL2.NFD1 == 1.
1307
1308	  The workaround is to ensure these bits are clear in TCR_ELx.
1309	  The workaround only affects the Fujitsu-A64FX.
1310
1311	  If unsure, say Y.
1312
1313config HISILICON_ERRATUM_161600802
1314	bool "Hip07 161600802: Erroneous redistributor VLPI base"
1315	default y
1316	help
1317	  The HiSilicon Hip07 SoC uses the wrong redistributor base
1318	  when issued ITS commands such as VMOVP and VMAPP, and requires
1319	  a 128kB offset to be applied to the target address in this commands.
1320
1321	  If unsure, say Y.
1322
1323config HISILICON_ERRATUM_162100801
1324	bool "Hip09 162100801 erratum support"
1325	default y
1326	help
1327	  When enabling GICv4.1 in hip09, VMAPP will fail to clear some caches
1328	  during unmapping operation, which will cause some vSGIs lost.
1329	  To fix the issue, invalidate related vPE cache through GICR_INVALLR
1330	  after VMOVP.
1331
1332	  If unsure, say Y.
1333
1334config HISILICON_ERRATUM_162100125
1335	bool "Hisilicon erratum 162100125"
1336	default y
1337	select ARM64_WORKAROUND_DISABLE_CNP
1338	help
1339	  On HiSilicon HIP09, TLB entry matching behavior when CNP
1340	  (TTBRx.CNP=1) is enabled differs from the ARM architecture
1341	  specification.
1342
1343	  TLB entries may be incorrectly shared between CPUs, potentially
1344	  causing TLB conflicts and stale mappings.
1345
1346	  Disable CNP support for affected HiSilicon HIP09 cores.
1347
1348	  If unsure, say Y.
1349
1350config QCOM_FALKOR_ERRATUM_1003
1351	bool "Falkor E1003: Incorrect translation due to ASID change"
1352	default y
1353	help
1354	  On Falkor v1, an incorrect ASID may be cached in the TLB when ASID
1355	  and BADDR are changed together in TTBRx_EL1. Since we keep the ASID
1356	  in TTBR1_EL1, this situation only occurs in the entry trampoline and
1357	  then only for entries in the walk cache, since the leaf translation
1358	  is unchanged. Work around the erratum by invalidating the walk cache
1359	  entries for the trampoline before entering the kernel proper.
1360
1361config QCOM_FALKOR_ERRATUM_1009
1362	bool "Falkor E1009: Prematurely complete a DSB after a TLBI"
1363	default y
1364	select ARM64_WORKAROUND_REPEAT_TLBI_SYNC
1365	help
1366	  On Falkor v1, the CPU may prematurely complete a DSB following a
1367	  TLBI xxIS invalidate maintenance operation. Repeat the TLBI operation
1368	  one more time to fix the issue.
1369
1370	  If unsure, say Y.
1371
1372config QCOM_QDF2400_ERRATUM_0065
1373	bool "QDF2400 E0065: Incorrect GITS_TYPER.ITT_Entry_size"
1374	default y
1375	help
1376	  On Qualcomm Datacenter Technologies QDF2400 SoC, ITS hardware reports
1377	  ITE size incorrectly. The GITS_TYPER.ITT_Entry_size field should have
1378	  been indicated as 16Bytes (0xf), not 8Bytes (0x7).
1379
1380	  If unsure, say Y.
1381
1382config QCOM_FALKOR_ERRATUM_E1041
1383	bool "Falkor E1041: Speculative instruction fetches might cause errant memory access"
1384	default y
1385	help
1386	  Falkor CPU may speculatively fetch instructions from an improper
1387	  memory location when MMU translation is changed from SCTLR_ELn[M]=1
1388	  to SCTLR_ELn[M]=0. Prefix an ISB instruction to fix the problem.
1389
1390	  If unsure, say Y.
1391
1392config ARM64_WORKAROUND_DISABLE_CNP
1393	bool
1394
1395config NVIDIA_CARMEL_CNP_ERRATUM
1396	bool "NVIDIA Carmel CNP: CNP on Carmel semantically different than ARM cores"
1397	default y
1398	select ARM64_WORKAROUND_DISABLE_CNP
1399	help
1400	  If CNP is enabled on Carmel cores, non-sharable TLBIs on a core will not
1401	  invalidate shared TLB entries installed by a different core, as it would
1402	  on standard ARM cores.
1403
1404	  If unsure, say Y.
1405
1406config NVIDIA_OLYMPUS_1027_ERRATUM
1407	bool "NVIDIA Olympus: device store/load ordering erratum"
1408	default y
1409	help
1410	  This option adds an alternative code sequence to work around an
1411	  NVIDIA Olympus core erratum where a Device-nGnR* store can be
1412	  observed by a peripheral after a younger Device-nGnR* load to the
1413	  same peripheral. This breaks the program order that drivers rely
1414	  on for MMIO and can leave a device in an incorrect state.
1415
1416	  The workaround inserts a DMB OSH immediately before raw MMIO loads.
1417	  The erratum cannot occur when a DMB that orders loads appears
1418	  between the store and load, preventing the younger load from being
1419	  observed before the older store.
1420
1421	  The alternatives framework patches in DMB OSH only when an affected
1422	  CPU is detected. Other CPUs execute a NOP in its place. Disabling
1423	  this option leaves the original MMIO read instruction stream
1424	  unchanged.
1425
1426	  If unsure, say Y.
1427
1428config RENESAS_ERRATUM_GEN4GICITS1
1429	bool "Renesas R-Car Gen4: GIC600 can not access physical addresses above 4 GiB"
1430	default y
1431	help
1432	  The Renesas R-Car Gen4 S4/V4H/V4M GIC600 SoC integrations have AXI
1433	  addressing limited to the first 32-bit of physical address space.
1434
1435	  If unsure, say Y.
1436
1437config ROCKCHIP_ERRATUM_3568002
1438	bool "Rockchip 3568002: GIC600 can not access physical addresses higher than 4GB"
1439	default y
1440	help
1441	  The Rockchip RK3566 and RK3568 GIC600 SoC integrations have AXI
1442	  addressing limited to the first 32bit of physical address space.
1443
1444	  If unsure, say Y.
1445
1446config ROCKCHIP_ERRATUM_3588001
1447	bool "Rockchip 3588001: GIC600 can not support shareability attributes"
1448	default y
1449	help
1450	  The Rockchip RK3588 GIC600 SoC integration does not support ACE/ACE-lite.
1451	  This means, that its sharability feature may not be used, even though it
1452	  is supported by the IP itself.
1453
1454	  If unsure, say Y.
1455
1456config SOCIONEXT_SYNQUACER_PREITS
1457	bool "Socionext Synquacer: Workaround for GICv3 pre-ITS"
1458	default y
1459	help
1460	  Socionext Synquacer SoCs implement a separate h/w block to generate
1461	  MSI doorbell writes with non-zero values for the device ID.
1462
1463	  If unsure, say Y.
1464
1465endmenu # "ARM errata workarounds via the alternatives framework"
1466
1467choice
1468	prompt "Page size"
1469	default ARM64_4K_PAGES
1470	help
1471	  Page size (translation granule) configuration.
1472
1473config ARM64_4K_PAGES
1474	bool "4KB"
1475	select HAVE_PAGE_SIZE_4KB
1476	help
1477	  This feature enables 4KB pages support.
1478
1479config ARM64_16K_PAGES
1480	bool "16KB"
1481	select HAVE_PAGE_SIZE_16KB
1482	help
1483	  The system will use 16KB pages support. AArch32 emulation
1484	  requires applications compiled with 16K (or a multiple of 16K)
1485	  aligned segments.
1486
1487config ARM64_64K_PAGES
1488	bool "64KB"
1489	select HAVE_PAGE_SIZE_64KB
1490	help
1491	  This feature enables 64KB pages support (4KB by default)
1492	  allowing only two levels of page tables and faster TLB
1493	  look-up. AArch32 emulation requires applications compiled
1494	  with 64K aligned segments.
1495
1496endchoice
1497
1498choice
1499	prompt "Virtual address space size"
1500	default ARM64_VA_BITS_52
1501	help
1502	  Allows choosing one of multiple possible virtual address
1503	  space sizes. The level of translation table is determined by
1504	  a combination of page size and virtual address space size.
1505
1506config ARM64_VA_BITS_36
1507	bool "36-bit" if EXPERT
1508	depends on PAGE_SIZE_16KB
1509
1510config ARM64_VA_BITS_39
1511	bool "39-bit"
1512	depends on PAGE_SIZE_4KB
1513
1514config ARM64_VA_BITS_42
1515	bool "42-bit"
1516	depends on PAGE_SIZE_64KB
1517
1518config ARM64_VA_BITS_47
1519	bool "47-bit"
1520	depends on PAGE_SIZE_16KB
1521
1522config ARM64_VA_BITS_48
1523	bool "48-bit"
1524
1525config ARM64_VA_BITS_52
1526	bool "52-bit"
1527	help
1528	  Enable 52-bit virtual addressing for userspace when explicitly
1529	  requested via a hint to mmap(). The kernel will also use 52-bit
1530	  virtual addresses for its own mappings (provided HW support for
1531	  this feature is available, otherwise it reverts to 48-bit).
1532
1533	  NOTE: Enabling 52-bit virtual addressing in conjunction with
1534	  ARMv8.3 Pointer Authentication will result in the PAC being
1535	  reduced from 7 bits to 3 bits, which may have a significant
1536	  impact on its susceptibility to brute-force attacks.
1537
1538	  If unsure, select 48-bit virtual addressing instead.
1539
1540endchoice
1541
1542config ARM64_FORCE_52BIT
1543	bool "Force 52-bit virtual addresses for userspace"
1544	depends on ARM64_VA_BITS_52 && EXPERT
1545	help
1546	  For systems with 52-bit userspace VAs enabled, the kernel will attempt
1547	  to maintain compatibility with older software by providing 48-bit VAs
1548	  unless a hint is supplied to mmap.
1549
1550	  This configuration option disables the 48-bit compatibility logic, and
1551	  forces all userspace addresses to be 52-bit on HW that supports it. One
1552	  should only enable this configuration option for stress testing userspace
1553	  memory management code. If unsure say N here.
1554
1555config ARM64_VA_BITS
1556	int
1557	default 36 if ARM64_VA_BITS_36
1558	default 39 if ARM64_VA_BITS_39
1559	default 42 if ARM64_VA_BITS_42
1560	default 47 if ARM64_VA_BITS_47
1561	default 48 if ARM64_VA_BITS_48
1562	default 52 if ARM64_VA_BITS_52
1563
1564choice
1565	prompt "Physical address space size"
1566	default ARM64_PA_BITS_48
1567	help
1568	  Choose the maximum physical address range that the kernel will
1569	  support.
1570
1571config ARM64_PA_BITS_48
1572	bool "48-bit"
1573	depends on ARM64_64K_PAGES || !ARM64_VA_BITS_52
1574
1575config ARM64_PA_BITS_52
1576	bool "52-bit"
1577	depends on ARM64_64K_PAGES || ARM64_VA_BITS_52
1578	help
1579	  Enable support for a 52-bit physical address space, introduced as
1580	  part of the ARMv8.2-LPA extension.
1581
1582	  With this enabled, the kernel will also continue to work on CPUs that
1583	  do not support ARMv8.2-LPA, but with some added memory overhead (and
1584	  minor performance overhead).
1585
1586endchoice
1587
1588config ARM64_PA_BITS
1589	int
1590	default 48 if ARM64_PA_BITS_48
1591	default 52 if ARM64_PA_BITS_52
1592
1593config ARM64_LPA2
1594	def_bool y
1595	depends on ARM64_PA_BITS_52 && !ARM64_64K_PAGES
1596
1597choice
1598	prompt "Endianness"
1599	default CPU_LITTLE_ENDIAN
1600	help
1601	  Select the endianness of data accesses performed by the CPU. Userspace
1602	  applications will need to be compiled and linked for the endianness
1603	  that is selected here.
1604
1605config CPU_BIG_ENDIAN
1606	bool "Build big-endian kernel"
1607	depends on BROKEN
1608	help
1609	  Say Y if you plan on running a kernel with a big-endian userspace.
1610
1611config CPU_LITTLE_ENDIAN
1612	bool "Build little-endian kernel"
1613	help
1614	  Say Y if you plan on running a kernel with a little-endian userspace.
1615	  This is usually the case for distributions targeting arm64.
1616
1617endchoice
1618
1619config NR_CPUS
1620	int "Maximum number of CPUs (2-4096)"
1621	range 2 4096
1622	default "512"
1623
1624config HOTPLUG_CPU
1625	bool "Support for hot-pluggable CPUs"
1626	select GENERIC_IRQ_MIGRATION
1627	help
1628	  Say Y here to experiment with turning CPUs off and on.  CPUs
1629	  can be controlled through /sys/devices/system/cpu.
1630
1631# Common NUMA Features
1632config NUMA
1633	bool "NUMA Memory Allocation and Scheduler Support"
1634	select GENERIC_ARCH_NUMA
1635	select OF_NUMA
1636	select HAVE_SETUP_PER_CPU_AREA
1637	select NEED_PER_CPU_EMBED_FIRST_CHUNK
1638	select NEED_PER_CPU_PAGE_FIRST_CHUNK
1639	select USE_PERCPU_NUMA_NODE_ID
1640	help
1641	  Enable NUMA (Non-Uniform Memory Access) support.
1642
1643	  The kernel will try to allocate memory used by a CPU on the
1644	  local memory of the CPU and add some more
1645	  NUMA awareness to the kernel.
1646
1647config NODES_SHIFT
1648	int "Maximum NUMA Nodes (as a power of 2)"
1649	range 1 10
1650	default "4"
1651	depends on NUMA
1652	help
1653	  Specify the maximum number of NUMA Nodes available on the target
1654	  system.  Increases memory reserved to accommodate various tables.
1655
1656source "kernel/Kconfig.hz"
1657
1658config ARCH_SPARSEMEM_ENABLE
1659	def_bool y
1660	select SPARSEMEM_VMEMMAP_ENABLE
1661
1662config HW_PERF_EVENTS
1663	def_bool y
1664	depends on ARM_PMU
1665
1666# Supported by clang >= 7.0 or GCC >= 12.0.0
1667config CC_HAVE_SHADOW_CALL_STACK
1668	def_bool $(cc-option, -fsanitize=shadow-call-stack -ffixed-x18)
1669
1670config PARAVIRT
1671	bool "Enable paravirtualization code"
1672	select HAVE_PV_STEAL_CLOCK_GEN
1673	help
1674	  This changes the kernel so it can modify itself when it is run
1675	  under a hypervisor, potentially improving performance significantly
1676	  over full virtualization.
1677
1678config PARAVIRT_TIME_ACCOUNTING
1679	bool "Paravirtual steal time accounting"
1680	select PARAVIRT
1681	help
1682	  Select this option to enable fine granularity task steal time
1683	  accounting. Time spent executing other tasks in parallel with
1684	  the current vCPU is discounted from the vCPU power. To account for
1685	  that, there can be a small performance impact.
1686
1687	  If in doubt, say N here.
1688
1689config ARCH_SUPPORTS_KEXEC
1690	def_bool PM_SLEEP_SMP
1691
1692config ARCH_SUPPORTS_KEXEC_FILE
1693	def_bool y
1694
1695config ARCH_SELECTS_KEXEC_FILE
1696	def_bool y
1697	depends on KEXEC_FILE
1698	select HAVE_IMA_KEXEC if IMA
1699
1700config ARCH_SUPPORTS_KEXEC_SIG
1701	def_bool y
1702
1703config ARCH_SUPPORTS_KEXEC_IMAGE_VERIFY_SIG
1704	def_bool y
1705
1706config ARCH_DEFAULT_KEXEC_IMAGE_VERIFY_SIG
1707	def_bool y
1708
1709config ARCH_SUPPORTS_KEXEC_HANDOVER
1710	def_bool y
1711
1712config ARCH_SUPPORTS_CRASH_DUMP
1713	def_bool y
1714
1715config ARCH_DEFAULT_CRASH_DUMP
1716	def_bool y
1717
1718config ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION
1719	def_bool CRASH_RESERVE
1720
1721config TRANS_TABLE
1722	def_bool y
1723	depends on HIBERNATION || KEXEC_CORE
1724
1725config XEN_DOM0
1726	def_bool y
1727	depends on XEN
1728
1729config XEN
1730	bool "Xen guest support on ARM64"
1731	depends on ARM64 && OF
1732	select SWIOTLB_XEN
1733	select PARAVIRT
1734	help
1735	  Say Y if you want to run Linux in a Virtual Machine on Xen on ARM64.
1736
1737# include/linux/mmzone.h requires the following to be true:
1738#
1739#   MAX_PAGE_ORDER + PAGE_SHIFT <= SECTION_SIZE_BITS
1740#
1741# so the maximum value of MAX_PAGE_ORDER is SECTION_SIZE_BITS - PAGE_SHIFT:
1742#
1743#     | SECTION_SIZE_BITS |  PAGE_SHIFT  |  max MAX_PAGE_ORDER  |  default MAX_PAGE_ORDER |
1744# ----+-------------------+--------------+----------------------+-------------------------+
1745# 4K  |       27          |      12      |       15             |         10              |
1746# 16K |       27          |      14      |       13             |         11              |
1747# 64K |       29          |      16      |       13             |         13              |
1748config ARCH_FORCE_MAX_ORDER
1749	int
1750	default "13" if ARM64_64K_PAGES
1751	default "11" if ARM64_16K_PAGES
1752	default "10"
1753	help
1754	  The kernel page allocator limits the size of maximal physically
1755	  contiguous allocations. The limit is called MAX_PAGE_ORDER and it
1756	  defines the maximal power of two of number of pages that can be
1757	  allocated as a single contiguous block. This option allows
1758	  overriding the default setting when ability to allocate very
1759	  large blocks of physically contiguous memory is required.
1760
1761	  The maximal size of allocation cannot exceed the size of the
1762	  section, so the value of MAX_PAGE_ORDER should satisfy
1763
1764	    MAX_PAGE_ORDER + PAGE_SHIFT <= SECTION_SIZE_BITS
1765
1766	  Don't change if unsure.
1767
1768config UNMAP_KERNEL_AT_EL0
1769	bool "Unmap kernel when running in userspace (KPTI)" if EXPERT
1770	default y
1771	help
1772	  Speculation attacks against some high-performance processors can
1773	  be used to bypass MMU permission checks and leak kernel data to
1774	  userspace. This can be defended against by unmapping the kernel
1775	  when running in userspace, mapping it back in on exception entry
1776	  via a trampoline page in the vector table.
1777
1778	  If unsure, say Y.
1779
1780config MITIGATE_SPECTRE_BRANCH_HISTORY
1781	bool "Mitigate Spectre style attacks against branch history" if EXPERT
1782	default y
1783	help
1784	  Speculation attacks against some high-performance processors can
1785	  make use of branch history to influence future speculation.
1786	  When taking an exception from user-space, a sequence of branches
1787	  or a firmware call overwrites the branch history.
1788
1789config ARM64_SW_TTBR0_PAN
1790	bool "Emulate Privileged Access Never using TTBR0_EL1 switching"
1791	depends on !KCSAN
1792	help
1793	  Enabling this option prevents the kernel from accessing
1794	  user-space memory directly by pointing TTBR0_EL1 to a reserved
1795	  zeroed area and reserved ASID. The user access routines
1796	  restore the valid TTBR0_EL1 temporarily.
1797
1798config ARM64_TAGGED_ADDR_ABI
1799	bool "Enable the tagged user addresses syscall ABI"
1800	default y
1801	help
1802	  When this option is enabled, user applications can opt in to a
1803	  relaxed ABI via prctl() allowing tagged addresses to be passed
1804	  to system calls as pointer arguments. For details, see
1805	  Documentation/arch/arm64/tagged-address-abi.rst.
1806
1807menuconfig COMPAT
1808	bool "Kernel support for 32-bit EL0"
1809	depends on ARM64_4K_PAGES || EXPERT
1810	select HAVE_UID16
1811	select OLD_SIGSUSPEND3
1812	select COMPAT_OLD_SIGACTION
1813	help
1814	  This option enables support for a 32-bit EL0 running under a 64-bit
1815	  kernel at EL1. AArch32-specific components such as system calls,
1816	  the user helper functions, VFP support and the ptrace interface are
1817	  handled appropriately by the kernel.
1818
1819	  If you use a page size other than 4KB (i.e, 16KB or 64KB), please be aware
1820	  that you will only be able to execute AArch32 binaries that were compiled
1821	  with page size aligned segments.
1822
1823	  If you want to execute 32-bit userspace applications, say Y.
1824
1825if COMPAT
1826
1827config KUSER_HELPERS
1828	bool "Enable kuser helpers page for 32-bit applications"
1829	default y
1830	help
1831	  Warning: disabling this option may break 32-bit user programs.
1832
1833	  Provide kuser helpers to compat tasks. The kernel provides
1834	  helper code to userspace in read only form at a fixed location
1835	  to allow userspace to be independent of the CPU type fitted to
1836	  the system. This permits binaries to be run on ARMv4 through
1837	  to ARMv8 without modification.
1838
1839	  See Documentation/arch/arm/kernel_user_helpers.rst for details.
1840
1841	  However, the fixed address nature of these helpers can be used
1842	  by ROP (return orientated programming) authors when creating
1843	  exploits.
1844
1845	  If all of the binaries and libraries which run on your platform
1846	  are built specifically for your platform, and make no use of
1847	  these helpers, then you can turn this option off to hinder
1848	  such exploits. However, in that case, if a binary or library
1849	  relying on those helpers is run, it will not function correctly.
1850
1851	  Say N here only if you are absolutely certain that you do not
1852	  need these helpers; otherwise, the safe option is to say Y.
1853
1854config COMPAT_VDSO
1855	bool "Enable vDSO for 32-bit applications"
1856	depends on !CPU_BIG_ENDIAN
1857	depends on (CC_IS_CLANG && LD_IS_LLD) || "$(CROSS_COMPILE_COMPAT)" != ""
1858	default y
1859	help
1860	  Place in the process address space of 32-bit applications an
1861	  ELF shared object providing fast implementations of gettimeofday
1862	  and clock_gettime.
1863
1864	  You must have a 32-bit build of glibc 2.22 or later for programs
1865	  to seamlessly take advantage of this.
1866
1867config THUMB2_COMPAT_VDSO
1868	bool "Compile the 32-bit vDSO for Thumb-2 mode" if EXPERT
1869	depends on COMPAT_VDSO
1870	default y
1871	help
1872	  Compile the compat vDSO with '-mthumb -fomit-frame-pointer' if y,
1873	  otherwise with '-marm'.
1874
1875config COMPAT_ALIGNMENT_FIXUPS
1876	bool "Fix up misaligned multi-word loads and stores in user space"
1877
1878menuconfig ARMV8_DEPRECATED
1879	bool "Emulate deprecated/obsolete ARMv8 instructions"
1880	depends on SYSCTL
1881	help
1882	  Legacy software support may require certain instructions
1883	  that have been deprecated or obsoleted in the architecture.
1884
1885	  Enable this config to enable selective emulation of these
1886	  features.
1887
1888	  If unsure, say Y
1889
1890if ARMV8_DEPRECATED
1891
1892config SWP_EMULATION
1893	bool "Emulate SWP/SWPB instructions"
1894	help
1895	  ARMv8 obsoletes the use of A32 SWP/SWPB instructions such that
1896	  they are always undefined. Say Y here to enable software
1897	  emulation of these instructions for userspace using LDXR/STXR.
1898	  This feature can be controlled at runtime with the abi.swp
1899	  sysctl which is disabled by default.
1900
1901	  In some older versions of glibc [<=2.8] SWP is used during futex
1902	  trylock() operations with the assumption that the code will not
1903	  be preempted. This invalid assumption may be more likely to fail
1904	  with SWP emulation enabled, leading to deadlock of the user
1905	  application.
1906
1907	  NOTE: when accessing uncached shared regions, LDXR/STXR rely
1908	  on an external transaction monitoring block called a global
1909	  monitor to maintain update atomicity. If your system does not
1910	  implement a global monitor, this option can cause programs that
1911	  perform SWP operations to uncached memory to deadlock.
1912
1913	  If unsure, say Y
1914
1915config CP15_BARRIER_EMULATION
1916	bool "Emulate CP15 Barrier instructions"
1917	help
1918	  The CP15 barrier instructions - CP15ISB, CP15DSB, and
1919	  CP15DMB - are deprecated in ARMv8 (and ARMv7). It is
1920	  strongly recommended to use the ISB, DSB, and DMB
1921	  instructions instead.
1922
1923	  Say Y here to enable software emulation of these
1924	  instructions for AArch32 userspace code. When this option is
1925	  enabled, CP15 barrier usage is traced which can help
1926	  identify software that needs updating. This feature can be
1927	  controlled at runtime with the abi.cp15_barrier sysctl.
1928
1929	  If unsure, say Y
1930
1931config SETEND_EMULATION
1932	bool "Emulate SETEND instruction"
1933	help
1934	  The SETEND instruction alters the data-endianness of the
1935	  AArch32 EL0, and is deprecated in ARMv8.
1936
1937	  Say Y here to enable software emulation of the instruction
1938	  for AArch32 userspace code. This feature can be controlled
1939	  at runtime with the abi.setend sysctl.
1940
1941	  Note: All the cpus on the system must have mixed endian support at EL0
1942	  for this feature to be enabled. If a new CPU - which doesn't support mixed
1943	  endian - is hotplugged in after this feature has been enabled, there could
1944	  be unexpected results in the applications.
1945
1946	  If unsure, say Y
1947endif # ARMV8_DEPRECATED
1948
1949endif # COMPAT
1950
1951menu "ARMv8.1 architectural features"
1952
1953config ARM64_HW_AFDBM
1954	bool "Support for hardware updates of the Access and Dirty page flags"
1955	default y
1956	help
1957	  The ARMv8.1 architecture extensions introduce support for
1958	  hardware updates of the access and dirty information in page
1959	  table entries. When enabled in TCR_EL1 (HA and HD bits) on
1960	  capable processors, accesses to pages with PTE_AF cleared will
1961	  set this bit instead of raising an access flag fault.
1962	  Similarly, writes to read-only pages with the DBM bit set will
1963	  clear the read-only bit (AP[2]) instead of raising a
1964	  permission fault.
1965
1966	  Kernels built with this configuration option enabled continue
1967	  to work on pre-ARMv8.1 hardware and the performance impact is
1968	  minimal. If unsure, say Y.
1969
1970endmenu # "ARMv8.1 architectural features"
1971
1972menu "ARMv8.2 architectural features"
1973
1974config ARM64_PMEM
1975	bool "Enable support for persistent memory"
1976	select ARCH_HAS_PMEM_API
1977	select ARCH_HAS_UACCESS_FLUSHCACHE
1978	help
1979	  Say Y to enable support for the persistent memory API based on the
1980	  ARMv8.2 DCPoP feature.
1981
1982	  The feature is detected at runtime, and the kernel will use DC CVAC
1983	  operations if DC CVAP is not supported (following the behaviour of
1984	  DC CVAP itself if the system does not define a point of persistence).
1985
1986config ARM64_RAS_EXTN
1987	bool "Enable support for RAS CPU Extensions"
1988	default y
1989	help
1990	  CPUs that support the Reliability, Availability and Serviceability
1991	  (RAS) Extensions, part of ARMv8.2 are able to track faults and
1992	  errors, classify them and report them to software.
1993
1994	  On CPUs with these extensions system software can use additional
1995	  barriers to determine if faults are pending and read the
1996	  classification from a new set of registers.
1997
1998	  Selecting this feature will allow the kernel to use these barriers
1999	  and access the new registers if the system supports the extension.
2000	  Platform RAS features may additionally depend on firmware support.
2001
2002config ARM64_CNP
2003	bool "Enable support for Common Not Private (CNP) translations"
2004	default y
2005	help
2006	  Common Not Private (CNP) allows translation table entries to
2007	  be shared between different PEs in the same inner shareable
2008	  domain, so the hardware can use this fact to optimise the
2009	  caching of such entries in the TLB.
2010
2011	  Selecting this option allows the CNP feature to be detected
2012	  at runtime, and does not affect PEs that do not implement
2013	  this feature.
2014
2015endmenu # "ARMv8.2 architectural features"
2016
2017menu "ARMv8.3 architectural features"
2018
2019config ARM64_PTR_AUTH
2020	bool "Enable support for pointer authentication"
2021	default y
2022	help
2023	  Pointer authentication (part of the ARMv8.3 Extensions) provides
2024	  instructions for signing and authenticating pointers against secret
2025	  keys, which can be used to mitigate Return Oriented Programming (ROP)
2026	  and other attacks.
2027
2028	  This option enables these instructions at EL0 (i.e. for userspace).
2029	  Choosing this option will cause the kernel to initialise secret keys
2030	  for each process at exec() time, with these keys being
2031	  context-switched along with the process.
2032
2033	  The feature is detected at runtime. If the feature is not present in
2034	  hardware it will not be advertised to userspace/KVM guest nor will it
2035	  be enabled.
2036
2037	  If the feature is present on the boot CPU but not on a late CPU, then
2038	  the late CPU will be parked. Also, if the boot CPU does not have
2039	  address auth and the late CPU has then the late CPU will still boot
2040	  but with the feature disabled. On such a system, this option should
2041	  not be selected.
2042
2043config ARM64_PTR_AUTH_KERNEL
2044	bool "Use pointer authentication for kernel"
2045	default y
2046	depends on ARM64_PTR_AUTH
2047	# Modern compilers insert a .note.gnu.property section note for PAC
2048	# which is only understood by binutils starting with version 2.33.1.
2049	depends on LD_IS_LLD || LD_VERSION >= 23301 || (CC_IS_GCC && GCC_VERSION < 90100)
2050	depends on !CC_IS_CLANG || AS_HAS_CFI_NEGATE_RA_STATE
2051	depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_ARGS)
2052	help
2053	  If the compiler supports the -mbranch-protection or
2054	  -msign-return-address flag (e.g. GCC 7 or later), then this option
2055	  will cause the kernel itself to be compiled with return address
2056	  protection. In this case, and if the target hardware is known to
2057	  support pointer authentication, then CONFIG_STACKPROTECTOR can be
2058	  disabled with minimal loss of protection.
2059
2060	  This feature works with FUNCTION_GRAPH_TRACER option only if
2061	  DYNAMIC_FTRACE_WITH_ARGS is enabled.
2062
2063config CC_HAS_BRANCH_PROT_PAC_RET
2064	# GCC 9 or later, clang 8 or later
2065	def_bool $(cc-option,-mbranch-protection=pac-ret+leaf)
2066
2067config AS_HAS_CFI_NEGATE_RA_STATE
2068	# binutils 2.34+
2069	def_bool $(as-instr,.cfi_startproc\n.cfi_negate_ra_state\n.cfi_endproc\n)
2070
2071endmenu # "ARMv8.3 architectural features"
2072
2073menu "ARMv8.4 architectural features"
2074
2075config ARM64_AMU_EXTN
2076	bool "Enable support for the Activity Monitors Unit CPU extension"
2077	default y
2078	help
2079	  The activity monitors extension is an optional extension introduced
2080	  by the ARMv8.4 CPU architecture. This enables support for version 1
2081	  of the activity monitors architecture, AMUv1.
2082
2083	  To enable the use of this extension on CPUs that implement it, say Y.
2084
2085	  Note that for architectural reasons, firmware _must_ implement AMU
2086	  support when running on CPUs that present the activity monitors
2087	  extension. The required support is present in:
2088	    * Version 1.5 and later of the ARM Trusted Firmware
2089
2090	  For kernels that have this configuration enabled but boot with broken
2091	  firmware, you may need to say N here until the firmware is fixed.
2092	  Otherwise you may experience firmware panics or lockups when
2093	  accessing the counter registers. Even if you are not observing these
2094	  symptoms, the values returned by the register reads might not
2095	  correctly reflect reality. Most commonly, the value read will be 0,
2096	  indicating that the counter is not enabled.
2097
2098config ARM64_TLB_RANGE
2099	bool "Enable support for tlbi range feature"
2100	default y
2101	help
2102	  ARMv8.4-TLBI provides TLBI invalidation instruction that apply to a
2103	  range of input addresses.
2104
2105config ARM64_MPAM
2106	bool "Enable support for MPAM"
2107	select ARM64_MPAM_DRIVER
2108	select ARCH_HAS_CPU_RESCTRL
2109	help
2110	  Memory System Resource Partitioning and Monitoring (MPAM) is an
2111	  optional extension to the Arm architecture that allows each
2112	  transaction issued to the memory system to be labelled with a
2113	  Partition identifier (PARTID) and Performance Monitoring Group
2114	  identifier (PMG).
2115
2116	  Memory system components, such as the caches, can be configured with
2117	  policies to control how much of various physical resources (such as
2118	  memory bandwidth or cache memory) the transactions labelled with each
2119	  PARTID can consume.  Depending on the capabilities of the hardware,
2120	  the PARTID and PMG can also be used as filtering criteria to measure
2121	  the memory system resource consumption of different parts of a
2122	  workload.
2123
2124	  Use of this extension requires CPU support, support in the
2125	  Memory System Components (MSC), and a description from firmware
2126	  of where the MSCs are in the address space.
2127
2128	  MPAM is exposed to user-space via the resctrl pseudo filesystem.
2129
2130	  This option enables the extra context switch code.
2131
2132endmenu # "ARMv8.4 architectural features"
2133
2134menu "ARMv8.5 architectural features"
2135
2136config AS_HAS_ARMV8_5
2137	def_bool $(cc-option,-Wa$(comma)-march=armv8.5-a)
2138
2139config ARM64_BTI
2140	bool "Branch Target Identification support"
2141	default y
2142	help
2143	  Branch Target Identification (part of the ARMv8.5 Extensions)
2144	  provides a mechanism to limit the set of locations to which computed
2145	  branch instructions such as BR or BLR can jump.
2146
2147	  To make use of BTI on CPUs that support it, say Y.
2148
2149	  BTI is intended to provide complementary protection to other control
2150	  flow integrity protection mechanisms, such as the Pointer
2151	  authentication mechanism provided as part of the ARMv8.3 Extensions.
2152	  For this reason, it does not make sense to enable this option without
2153	  also enabling support for pointer authentication.  Thus, when
2154	  enabling this option you should also select ARM64_PTR_AUTH=y.
2155
2156	  Userspace binaries must also be specifically compiled to make use of
2157	  this mechanism.  If you say N here or the hardware does not support
2158	  BTI, such binaries can still run, but you get no additional
2159	  enforcement of branch destinations.
2160
2161config ARM64_BTI_KERNEL
2162	bool "Use Branch Target Identification for kernel"
2163	default y
2164	depends on ARM64_BTI
2165	depends on ARM64_PTR_AUTH_KERNEL
2166	depends on CC_HAS_BRANCH_PROT_PAC_RET_BTI
2167	# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94697
2168	depends on !CC_IS_GCC || GCC_VERSION >= 100100
2169	# https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106671
2170	depends on !CC_IS_GCC
2171	# https://github.com/llvm/llvm-project/issues/215547
2172	depends on !CC_IS_CLANG || CLANG_VERSION < 210000
2173	depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_ARGS)
2174	help
2175	  Build the kernel with Branch Target Identification annotations
2176	  and enable enforcement of this for kernel code. When this option
2177	  is enabled and the system supports BTI all kernel code including
2178	  modular code must have BTI enabled.
2179
2180config CC_HAS_BRANCH_PROT_PAC_RET_BTI
2181	# GCC 9 or later, clang 8 or later
2182	def_bool $(cc-option,-mbranch-protection=pac-ret+leaf+bti)
2183
2184config ARM64_E0PD
2185	bool "Enable support for E0PD"
2186	default y
2187	help
2188	  E0PD (part of the ARMv8.5 extensions) allows us to ensure
2189	  that EL0 accesses made via TTBR1 always fault in constant time,
2190	  providing similar benefits to KASLR as those provided by KPTI, but
2191	  with lower overhead and without disrupting legitimate access to
2192	  kernel memory such as SPE.
2193
2194	  This option enables E0PD for TTBR1 where available.
2195
2196config ARM64_AS_HAS_MTE
2197	# Initial support for MTE went in binutils 2.32.0, checked with
2198	# ".arch armv8.5-a+memtag" below. However, this was incomplete
2199	# as a late addition to the final architecture spec (LDGM/STGM)
2200	# is only supported in the newer 2.32.x and 2.33 binutils
2201	# versions, hence the extra "stgm" instruction check below.
2202	def_bool $(as-instr,.arch armv8.5-a+memtag\nstgm xzr$(comma)[x0])
2203
2204config ARM64_MTE
2205	bool "Memory Tagging Extension support"
2206	default y
2207	depends on ARM64_AS_HAS_MTE && ARM64_TAGGED_ADDR_ABI
2208	depends on AS_HAS_ARMV8_5
2209	# Required for tag checking in the uaccess routines
2210	select ARCH_HAS_SUBPAGE_FAULTS
2211	select ARCH_USES_HIGH_VMA_FLAGS
2212	select ARCH_USES_PG_ARCH_2
2213	select ARCH_USES_PG_ARCH_3
2214	help
2215	  Memory Tagging (part of the ARMv8.5 Extensions) provides
2216	  architectural support for run-time, always-on detection of
2217	  various classes of memory error to aid with software debugging
2218	  to eliminate vulnerabilities arising from memory-unsafe
2219	  languages.
2220
2221	  This option enables the support for the Memory Tagging
2222	  Extension at EL0 (i.e. for userspace).
2223
2224	  Selecting this option allows the feature to be detected at
2225	  runtime. Any secondary CPU not implementing this feature will
2226	  not be allowed a late bring-up.
2227
2228	  Userspace binaries that want to use this feature must
2229	  explicitly opt in. The mechanism for the userspace is
2230	  described in:
2231
2232	  Documentation/arch/arm64/memory-tagging-extension.rst.
2233
2234endmenu # "ARMv8.5 architectural features"
2235
2236menu "ARMv8.7 architectural features"
2237
2238config ARM64_EPAN
2239	bool "Enable support for Enhanced Privileged Access Never (EPAN)"
2240	default y
2241	help
2242	  Enhanced Privileged Access Never (EPAN) allows Privileged
2243	  Access Never to be used with Execute-only mappings.
2244
2245	  The feature is detected at runtime, and will remain disabled
2246	  if the cpu does not implement the feature.
2247endmenu # "ARMv8.7 architectural features"
2248
2249config AS_HAS_MOPS
2250	def_bool $(as-instr,.arch_extension mops)
2251
2252menu "ARMv8.9 architectural features"
2253
2254config ARM64_POE
2255	prompt "Permission Overlay Extension"
2256	def_bool y
2257	select ARCH_USES_HIGH_VMA_FLAGS
2258	select ARCH_HAS_PKEYS
2259	help
2260	  The Permission Overlay Extension is used to implement Memory
2261	  Protection Keys. Memory Protection Keys provides a mechanism for
2262	  enforcing page-based protections, but without requiring modification
2263	  of the page tables when an application changes protection domains.
2264
2265	  For details, see Documentation/core-api/protection-keys.rst
2266
2267	  If unsure, say y.
2268
2269config ARCH_PKEY_BITS
2270	int
2271	default 3
2272
2273config ARM64_HAFT
2274	bool "Support for Hardware managed Access Flag for Table Descriptors"
2275	depends on ARM64_HW_AFDBM
2276	default y
2277	help
2278	  The ARMv8.9/ARMv9.5 introduces the feature Hardware managed Access
2279	  Flag for Table descriptors. When enabled an architectural executed
2280	  memory access will update the Access Flag in each Table descriptor
2281	  which is accessed during the translation table walk and for which
2282	  the Access Flag is 0. The Access Flag of the Table descriptor use
2283	  the same bit of PTE_AF.
2284
2285	  The feature will only be enabled if all the CPUs in the system
2286	  support this feature. If unsure, say Y.
2287
2288endmenu # "ARMv8.9 architectural features"
2289
2290menu "ARMv9.4 architectural features"
2291
2292config ARM64_GCS
2293	bool "Enable support for Guarded Control Stack (GCS)"
2294	default y
2295	select ARCH_HAS_USER_SHADOW_STACK
2296	select ARCH_USES_HIGH_VMA_FLAGS
2297	help
2298	  Guarded Control Stack (GCS) provides support for a separate
2299	  stack with restricted access which contains only return
2300	  addresses.  This can be used to harden against some attacks
2301	  by comparing return address used by the program with what is
2302	  stored in the GCS, and may also be used to efficiently obtain
2303	  the call stack for applications such as profiling.
2304
2305	  The feature is detected at runtime, and will remain disabled
2306	  if the system does not implement the feature.
2307
2308endmenu # "ARMv9.4 architectural features"
2309
2310config AS_HAS_LSUI
2311	def_bool $(as-instr,.arch_extension lsui)
2312	help
2313	  Supported by LLVM 20+ and binutils 2.45+.
2314
2315menu "ARMv9.6 architectural features"
2316
2317config ARM64_LSUI
2318	bool "Support Unprivileged Load Store Instructions (LSUI)"
2319	default y
2320	depends on AS_HAS_LSUI && !CPU_BIG_ENDIAN
2321	help
2322	  The Unprivileged Load Store Instructions (LSUI) provides
2323	  variants load/store instructions that access user-space memory
2324	  from the kernel without clearing PSTATE.PAN bit.
2325
2326	  This feature is supported by LLVM 20+ and binutils 2.45+.
2327
2328endmenu # "ARMv9.6 architectural feature"
2329
2330config ARM64_SVE
2331	bool "ARM Scalable Vector Extension support"
2332	default y
2333	help
2334	  The Scalable Vector Extension (SVE) is an extension to the AArch64
2335	  execution state which complements and extends the SIMD functionality
2336	  of the base architecture to support much larger vectors and to enable
2337	  additional vectorisation opportunities.
2338
2339	  To enable use of this extension on CPUs that implement it, say Y.
2340
2341	  On CPUs that support the SVE2 extensions, this option will enable
2342	  those too.
2343
2344	  Note that for architectural reasons, firmware _must_ implement SVE
2345	  support when running on SVE capable hardware.  The required support
2346	  is present in:
2347
2348	    * version 1.5 and later of the ARM Trusted Firmware
2349	    * the AArch64 boot wrapper since commit 5e1261e08abf
2350	      ("bootwrapper: SVE: Enable SVE for EL2 and below").
2351
2352	  For other firmware implementations, consult the firmware documentation
2353	  or vendor.
2354
2355	  If you need the kernel to boot on SVE-capable hardware with broken
2356	  firmware, you may need to say N here until you get your firmware
2357	  fixed.  Otherwise, you may experience firmware panics or lockups when
2358	  booting the kernel.  If unsure and you are not observing these
2359	  symptoms, you should assume that it is safe to say Y.
2360
2361config AS_HAS_SME
2362	# Supported by LLVM 13+ and binutils 2.38+
2363	def_bool $(as-instr,.arch_extension sme)
2364
2365config ARM64_SME
2366	bool "ARM Scalable Matrix Extension support"
2367	default y
2368	depends on ARM64_SVE
2369	depends on AS_HAS_SME
2370	help
2371	  The Scalable Matrix Extension (SME) is an extension to the AArch64
2372	  execution state which utilises a substantial subset of the SVE
2373	  instruction set, together with the addition of new architectural
2374	  register state capable of holding two dimensional matrix tiles to
2375	  enable various matrix operations.
2376
2377config ARM64_PSEUDO_NMI
2378	bool "Support for NMI-like interrupts"
2379	select ARM_GIC_V3
2380	help
2381	  Adds support for mimicking Non-Maskable Interrupts through the use of
2382	  GIC interrupt priority. This support requires version 3 or later of
2383	  ARM GIC.
2384
2385	  This high priority configuration for interrupts needs to be
2386	  explicitly enabled by setting the kernel parameter
2387	  "irqchip.gicv3_pseudo_nmi" to 1.
2388
2389	  If unsure, say N
2390
2391if ARM64_PSEUDO_NMI
2392config ARM64_DEBUG_PRIORITY_MASKING
2393	bool "Debug interrupt priority masking"
2394	help
2395	  This adds runtime checks to functions enabling/disabling
2396	  interrupts when using priority masking. The additional checks verify
2397	  the validity of ICC_PMR_EL1 when calling concerned functions.
2398
2399	  If unsure, say N
2400endif # ARM64_PSEUDO_NMI
2401
2402config RELOCATABLE
2403	bool "Build a relocatable kernel image" if EXPERT
2404	select ARCH_HAS_RELR
2405	default y
2406	help
2407	  This builds the kernel as a Position Independent Executable (PIE),
2408	  which retains all relocation metadata required to relocate the
2409	  kernel binary at runtime to a different virtual address than the
2410	  address it was linked at.
2411	  Since AArch64 uses the RELA relocation format, this requires a
2412	  relocation pass at runtime even if the kernel is loaded at the
2413	  same address it was linked at.
2414
2415config RANDOMIZE_BASE
2416	bool "Randomize the address of the kernel image"
2417	select RELOCATABLE
2418	help
2419	  Randomizes the virtual address at which the kernel image is
2420	  loaded, as a security feature that deters exploit attempts
2421	  relying on knowledge of the location of kernel internals.
2422
2423	  It is the bootloader's job to provide entropy, by passing a
2424	  random u64 value in /chosen/kaslr-seed at kernel entry.
2425
2426	  When booting via the UEFI stub, it will invoke the firmware's
2427	  EFI_RNG_PROTOCOL implementation (if available) to supply entropy
2428	  to the kernel proper. In addition, it will randomise the physical
2429	  location of the kernel Image as well.
2430
2431	  If unsure, say N.
2432
2433config RANDOMIZE_MODULE_REGION_FULL
2434	bool "Randomize the module region over a 2 GB range"
2435	depends on RANDOMIZE_BASE
2436	default y
2437	help
2438	  Randomizes the location of the module region inside a 2 GB window
2439	  covering the core kernel. This way, it is less likely for modules
2440	  to leak information about the location of core kernel data structures
2441	  but it does imply that function calls between modules and the core
2442	  kernel will need to be resolved via veneers in the module PLT.
2443
2444	  When this option is not set, the module region will be randomized over
2445	  a limited range that contains the [_stext, _etext] interval of the
2446	  core kernel, so branch relocations are almost always in range unless
2447	  the region is exhausted. In this particular case of region
2448	  exhaustion, modules might be able to fall back to a larger 2GB area.
2449
2450config CC_HAVE_STACKPROTECTOR_SYSREG
2451	def_bool $(cc-option,-mstack-protector-guard=sysreg -mstack-protector-guard-reg=sp_el0 -mstack-protector-guard-offset=0)
2452
2453config STACKPROTECTOR_PER_TASK
2454	def_bool y
2455	depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_SYSREG
2456
2457config UNWIND_PATCH_PAC_INTO_SCS
2458	bool "Enable shadow call stack dynamically using code patching"
2459	depends on CC_IS_CLANG
2460	depends on ARM64_PTR_AUTH_KERNEL && CC_HAS_BRANCH_PROT_PAC_RET
2461	depends on SHADOW_CALL_STACK
2462	select UNWIND_TABLES
2463	select DYNAMIC_SCS
2464
2465config ARM64_CONTPTE
2466	bool "Contiguous PTE mappings for user memory" if EXPERT
2467	depends on TRANSPARENT_HUGEPAGE
2468	default y
2469	help
2470	  When enabled, user mappings are configured using the PTE contiguous
2471	  bit, for any mappings that meet the size and alignment requirements.
2472	  This reduces TLB pressure and improves performance.
2473
2474endmenu # "Kernel Features"
2475
2476menu "Boot options"
2477
2478config ARM64_ACPI_PARKING_PROTOCOL
2479	bool "Enable support for the ARM64 ACPI parking protocol"
2480	depends on ACPI
2481	help
2482	  Enable support for the ARM64 ACPI parking protocol. If disabled
2483	  the kernel will not allow booting through the ARM64 ACPI parking
2484	  protocol even if the corresponding data is present in the ACPI
2485	  MADT table.
2486
2487config CMDLINE
2488	string "Default kernel command string"
2489	default ""
2490	help
2491	  Provide a set of default command-line options at build time by
2492	  entering them here. As a minimum, you should specify the
2493	  root device (e.g. root=/dev/nfs).
2494
2495choice
2496	prompt "Kernel command line type"
2497	depends on CMDLINE != ""
2498	default CMDLINE_FROM_BOOTLOADER
2499	help
2500	  Choose how the kernel will handle the provided default kernel
2501	  command line string.
2502
2503config CMDLINE_FROM_BOOTLOADER
2504	bool "Use bootloader kernel arguments if available"
2505	help
2506	  Uses the command-line options passed by the boot loader. If
2507	  the boot loader doesn't provide any, the default kernel command
2508	  string provided in CMDLINE will be used.
2509
2510config CMDLINE_FORCE
2511	bool "Always use the default kernel command string"
2512	help
2513	  Always use the default kernel command string, even if the boot
2514	  loader passes other arguments to the kernel.
2515	  This is useful if you cannot or don't want to change the
2516	  command-line options your boot loader passes to the kernel.
2517
2518endchoice
2519
2520config EFI_STUB
2521	bool
2522
2523config EFI
2524	bool "UEFI runtime support"
2525	depends on OF && !CPU_BIG_ENDIAN
2526	depends on KERNEL_MODE_NEON
2527	select ARCH_SUPPORTS_ACPI
2528	select LIBFDT
2529	select UCS2_STRING
2530	select EFI_PARAMS_FROM_FDT
2531	select EFI_RUNTIME_WRAPPERS
2532	select EFI_STUB
2533	select EFI_GENERIC_STUB
2534	imply IMA_SECURE_AND_OR_TRUSTED_BOOT
2535	default y
2536	help
2537	  This option provides support for runtime services provided
2538	  by UEFI firmware (such as non-volatile variables, realtime
2539	  clock, and platform reset). A UEFI stub is also provided to
2540	  allow the kernel to be booted as an EFI application. This
2541	  is only useful on systems that have UEFI firmware.
2542
2543config COMPRESSED_INSTALL
2544	bool "Install compressed image by default"
2545	help
2546	  This makes the regular "make install" install the compressed
2547	  image we built, not the legacy uncompressed one.
2548
2549	  You can check that a compressed image works for you by doing
2550	  "make zinstall" first, and verifying that everything is fine
2551	  in your environment before making "make install" do this for
2552	  you.
2553
2554config DMI
2555	bool "Enable support for SMBIOS (DMI) tables"
2556	depends on EFI
2557	default y
2558	help
2559	  This enables SMBIOS/DMI feature for systems.
2560
2561	  This option is only useful on systems that have UEFI firmware.
2562	  However, even with this option, the resultant kernel should
2563	  continue to boot on existing non-UEFI platforms.
2564
2565endmenu # "Boot options"
2566
2567menu "Power management options"
2568
2569source "kernel/power/Kconfig"
2570
2571config ARCH_HIBERNATION_POSSIBLE
2572	def_bool y
2573	depends on CPU_PM
2574
2575config ARCH_HIBERNATION_HEADER
2576	def_bool y
2577	depends on HIBERNATION
2578
2579config ARCH_SUSPEND_POSSIBLE
2580	def_bool y
2581
2582endmenu # "Power management options"
2583
2584menu "CPU Power Management"
2585
2586source "drivers/cpuidle/Kconfig"
2587
2588source "drivers/cpufreq/Kconfig"
2589
2590endmenu # "CPU Power Management"
2591
2592source "drivers/acpi/Kconfig"
2593
2594source "arch/arm64/kvm/Kconfig"
2595
2596source "kernel/livepatch/Kconfig"
2597