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1# SPDX-License-Identifier: GPL-2.0-only
2config ARM64
3	def_bool y
4	select ACPI_CCA_REQUIRED if ACPI
5	select ACPI_GENERIC_GSI if ACPI
6	select ACPI_GTDT if ACPI
7	select ACPI_IORT if ACPI
8	select ACPI_REDUCED_HARDWARE_ONLY if ACPI
9	select ACPI_MCFG if (ACPI && PCI)
10	select ACPI_SPCR_TABLE if ACPI
11	select ACPI_PPTT if ACPI
12	select ARCH_CLOCKSOURCE_DATA
13	select ARCH_HAS_DEBUG_VIRTUAL
14	select ARCH_HAS_DEVMEM_IS_ALLOWED
15	select ARCH_HAS_DMA_COHERENT_TO_PFN
16	select ARCH_HAS_DMA_PREP_COHERENT
17	select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI
18	select ARCH_HAS_FAST_MULTIPLIER
19	select ARCH_HAS_FORTIFY_SOURCE
20	select ARCH_HAS_GCOV_PROFILE_ALL
21	select ARCH_HAS_GIGANTIC_PAGE
22	select ARCH_HAS_KCOV
23	select ARCH_HAS_KEEPINITRD
24	select ARCH_HAS_MEMBARRIER_SYNC_CORE
25	select ARCH_HAS_PTE_DEVMAP
26	select ARCH_HAS_PTE_SPECIAL
27	select ARCH_HAS_SETUP_DMA_OPS
28	select ARCH_HAS_SET_DIRECT_MAP
29	select ARCH_HAS_SET_MEMORY
30	select ARCH_HAS_STRICT_KERNEL_RWX
31	select ARCH_HAS_STRICT_MODULE_RWX
32	select ARCH_HAS_SYNC_DMA_FOR_DEVICE
33	select ARCH_HAS_SYNC_DMA_FOR_CPU
34	select ARCH_HAS_SYSCALL_WRAPPER
35	select ARCH_HAS_TEARDOWN_DMA_OPS if IOMMU_SUPPORT
36	select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
37	select ARCH_HAVE_NMI_SAFE_CMPXCHG
38	select ARCH_INLINE_READ_LOCK if !PREEMPT
39	select ARCH_INLINE_READ_LOCK_BH if !PREEMPT
40	select ARCH_INLINE_READ_LOCK_IRQ if !PREEMPT
41	select ARCH_INLINE_READ_LOCK_IRQSAVE if !PREEMPT
42	select ARCH_INLINE_READ_UNLOCK if !PREEMPT
43	select ARCH_INLINE_READ_UNLOCK_BH if !PREEMPT
44	select ARCH_INLINE_READ_UNLOCK_IRQ if !PREEMPT
45	select ARCH_INLINE_READ_UNLOCK_IRQRESTORE if !PREEMPT
46	select ARCH_INLINE_WRITE_LOCK if !PREEMPT
47	select ARCH_INLINE_WRITE_LOCK_BH if !PREEMPT
48	select ARCH_INLINE_WRITE_LOCK_IRQ if !PREEMPT
49	select ARCH_INLINE_WRITE_LOCK_IRQSAVE if !PREEMPT
50	select ARCH_INLINE_WRITE_UNLOCK if !PREEMPT
51	select ARCH_INLINE_WRITE_UNLOCK_BH if !PREEMPT
52	select ARCH_INLINE_WRITE_UNLOCK_IRQ if !PREEMPT
53	select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE if !PREEMPT
54	select ARCH_INLINE_SPIN_TRYLOCK if !PREEMPT
55	select ARCH_INLINE_SPIN_TRYLOCK_BH if !PREEMPT
56	select ARCH_INLINE_SPIN_LOCK if !PREEMPT
57	select ARCH_INLINE_SPIN_LOCK_BH if !PREEMPT
58	select ARCH_INLINE_SPIN_LOCK_IRQ if !PREEMPT
59	select ARCH_INLINE_SPIN_LOCK_IRQSAVE if !PREEMPT
60	select ARCH_INLINE_SPIN_UNLOCK if !PREEMPT
61	select ARCH_INLINE_SPIN_UNLOCK_BH if !PREEMPT
62	select ARCH_INLINE_SPIN_UNLOCK_IRQ if !PREEMPT
63	select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE if !PREEMPT
64	select ARCH_KEEP_MEMBLOCK
65	select ARCH_USE_CMPXCHG_LOCKREF
66	select ARCH_USE_QUEUED_RWLOCKS
67	select ARCH_USE_QUEUED_SPINLOCKS
68	select ARCH_SUPPORTS_MEMORY_FAILURE
69	select ARCH_SUPPORTS_SHADOW_CALL_STACK if CC_HAVE_SHADOW_CALL_STACK
70	select ARCH_SUPPORTS_LTO_CLANG
71	select ARCH_SUPPORTS_THINLTO
72	select ARCH_SUPPORTS_ATOMIC_RMW
73	select ARCH_SUPPORTS_INT128 if GCC_VERSION >= 50000 || CC_IS_CLANG
74	select ARCH_SUPPORTS_NUMA_BALANCING
75	select ARCH_WANT_COMPAT_IPC_PARSE_VERSION if COMPAT
76	select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT
77	select ARCH_WANT_FRAME_POINTERS
78	select ARCH_WANT_HUGE_PMD_SHARE if ARM64_4K_PAGES || (ARM64_16K_PAGES && !ARM64_VA_BITS_36)
79	select ARCH_HAS_UBSAN_SANITIZE_ALL
80	select ARM_AMBA
81	select ARM_ARCH_TIMER
82	select ARM_GIC
83	select AUDIT_ARCH_COMPAT_GENERIC
84	select ARM_GIC_V2M if PCI
85	select ARM_GIC_V3
86	select ARM_GIC_V3_ITS if PCI
87	select ARM_PSCI_FW
88	select BUILDTIME_EXTABLE_SORT
89	select CLONE_BACKWARDS
90	select COMMON_CLK
91	select CPU_PM if (SUSPEND || CPU_IDLE)
92	select CRC32
93	select DCACHE_WORD_ACCESS
94	select DMA_DIRECT_REMAP
95	select EDAC_SUPPORT
96	select FRAME_POINTER
97	select GENERIC_ALLOCATOR
98	select GENERIC_ARCH_TOPOLOGY
99	select GENERIC_CLOCKEVENTS
100	select GENERIC_CLOCKEVENTS_BROADCAST
101	select GENERIC_CPU_AUTOPROBE
102	select GENERIC_CPU_VULNERABILITIES
103	select GENERIC_EARLY_IOREMAP
104	select GENERIC_IDLE_POLL_SETUP
105	select GENERIC_IRQ_MULTI_HANDLER
106	select GENERIC_IRQ_PROBE
107	select GENERIC_IRQ_SHOW
108	select GENERIC_IRQ_SHOW_LEVEL
109	select GENERIC_PCI_IOMAP
110	select GENERIC_SCHED_CLOCK
111	select GENERIC_SMP_IDLE_THREAD
112	select GENERIC_STRNCPY_FROM_USER
113	select GENERIC_STRNLEN_USER
114	select GENERIC_TIME_VSYSCALL
115	select GENERIC_GETTIMEOFDAY
116	select HANDLE_DOMAIN_IRQ
117	select HARDIRQS_SW_RESEND
118	select HAVE_PCI
119	select HAVE_ACPI_APEI if (ACPI && EFI)
120	select HAVE_ALIGNED_STRUCT_PAGE if SLUB
121	select HAVE_ARCH_AUDITSYSCALL
122	select HAVE_ARCH_BITREVERSE
123	select HAVE_ARCH_HUGE_VMAP
124	select HAVE_ARCH_JUMP_LABEL
125	select HAVE_ARCH_JUMP_LABEL_RELATIVE
126	select HAVE_ARCH_KASAN if !(ARM64_16K_PAGES && ARM64_VA_BITS_48)
127	select HAVE_ARCH_KASAN_SW_TAGS if HAVE_ARCH_KASAN
128	select HAVE_ARCH_KGDB
129	select HAVE_ARCH_MMAP_RND_BITS
130	select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT
131	select HAVE_ARCH_PREL32_RELOCATIONS if !LTO_CLANG
132	select HAVE_ARCH_SECCOMP_FILTER
133	select HAVE_ARCH_STACKLEAK
134	select HAVE_ARCH_THREAD_STRUCT_WHITELIST
135	select HAVE_ARCH_TRACEHOOK
136	select HAVE_ARCH_TRANSPARENT_HUGEPAGE
137	select HAVE_ARCH_VMAP_STACK
138	select HAVE_ARM_SMCCC
139	select HAVE_ASM_MODVERSIONS
140	select HAVE_EBPF_JIT
141	select HAVE_C_RECORDMCOUNT
142	select HAVE_CMPXCHG_DOUBLE
143	select HAVE_CMPXCHG_LOCAL
144	select HAVE_CONTEXT_TRACKING
145	select HAVE_COPY_THREAD_TLS
146	select HAVE_DEBUG_BUGVERBOSE
147	select HAVE_DEBUG_KMEMLEAK
148	select HAVE_DMA_CONTIGUOUS
149	select HAVE_DYNAMIC_FTRACE
150	select HAVE_EFFICIENT_UNALIGNED_ACCESS
151	select HAVE_FAST_GUP
152	select HAVE_FTRACE_MCOUNT_RECORD
153	select HAVE_FUNCTION_TRACER
154	select HAVE_FUNCTION_ERROR_INJECTION
155	select HAVE_FUNCTION_GRAPH_TRACER if !SHADOW_CALL_STACK
156	select HAVE_GCC_PLUGINS
157	select HAVE_HW_BREAKPOINT if PERF_EVENTS
158	select HAVE_IRQ_TIME_ACCOUNTING
159	select HAVE_MEMBLOCK_NODE_MAP if NUMA
160	select HAVE_NMI
161	select HAVE_PATA_PLATFORM
162	select HAVE_PERF_EVENTS
163	select HAVE_PERF_REGS
164	select HAVE_PERF_USER_STACK_DUMP
165	select HAVE_REGS_AND_STACK_ACCESS_API
166	select HAVE_FUNCTION_ARG_ACCESS_API
167	select HAVE_RCU_TABLE_FREE
168	select HAVE_RSEQ
169	select HAVE_STACKPROTECTOR
170	select HAVE_SYSCALL_TRACEPOINTS
171	select HAVE_KPROBES
172	select HAVE_KRETPROBES
173	select HAVE_GENERIC_VDSO
174	select IOMMU_DMA if IOMMU_SUPPORT
175	select IRQ_DOMAIN
176	select IRQ_FORCED_THREADING
177	select MODULES_USE_ELF_RELA
178	select NEED_DMA_MAP_STATE
179	select NEED_SG_DMA_LENGTH
180	select OF
181	select OF_EARLY_FLATTREE
182	select PCI_DOMAINS_GENERIC if PCI
183	select PCI_ECAM if (ACPI && PCI)
184	select PCI_SYSCALL if PCI
185	select POWER_RESET
186	select POWER_SUPPLY
187	select SPARSE_IRQ
188	select SWIOTLB
189	select SYSCTL_EXCEPTION_TRACE
190	select THREAD_INFO_IN_TASK
191	help
192	  ARM 64-bit (AArch64) Linux support.
193
194config 64BIT
195	def_bool y
196
197config MMU
198	def_bool y
199
200config ARM64_PAGE_SHIFT
201	int
202	default 16 if ARM64_64K_PAGES
203	default 14 if ARM64_16K_PAGES
204	default 12
205
206config ARM64_CONT_SHIFT
207	int
208	default 5 if ARM64_64K_PAGES
209	default 7 if ARM64_16K_PAGES
210	default 4
211
212config ARCH_MMAP_RND_BITS_MIN
213       default 14 if ARM64_64K_PAGES
214       default 16 if ARM64_16K_PAGES
215       default 18
216
217# max bits determined by the following formula:
218#  VA_BITS - PAGE_SHIFT - 3
219config ARCH_MMAP_RND_BITS_MAX
220       default 19 if ARM64_VA_BITS=36
221       default 24 if ARM64_VA_BITS=39
222       default 27 if ARM64_VA_BITS=42
223       default 30 if ARM64_VA_BITS=47
224       default 29 if ARM64_VA_BITS=48 && ARM64_64K_PAGES
225       default 31 if ARM64_VA_BITS=48 && ARM64_16K_PAGES
226       default 33 if ARM64_VA_BITS=48
227       default 14 if ARM64_64K_PAGES
228       default 16 if ARM64_16K_PAGES
229       default 18
230
231config ARCH_MMAP_RND_COMPAT_BITS_MIN
232       default 7 if ARM64_64K_PAGES
233       default 9 if ARM64_16K_PAGES
234       default 11
235
236config ARCH_MMAP_RND_COMPAT_BITS_MAX
237       default 16
238
239config NO_IOPORT_MAP
240	def_bool y if !PCI
241
242config STACKTRACE_SUPPORT
243	def_bool y
244
245config ILLEGAL_POINTER_VALUE
246	hex
247	default 0xdead000000000000
248
249config LOCKDEP_SUPPORT
250	def_bool y
251
252config TRACE_IRQFLAGS_SUPPORT
253	def_bool y
254
255config GENERIC_BUG
256	def_bool y
257	depends on BUG
258
259config GENERIC_BUG_RELATIVE_POINTERS
260	def_bool y
261	depends on GENERIC_BUG
262
263config GENERIC_HWEIGHT
264	def_bool y
265
266config GENERIC_CSUM
267        def_bool y
268
269config GENERIC_CALIBRATE_DELAY
270	def_bool y
271
272config ZONE_DMA32
273	bool "Support DMA32 zone" if EXPERT
274	default y
275
276config ARCH_ENABLE_MEMORY_HOTPLUG
277	def_bool y
278
279config SMP
280	def_bool y
281
282config KERNEL_MODE_NEON
283	def_bool y
284
285config FIX_EARLYCON_MEM
286	def_bool y
287
288config PGTABLE_LEVELS
289	int
290	default 2 if ARM64_16K_PAGES && ARM64_VA_BITS_36
291	default 2 if ARM64_64K_PAGES && ARM64_VA_BITS_42
292	default 3 if ARM64_64K_PAGES && (ARM64_VA_BITS_48 || ARM64_VA_BITS_52)
293	default 3 if ARM64_4K_PAGES && ARM64_VA_BITS_39
294	default 3 if ARM64_16K_PAGES && ARM64_VA_BITS_47
295	default 4 if !ARM64_64K_PAGES && ARM64_VA_BITS_48
296
297config ARCH_SUPPORTS_UPROBES
298	def_bool y
299
300config ARCH_PROC_KCORE_TEXT
301	def_bool y
302
303config KASAN_SHADOW_OFFSET
304	hex
305	depends on KASAN
306	default 0xdfffa00000000000 if (ARM64_VA_BITS_48 || ARM64_VA_BITS_52) && !KASAN_SW_TAGS
307	default 0xdfffd00000000000 if ARM64_VA_BITS_47 && !KASAN_SW_TAGS
308	default 0xdffffe8000000000 if ARM64_VA_BITS_42 && !KASAN_SW_TAGS
309	default 0xdfffffd000000000 if ARM64_VA_BITS_39 && !KASAN_SW_TAGS
310	default 0xdffffffa00000000 if ARM64_VA_BITS_36 && !KASAN_SW_TAGS
311	default 0xefff900000000000 if (ARM64_VA_BITS_48 || ARM64_VA_BITS_52) && KASAN_SW_TAGS
312	default 0xefffc80000000000 if ARM64_VA_BITS_47 && KASAN_SW_TAGS
313	default 0xeffffe4000000000 if ARM64_VA_BITS_42 && KASAN_SW_TAGS
314	default 0xefffffc800000000 if ARM64_VA_BITS_39 && KASAN_SW_TAGS
315	default 0xeffffff900000000 if ARM64_VA_BITS_36 && KASAN_SW_TAGS
316	default 0xffffffffffffffff
317
318source "arch/arm64/Kconfig.platforms"
319
320menu "Kernel Features"
321
322menu "ARM errata workarounds via the alternatives framework"
323
324config ARM64_WORKAROUND_CLEAN_CACHE
325	bool
326
327config ARM64_ERRATUM_826319
328	bool "Cortex-A53: 826319: System might deadlock if a write cannot complete until read data is accepted"
329	default y
330	select ARM64_WORKAROUND_CLEAN_CACHE
331	help
332	  This option adds an alternative code sequence to work around ARM
333	  erratum 826319 on Cortex-A53 parts up to r0p2 with an AMBA 4 ACE or
334	  AXI master interface and an L2 cache.
335
336	  If a Cortex-A53 uses an AMBA AXI4 ACE interface to other processors
337	  and is unable to accept a certain write via this interface, it will
338	  not progress on read data presented on the read data channel and the
339	  system can deadlock.
340
341	  The workaround promotes data cache clean instructions to
342	  data cache clean-and-invalidate.
343	  Please note that this does not necessarily enable the workaround,
344	  as it depends on the alternative framework, which will only patch
345	  the kernel if an affected CPU is detected.
346
347	  If unsure, say Y.
348
349config ARM64_ERRATUM_827319
350	bool "Cortex-A53: 827319: Data cache clean instructions might cause overlapping transactions to the interconnect"
351	default y
352	select ARM64_WORKAROUND_CLEAN_CACHE
353	help
354	  This option adds an alternative code sequence to work around ARM
355	  erratum 827319 on Cortex-A53 parts up to r0p2 with an AMBA 5 CHI
356	  master interface and an L2 cache.
357
358	  Under certain conditions this erratum can cause a clean line eviction
359	  to occur at the same time as another transaction to the same address
360	  on the AMBA 5 CHI interface, which can cause data corruption if the
361	  interconnect reorders the two transactions.
362
363	  The workaround promotes data cache clean instructions to
364	  data cache clean-and-invalidate.
365	  Please note that this does not necessarily enable the workaround,
366	  as it depends on the alternative framework, which will only patch
367	  the kernel if an affected CPU is detected.
368
369	  If unsure, say Y.
370
371config ARM64_ERRATUM_824069
372	bool "Cortex-A53: 824069: Cache line might not be marked as clean after a CleanShared snoop"
373	default y
374	select ARM64_WORKAROUND_CLEAN_CACHE
375	help
376	  This option adds an alternative code sequence to work around ARM
377	  erratum 824069 on Cortex-A53 parts up to r0p2 when it is connected
378	  to a coherent interconnect.
379
380	  If a Cortex-A53 processor is executing a store or prefetch for
381	  write instruction at the same time as a processor in another
382	  cluster is executing a cache maintenance operation to the same
383	  address, then this erratum might cause a clean cache line to be
384	  incorrectly marked as dirty.
385
386	  The workaround promotes data cache clean instructions to
387	  data cache clean-and-invalidate.
388	  Please note that this option does not necessarily enable the
389	  workaround, as it depends on the alternative framework, which will
390	  only patch the kernel if an affected CPU is detected.
391
392	  If unsure, say Y.
393
394config ARM64_ERRATUM_819472
395	bool "Cortex-A53: 819472: Store exclusive instructions might cause data corruption"
396	default y
397	select ARM64_WORKAROUND_CLEAN_CACHE
398	help
399	  This option adds an alternative code sequence to work around ARM
400	  erratum 819472 on Cortex-A53 parts up to r0p1 with an L2 cache
401	  present when it is connected to a coherent interconnect.
402
403	  If the processor is executing a load and store exclusive sequence at
404	  the same time as a processor in another cluster is executing a cache
405	  maintenance operation to the same address, then this erratum might
406	  cause data corruption.
407
408	  The workaround promotes data cache clean instructions to
409	  data cache clean-and-invalidate.
410	  Please note that this does not necessarily enable the workaround,
411	  as it depends on the alternative framework, which will only patch
412	  the kernel if an affected CPU is detected.
413
414	  If unsure, say Y.
415
416config ARM64_ERRATUM_832075
417	bool "Cortex-A57: 832075: possible deadlock on mixing exclusive memory accesses with device loads"
418	default y
419	help
420	  This option adds an alternative code sequence to work around ARM
421	  erratum 832075 on Cortex-A57 parts up to r1p2.
422
423	  Affected Cortex-A57 parts might deadlock when exclusive load/store
424	  instructions to Write-Back memory are mixed with Device loads.
425
426	  The workaround is to promote device loads to use Load-Acquire
427	  semantics.
428	  Please note that this does not necessarily enable the workaround,
429	  as it depends on the alternative framework, which will only patch
430	  the kernel if an affected CPU is detected.
431
432	  If unsure, say Y.
433
434config ARM64_ERRATUM_834220
435	bool "Cortex-A57: 834220: Stage 2 translation fault might be incorrectly reported in presence of a Stage 1 fault"
436	depends on KVM
437	default y
438	help
439	  This option adds an alternative code sequence to work around ARM
440	  erratum 834220 on Cortex-A57 parts up to r1p2.
441
442	  Affected Cortex-A57 parts might report a Stage 2 translation
443	  fault as the result of a Stage 1 fault for load crossing a
444	  page boundary when there is a permission or device memory
445	  alignment fault at Stage 1 and a translation fault at Stage 2.
446
447	  The workaround is to verify that the Stage 1 translation
448	  doesn't generate a fault before handling the Stage 2 fault.
449	  Please note that this does not necessarily enable the workaround,
450	  as it depends on the alternative framework, which will only patch
451	  the kernel if an affected CPU is detected.
452
453	  If unsure, say Y.
454
455config ARM64_ERRATUM_845719
456	bool "Cortex-A53: 845719: a load might read incorrect data"
457	depends on COMPAT
458	default y
459	help
460	  This option adds an alternative code sequence to work around ARM
461	  erratum 845719 on Cortex-A53 parts up to r0p4.
462
463	  When running a compat (AArch32) userspace on an affected Cortex-A53
464	  part, a load at EL0 from a virtual address that matches the bottom 32
465	  bits of the virtual address used by a recent load at (AArch64) EL1
466	  might return incorrect data.
467
468	  The workaround is to write the contextidr_el1 register on exception
469	  return to a 32-bit task.
470	  Please note that this does not necessarily enable the workaround,
471	  as it depends on the alternative framework, which will only patch
472	  the kernel if an affected CPU is detected.
473
474	  If unsure, say Y.
475
476config ARM64_ERRATUM_843419
477	bool "Cortex-A53: 843419: A load or store might access an incorrect address"
478	default y
479	select ARM64_MODULE_PLTS if MODULES
480	help
481	  This option links the kernel with '--fix-cortex-a53-843419' and
482	  enables PLT support to replace certain ADRP instructions, which can
483	  cause subsequent memory accesses to use an incorrect address on
484	  Cortex-A53 parts up to r0p4.
485
486	  If unsure, say Y.
487
488config ARM64_ERRATUM_1024718
489	bool "Cortex-A55: 1024718: Update of DBM/AP bits without break before make might result in incorrect update"
490	default y
491	help
492	  This option adds a workaround for ARM Cortex-A55 Erratum 1024718.
493
494	  Affected Cortex-A55 cores (all revisions) could cause incorrect
495	  update of the hardware dirty bit when the DBM/AP bits are updated
496	  without a break-before-make. The workaround is to disable the usage
497	  of hardware DBM locally on the affected cores. CPUs not affected by
498	  this erratum will continue to use the feature.
499
500	  If unsure, say Y.
501
502config ARM64_ERRATUM_1418040
503	bool "Cortex-A76/Neoverse-N1: MRC read following MRRC read of specific Generic Timer in AArch32 might give incorrect result"
504	default y
505	depends on COMPAT
506	help
507	  This option adds a workaround for ARM Cortex-A76/Neoverse-N1
508	  errata 1188873 and 1418040.
509
510	  Affected Cortex-A76/Neoverse-N1 cores (r0p0 to r3p1) could
511	  cause register corruption when accessing the timer registers
512	  from AArch32 userspace.
513
514	  If unsure, say Y.
515
516config ARM64_ERRATUM_1165522
517	bool "Cortex-A76: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation"
518	default y
519	help
520	  This option adds a workaround for ARM Cortex-A76 erratum 1165522.
521
522	  Affected Cortex-A76 cores (r0p0, r1p0, r2p0) could end-up with
523	  corrupted TLBs by speculating an AT instruction during a guest
524	  context switch.
525
526	  If unsure, say Y.
527
528config ARM64_ERRATUM_1286807
529	bool "Cortex-A76: Modification of the translation table for a virtual address might lead to read-after-read ordering violation"
530	default y
531	select ARM64_WORKAROUND_REPEAT_TLBI
532	help
533	  This option adds a workaround for ARM Cortex-A76 erratum 1286807.
534
535	  On the affected Cortex-A76 cores (r0p0 to r3p0), if a virtual
536	  address for a cacheable mapping of a location is being
537	  accessed by a core while another core is remapping the virtual
538	  address to a new physical page using the recommended
539	  break-before-make sequence, then under very rare circumstances
540	  TLBI+DSB completes before a read using the translation being
541	  invalidated has been observed by other observers. The
542	  workaround repeats the TLBI+DSB operation.
543
544	  If unsure, say Y.
545
546config ARM64_ERRATUM_1463225
547	bool "Cortex-A76: Software Step might prevent interrupt recognition"
548	default y
549	help
550	  This option adds a workaround for Arm Cortex-A76 erratum 1463225.
551
552	  On the affected Cortex-A76 cores (r0p0 to r3p1), software stepping
553	  of a system call instruction (SVC) can prevent recognition of
554	  subsequent interrupts when software stepping is disabled in the
555	  exception handler of the system call and either kernel debugging
556	  is enabled or VHE is in use.
557
558	  Work around the erratum by triggering a dummy step exception
559	  when handling a system call from a task that is being stepped
560	  in a VHE configuration of the kernel.
561
562	  If unsure, say Y.
563
564config ARM64_ERRATUM_1542419
565	bool "Neoverse-N1: workaround mis-ordering of instruction fetches"
566	default y
567	help
568	  This option adds a workaround for ARM Neoverse-N1 erratum
569	  1542419.
570
571	  Affected Neoverse-N1 cores could execute a stale instruction when
572	  modified by another CPU. The workaround depends on a firmware
573	  counterpart.
574
575	  Workaround the issue by hiding the DIC feature from EL0. This
576	  forces user-space to perform cache maintenance.
577
578	  If unsure, say Y.
579
580config ARM64_ERRATUM_1742098
581	bool "Cortex-A57/A72: 1742098: ELR recorded incorrectly on interrupt taken between cryptographic instructions in a sequence"
582	depends on COMPAT
583	default y
584	help
585	  This option removes the AES hwcap for aarch32 user-space to
586	  workaround erratum 1742098 on Cortex-A57 and Cortex-A72.
587
588	  Affected parts may corrupt the AES state if an interrupt is
589	  taken between a pair of AES instructions. These instructions
590	  are only present if the cryptography extensions are present.
591	  All software should have a fallback implementation for CPUs
592	  that don't implement the cryptography extensions.
593
594	  If unsure, say Y.
595
596config CAVIUM_ERRATUM_22375
597	bool "Cavium erratum 22375, 24313"
598	default y
599	help
600	  Enable workaround for errata 22375 and 24313.
601
602	  This implements two gicv3-its errata workarounds for ThunderX. Both
603	  with a small impact affecting only ITS table allocation.
604
605	    erratum 22375: only alloc 8MB table size
606	    erratum 24313: ignore memory access type
607
608	  The fixes are in ITS initialization and basically ignore memory access
609	  type and table size provided by the TYPER and BASER registers.
610
611	  If unsure, say Y.
612
613config CAVIUM_ERRATUM_23144
614	bool "Cavium erratum 23144: ITS SYNC hang on dual socket system"
615	depends on NUMA
616	default y
617	help
618	  ITS SYNC command hang for cross node io and collections/cpu mapping.
619
620	  If unsure, say Y.
621
622config CAVIUM_ERRATUM_23154
623	bool "Cavium erratum 23154: Access to ICC_IAR1_EL1 is not sync'ed"
624	default y
625	help
626	  The gicv3 of ThunderX requires a modified version for
627	  reading the IAR status to ensure data synchronization
628	  (access to icc_iar1_el1 is not sync'ed before and after).
629
630	  If unsure, say Y.
631
632config CAVIUM_ERRATUM_27456
633	bool "Cavium erratum 27456: Broadcast TLBI instructions may cause icache corruption"
634	default y
635	help
636	  On ThunderX T88 pass 1.x through 2.1 parts, broadcast TLBI
637	  instructions may cause the icache to become corrupted if it
638	  contains data for a non-current ASID.  The fix is to
639	  invalidate the icache when changing the mm context.
640
641	  If unsure, say Y.
642
643config CAVIUM_ERRATUM_30115
644	bool "Cavium erratum 30115: Guest may disable interrupts in host"
645	default y
646	help
647	  On ThunderX T88 pass 1.x through 2.2, T81 pass 1.0 through
648	  1.2, and T83 Pass 1.0, KVM guest execution may disable
649	  interrupts in host. Trapping both GICv3 group-0 and group-1
650	  accesses sidesteps the issue.
651
652	  If unsure, say Y.
653
654config CAVIUM_TX2_ERRATUM_219
655	bool "Cavium ThunderX2 erratum 219: PRFM between TTBR change and ISB fails"
656	default y
657	help
658	  On Cavium ThunderX2, a load, store or prefetch instruction between a
659	  TTBR update and the corresponding context synchronizing operation can
660	  cause a spurious Data Abort to be delivered to any hardware thread in
661	  the CPU core.
662
663	  Work around the issue by avoiding the problematic code sequence and
664	  trapping KVM guest TTBRx_EL1 writes to EL2 when SMT is enabled. The
665	  trap handler performs the corresponding register access, skips the
666	  instruction and ensures context synchronization by virtue of the
667	  exception return.
668
669	  If unsure, say Y.
670
671config QCOM_FALKOR_ERRATUM_1003
672	bool "Falkor E1003: Incorrect translation due to ASID change"
673	default y
674	help
675	  On Falkor v1, an incorrect ASID may be cached in the TLB when ASID
676	  and BADDR are changed together in TTBRx_EL1. Since we keep the ASID
677	  in TTBR1_EL1, this situation only occurs in the entry trampoline and
678	  then only for entries in the walk cache, since the leaf translation
679	  is unchanged. Work around the erratum by invalidating the walk cache
680	  entries for the trampoline before entering the kernel proper.
681
682config ARM64_WORKAROUND_REPEAT_TLBI
683	bool
684
685config QCOM_FALKOR_ERRATUM_1009
686	bool "Falkor E1009: Prematurely complete a DSB after a TLBI"
687	default y
688	select ARM64_WORKAROUND_REPEAT_TLBI
689	help
690	  On Falkor v1, the CPU may prematurely complete a DSB following a
691	  TLBI xxIS invalidate maintenance operation. Repeat the TLBI operation
692	  one more time to fix the issue.
693
694	  If unsure, say Y.
695
696config QCOM_QDF2400_ERRATUM_0065
697	bool "QDF2400 E0065: Incorrect GITS_TYPER.ITT_Entry_size"
698	default y
699	help
700	  On Qualcomm Datacenter Technologies QDF2400 SoC, ITS hardware reports
701	  ITE size incorrectly. The GITS_TYPER.ITT_Entry_size field should have
702	  been indicated as 16Bytes (0xf), not 8Bytes (0x7).
703
704	  If unsure, say Y.
705
706config SOCIONEXT_SYNQUACER_PREITS
707	bool "Socionext Synquacer: Workaround for GICv3 pre-ITS"
708	default y
709	help
710	  Socionext Synquacer SoCs implement a separate h/w block to generate
711	  MSI doorbell writes with non-zero values for the device ID.
712
713	  If unsure, say Y.
714
715config HISILICON_ERRATUM_161600802
716	bool "Hip07 161600802: Erroneous redistributor VLPI base"
717	default y
718	help
719	  The HiSilicon Hip07 SoC uses the wrong redistributor base
720	  when issued ITS commands such as VMOVP and VMAPP, and requires
721	  a 128kB offset to be applied to the target address in this commands.
722
723	  If unsure, say Y.
724
725config QCOM_FALKOR_ERRATUM_E1041
726	bool "Falkor E1041: Speculative instruction fetches might cause errant memory access"
727	default y
728	help
729	  Falkor CPU may speculatively fetch instructions from an improper
730	  memory location when MMU translation is changed from SCTLR_ELn[M]=1
731	  to SCTLR_ELn[M]=0. Prefix an ISB instruction to fix the problem.
732
733	  If unsure, say Y.
734
735config FUJITSU_ERRATUM_010001
736	bool "Fujitsu-A64FX erratum E#010001: Undefined fault may occur wrongly"
737	default y
738	help
739	  This option adds a workaround for Fujitsu-A64FX erratum E#010001.
740	  On some variants of the Fujitsu-A64FX cores ver(1.0, 1.1), memory
741	  accesses may cause undefined fault (Data abort, DFSC=0b111111).
742	  This fault occurs under a specific hardware condition when a
743	  load/store instruction performs an address translation using:
744	  case-1  TTBR0_EL1 with TCR_EL1.NFD0 == 1.
745	  case-2  TTBR0_EL2 with TCR_EL2.NFD0 == 1.
746	  case-3  TTBR1_EL1 with TCR_EL1.NFD1 == 1.
747	  case-4  TTBR1_EL2 with TCR_EL2.NFD1 == 1.
748
749	  The workaround is to ensure these bits are clear in TCR_ELx.
750	  The workaround only affects the Fujitsu-A64FX.
751
752	  If unsure, say Y.
753
754endmenu
755
756
757choice
758	prompt "Page size"
759	default ARM64_4K_PAGES
760	help
761	  Page size (translation granule) configuration.
762
763config ARM64_4K_PAGES
764	bool "4KB"
765	help
766	  This feature enables 4KB pages support.
767
768config ARM64_16K_PAGES
769	bool "16KB"
770	help
771	  The system will use 16KB pages support. AArch32 emulation
772	  requires applications compiled with 16K (or a multiple of 16K)
773	  aligned segments.
774
775config ARM64_64K_PAGES
776	bool "64KB"
777	help
778	  This feature enables 64KB pages support (4KB by default)
779	  allowing only two levels of page tables and faster TLB
780	  look-up. AArch32 emulation requires applications compiled
781	  with 64K aligned segments.
782
783endchoice
784
785choice
786	prompt "Virtual address space size"
787	default ARM64_VA_BITS_39 if ARM64_4K_PAGES
788	default ARM64_VA_BITS_47 if ARM64_16K_PAGES
789	default ARM64_VA_BITS_42 if ARM64_64K_PAGES
790	help
791	  Allows choosing one of multiple possible virtual address
792	  space sizes. The level of translation table is determined by
793	  a combination of page size and virtual address space size.
794
795config ARM64_VA_BITS_36
796	bool "36-bit" if EXPERT
797	depends on ARM64_16K_PAGES
798
799config ARM64_VA_BITS_39
800	bool "39-bit"
801	depends on ARM64_4K_PAGES
802
803config ARM64_VA_BITS_42
804	bool "42-bit"
805	depends on ARM64_64K_PAGES
806
807config ARM64_VA_BITS_47
808	bool "47-bit"
809	depends on ARM64_16K_PAGES
810
811config ARM64_VA_BITS_48
812	bool "48-bit"
813
814config ARM64_VA_BITS_52
815	bool "52-bit"
816	depends on ARM64_64K_PAGES && (ARM64_PAN || !ARM64_SW_TTBR0_PAN)
817	help
818	  Enable 52-bit virtual addressing for userspace when explicitly
819	  requested via a hint to mmap(). The kernel will also use 52-bit
820	  virtual addresses for its own mappings (provided HW support for
821	  this feature is available, otherwise it reverts to 48-bit).
822
823	  NOTE: Enabling 52-bit virtual addressing in conjunction with
824	  ARMv8.3 Pointer Authentication will result in the PAC being
825	  reduced from 7 bits to 3 bits, which may have a significant
826	  impact on its susceptibility to brute-force attacks.
827
828	  If unsure, select 48-bit virtual addressing instead.
829
830endchoice
831
832config ARM64_FORCE_52BIT
833	bool "Force 52-bit virtual addresses for userspace"
834	depends on ARM64_VA_BITS_52 && EXPERT
835	help
836	  For systems with 52-bit userspace VAs enabled, the kernel will attempt
837	  to maintain compatibility with older software by providing 48-bit VAs
838	  unless a hint is supplied to mmap.
839
840	  This configuration option disables the 48-bit compatibility logic, and
841	  forces all userspace addresses to be 52-bit on HW that supports it. One
842	  should only enable this configuration option for stress testing userspace
843	  memory management code. If unsure say N here.
844
845config ARM64_VA_BITS
846	int
847	default 36 if ARM64_VA_BITS_36
848	default 39 if ARM64_VA_BITS_39
849	default 42 if ARM64_VA_BITS_42
850	default 47 if ARM64_VA_BITS_47
851	default 48 if ARM64_VA_BITS_48
852	default 52 if ARM64_VA_BITS_52
853
854choice
855	prompt "Physical address space size"
856	default ARM64_PA_BITS_48
857	help
858	  Choose the maximum physical address range that the kernel will
859	  support.
860
861config ARM64_PA_BITS_48
862	bool "48-bit"
863
864config ARM64_PA_BITS_52
865	bool "52-bit (ARMv8.2)"
866	depends on ARM64_64K_PAGES
867	depends on ARM64_PAN || !ARM64_SW_TTBR0_PAN
868	help
869	  Enable support for a 52-bit physical address space, introduced as
870	  part of the ARMv8.2-LPA extension.
871
872	  With this enabled, the kernel will also continue to work on CPUs that
873	  do not support ARMv8.2-LPA, but with some added memory overhead (and
874	  minor performance overhead).
875
876endchoice
877
878config ARM64_PA_BITS
879	int
880	default 48 if ARM64_PA_BITS_48
881	default 52 if ARM64_PA_BITS_52
882
883config CPU_BIG_ENDIAN
884       bool "Build big-endian kernel"
885       help
886         Say Y if you plan on running a kernel in big-endian mode.
887
888config SCHED_MC
889	bool "Multi-core scheduler support"
890	help
891	  Multi-core scheduler support improves the CPU scheduler's decision
892	  making when dealing with multi-core CPU chips at a cost of slightly
893	  increased overhead in some places. If unsure say N here.
894
895config SCHED_SMT
896	bool "SMT scheduler support"
897	help
898	  Improves the CPU scheduler's decision making when dealing with
899	  MultiThreading at a cost of slightly increased overhead in some
900	  places. If unsure say N here.
901
902config NR_CPUS
903	int "Maximum number of CPUs (2-4096)"
904	range 2 4096
905	default "256"
906
907config HOTPLUG_CPU
908	bool "Support for hot-pluggable CPUs"
909	select GENERIC_IRQ_MIGRATION
910	help
911	  Say Y here to experiment with turning CPUs off and on.  CPUs
912	  can be controlled through /sys/devices/system/cpu.
913
914# Common NUMA Features
915config NUMA
916	bool "Numa Memory Allocation and Scheduler Support"
917	select ACPI_NUMA if ACPI
918	select OF_NUMA
919	help
920	  Enable NUMA (Non Uniform Memory Access) support.
921
922	  The kernel will try to allocate memory used by a CPU on the
923	  local memory of the CPU and add some more
924	  NUMA awareness to the kernel.
925
926config NODES_SHIFT
927	int "Maximum NUMA Nodes (as a power of 2)"
928	range 1 10
929	default "2"
930	depends on NEED_MULTIPLE_NODES
931	help
932	  Specify the maximum number of NUMA Nodes available on the target
933	  system.  Increases memory reserved to accommodate various tables.
934
935config USE_PERCPU_NUMA_NODE_ID
936	def_bool y
937	depends on NUMA
938
939config HAVE_SETUP_PER_CPU_AREA
940	def_bool y
941	depends on NUMA
942
943config NEED_PER_CPU_EMBED_FIRST_CHUNK
944	def_bool y
945	depends on NUMA
946
947config HOLES_IN_ZONE
948	def_bool y
949
950source "kernel/Kconfig.hz"
951
952config ARCH_SUPPORTS_DEBUG_PAGEALLOC
953	def_bool y
954
955config ARCH_SPARSEMEM_ENABLE
956	def_bool y
957	select SPARSEMEM_VMEMMAP_ENABLE
958
959config ARCH_SPARSEMEM_DEFAULT
960	def_bool ARCH_SPARSEMEM_ENABLE
961
962config ARCH_SELECT_MEMORY_MODEL
963	def_bool ARCH_SPARSEMEM_ENABLE
964
965config ARCH_FLATMEM_ENABLE
966	def_bool !NUMA
967
968config HAVE_ARCH_PFN_VALID
969	def_bool y
970
971config HW_PERF_EVENTS
972	def_bool y
973	depends on ARM_PMU
974
975config SYS_SUPPORTS_HUGETLBFS
976	def_bool y
977
978config ARCH_WANT_HUGE_PMD_SHARE
979
980config ARCH_HAS_CACHE_LINE_SIZE
981	def_bool y
982
983config ARCH_ENABLE_SPLIT_PMD_PTLOCK
984	def_bool y if PGTABLE_LEVELS > 2
985
986# Supported by clang >= 7.0
987config CC_HAVE_SHADOW_CALL_STACK
988	def_bool $(cc-option, -fsanitize=shadow-call-stack -ffixed-x18)
989
990config SECCOMP
991	bool "Enable seccomp to safely compute untrusted bytecode"
992	---help---
993	  This kernel feature is useful for number crunching applications
994	  that may need to compute untrusted bytecode during their
995	  execution. By using pipes or other transports made available to
996	  the process as file descriptors supporting the read/write
997	  syscalls, it's possible to isolate those applications in
998	  their own address space using seccomp. Once seccomp is
999	  enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
1000	  and the task is only allowed to execute a few safe syscalls
1001	  defined by each seccomp mode.
1002
1003config PARAVIRT
1004	bool "Enable paravirtualization code"
1005	help
1006	  This changes the kernel so it can modify itself when it is run
1007	  under a hypervisor, potentially improving performance significantly
1008	  over full virtualization.
1009
1010config PARAVIRT_TIME_ACCOUNTING
1011	bool "Paravirtual steal time accounting"
1012	select PARAVIRT
1013	help
1014	  Select this option to enable fine granularity task steal time
1015	  accounting. Time spent executing other tasks in parallel with
1016	  the current vCPU is discounted from the vCPU power. To account for
1017	  that, there can be a small performance impact.
1018
1019	  If in doubt, say N here.
1020
1021config KEXEC
1022	depends on PM_SLEEP_SMP
1023	select KEXEC_CORE
1024	bool "kexec system call"
1025	---help---
1026	  kexec is a system call that implements the ability to shutdown your
1027	  current kernel, and to start another kernel.  It is like a reboot
1028	  but it is independent of the system firmware.   And like a reboot
1029	  you can start any kernel with it, not just Linux.
1030
1031config KEXEC_FILE
1032	bool "kexec file based system call"
1033	select KEXEC_CORE
1034	help
1035	  This is new version of kexec system call. This system call is
1036	  file based and takes file descriptors as system call argument
1037	  for kernel and initramfs as opposed to list of segments as
1038	  accepted by previous system call.
1039
1040config KEXEC_SIG
1041	bool "Verify kernel signature during kexec_file_load() syscall"
1042	depends on KEXEC_FILE
1043	help
1044	  Select this option to verify a signature with loaded kernel
1045	  image. If configured, any attempt of loading a image without
1046	  valid signature will fail.
1047
1048	  In addition to that option, you need to enable signature
1049	  verification for the corresponding kernel image type being
1050	  loaded in order for this to work.
1051
1052config KEXEC_IMAGE_VERIFY_SIG
1053	bool "Enable Image signature verification support"
1054	default y
1055	depends on KEXEC_SIG
1056	depends on EFI && SIGNED_PE_FILE_VERIFICATION
1057	help
1058	  Enable Image signature verification support.
1059
1060comment "Support for PE file signature verification disabled"
1061	depends on KEXEC_SIG
1062	depends on !EFI || !SIGNED_PE_FILE_VERIFICATION
1063
1064config CRASH_DUMP
1065	bool "Build kdump crash kernel"
1066	help
1067	  Generate crash dump after being started by kexec. This should
1068	  be normally only set in special crash dump kernels which are
1069	  loaded in the main kernel with kexec-tools into a specially
1070	  reserved region and then later executed after a crash by
1071	  kdump/kexec.
1072
1073	  For more details see Documentation/admin-guide/kdump/kdump.rst
1074
1075config XEN_DOM0
1076	def_bool y
1077	depends on XEN
1078
1079config XEN
1080	bool "Xen guest support on ARM64"
1081	depends on ARM64 && OF
1082	select SWIOTLB_XEN
1083	select PARAVIRT
1084	help
1085	  Say Y if you want to run Linux in a Virtual Machine on Xen on ARM64.
1086
1087config FORCE_MAX_ZONEORDER
1088	int
1089	default "14" if (ARM64_64K_PAGES && TRANSPARENT_HUGEPAGE)
1090	default "12" if (ARM64_16K_PAGES && TRANSPARENT_HUGEPAGE)
1091	default "11"
1092	help
1093	  The kernel memory allocator divides physically contiguous memory
1094	  blocks into "zones", where each zone is a power of two number of
1095	  pages.  This option selects the largest power of two that the kernel
1096	  keeps in the memory allocator.  If you need to allocate very large
1097	  blocks of physically contiguous memory, then you may need to
1098	  increase this value.
1099
1100	  This config option is actually maximum order plus one. For example,
1101	  a value of 11 means that the largest free memory block is 2^10 pages.
1102
1103	  We make sure that we can allocate upto a HugePage size for each configuration.
1104	  Hence we have :
1105		MAX_ORDER = (PMD_SHIFT - PAGE_SHIFT) + 1 => PAGE_SHIFT - 2
1106
1107	  However for 4K, we choose a higher default value, 11 as opposed to 10, giving us
1108	  4M allocations matching the default size used by generic code.
1109
1110config UNMAP_KERNEL_AT_EL0
1111	bool "Unmap kernel when running in userspace (aka \"KAISER\")" if EXPERT
1112	default y
1113	help
1114	  Speculation attacks against some high-performance processors can
1115	  be used to bypass MMU permission checks and leak kernel data to
1116	  userspace. This can be defended against by unmapping the kernel
1117	  when running in userspace, mapping it back in on exception entry
1118	  via a trampoline page in the vector table.
1119
1120	  If unsure, say Y.
1121
1122config HARDEN_BRANCH_PREDICTOR
1123	bool "Harden the branch predictor against aliasing attacks" if EXPERT
1124	default y
1125	help
1126	  Speculation attacks against some high-performance processors rely on
1127	  being able to manipulate the branch predictor for a victim context by
1128	  executing aliasing branches in the attacker context.  Such attacks
1129	  can be partially mitigated against by clearing internal branch
1130	  predictor state and limiting the prediction logic in some situations.
1131
1132	  This config option will take CPU-specific actions to harden the
1133	  branch predictor against aliasing attacks and may rely on specific
1134	  instruction sequences or control bits being set by the system
1135	  firmware.
1136
1137	  If unsure, say Y.
1138
1139config HARDEN_EL2_VECTORS
1140	bool "Harden EL2 vector mapping against system register leak" if EXPERT
1141	default y
1142	help
1143	  Speculation attacks against some high-performance processors can
1144	  be used to leak privileged information such as the vector base
1145	  register, resulting in a potential defeat of the EL2 layout
1146	  randomization.
1147
1148	  This config option will map the vectors to a fixed location,
1149	  independent of the EL2 code mapping, so that revealing VBAR_EL2
1150	  to an attacker does not give away any extra information. This
1151	  only gets enabled on affected CPUs.
1152
1153	  If unsure, say Y.
1154
1155config ARM64_SSBD
1156	bool "Speculative Store Bypass Disable" if EXPERT
1157	default y
1158	help
1159	  This enables mitigation of the bypassing of previous stores
1160	  by speculative loads.
1161
1162	  If unsure, say Y.
1163
1164config MITIGATE_SPECTRE_BRANCH_HISTORY
1165	bool "Mitigate Spectre style attacks against branch history" if EXPERT
1166	default y
1167	help
1168	  Speculation attacks against some high-performance processors can
1169	  make use of branch history to influence future speculation.
1170	  When taking an exception from user-space, a sequence of branches
1171	  or a firmware call overwrites the branch history.
1172
1173config RODATA_FULL_DEFAULT_ENABLED
1174	bool "Apply r/o permissions of VM areas also to their linear aliases"
1175	default y
1176	help
1177	  Apply read-only attributes of VM areas to the linear alias of
1178	  the backing pages as well. This prevents code or read-only data
1179	  from being modified (inadvertently or intentionally) via another
1180	  mapping of the same memory page. This additional enhancement can
1181	  be turned off at runtime by passing rodata=[off|on] (and turned on
1182	  with rodata=full if this option is set to 'n')
1183
1184	  This requires the linear region to be mapped down to pages,
1185	  which may adversely affect performance in some cases.
1186
1187config ARM64_SW_TTBR0_PAN
1188	bool "Emulate Privileged Access Never using TTBR0_EL1 switching"
1189	help
1190	  Enabling this option prevents the kernel from accessing
1191	  user-space memory directly by pointing TTBR0_EL1 to a reserved
1192	  zeroed area and reserved ASID. The user access routines
1193	  restore the valid TTBR0_EL1 temporarily.
1194
1195config ARM64_TAGGED_ADDR_ABI
1196	bool "Enable the tagged user addresses syscall ABI"
1197	default y
1198	help
1199	  When this option is enabled, user applications can opt in to a
1200	  relaxed ABI via prctl() allowing tagged addresses to be passed
1201	  to system calls as pointer arguments. For details, see
1202	  Documentation/arm64/tagged-address-abi.rst.
1203
1204menuconfig COMPAT
1205	bool "Kernel support for 32-bit EL0"
1206	depends on ARM64_4K_PAGES || EXPERT
1207	select COMPAT_BINFMT_ELF if BINFMT_ELF
1208	select HAVE_UID16
1209	select OLD_SIGSUSPEND3
1210	select COMPAT_OLD_SIGACTION
1211	help
1212	  This option enables support for a 32-bit EL0 running under a 64-bit
1213	  kernel at EL1. AArch32-specific components such as system calls,
1214	  the user helper functions, VFP support and the ptrace interface are
1215	  handled appropriately by the kernel.
1216
1217	  If you use a page size other than 4KB (i.e, 16KB or 64KB), please be aware
1218	  that you will only be able to execute AArch32 binaries that were compiled
1219	  with page size aligned segments.
1220
1221	  If you want to execute 32-bit userspace applications, say Y.
1222
1223if COMPAT
1224
1225config KUSER_HELPERS
1226	bool "Enable kuser helpers page for 32-bit applications"
1227	default y
1228	help
1229	  Warning: disabling this option may break 32-bit user programs.
1230
1231	  Provide kuser helpers to compat tasks. The kernel provides
1232	  helper code to userspace in read only form at a fixed location
1233	  to allow userspace to be independent of the CPU type fitted to
1234	  the system. This permits binaries to be run on ARMv4 through
1235	  to ARMv8 without modification.
1236
1237	  See Documentation/arm/kernel_user_helpers.rst for details.
1238
1239	  However, the fixed address nature of these helpers can be used
1240	  by ROP (return orientated programming) authors when creating
1241	  exploits.
1242
1243	  If all of the binaries and libraries which run on your platform
1244	  are built specifically for your platform, and make no use of
1245	  these helpers, then you can turn this option off to hinder
1246	  such exploits. However, in that case, if a binary or library
1247	  relying on those helpers is run, it will not function correctly.
1248
1249	  Say N here only if you are absolutely certain that you do not
1250	  need these helpers; otherwise, the safe option is to say Y.
1251
1252config COMPAT_VDSO
1253	bool "Enable vDSO for 32-bit applications"
1254	depends on !CPU_BIG_ENDIAN && "$(CROSS_COMPILE_COMPAT)" != ""
1255	select GENERIC_COMPAT_VDSO
1256	default y
1257	help
1258	  Place in the process address space of 32-bit applications an
1259	  ELF shared object providing fast implementations of gettimeofday
1260	  and clock_gettime.
1261
1262	  You must have a 32-bit build of glibc 2.22 or later for programs
1263	  to seamlessly take advantage of this.
1264
1265menuconfig ARMV8_DEPRECATED
1266	bool "Emulate deprecated/obsolete ARMv8 instructions"
1267	depends on SYSCTL
1268	help
1269	  Legacy software support may require certain instructions
1270	  that have been deprecated or obsoleted in the architecture.
1271
1272	  Enable this config to enable selective emulation of these
1273	  features.
1274
1275	  If unsure, say Y
1276
1277if ARMV8_DEPRECATED
1278
1279config SWP_EMULATION
1280	bool "Emulate SWP/SWPB instructions"
1281	help
1282	  ARMv8 obsoletes the use of A32 SWP/SWPB instructions such that
1283	  they are always undefined. Say Y here to enable software
1284	  emulation of these instructions for userspace using LDXR/STXR.
1285
1286	  In some older versions of glibc [<=2.8] SWP is used during futex
1287	  trylock() operations with the assumption that the code will not
1288	  be preempted. This invalid assumption may be more likely to fail
1289	  with SWP emulation enabled, leading to deadlock of the user
1290	  application.
1291
1292	  NOTE: when accessing uncached shared regions, LDXR/STXR rely
1293	  on an external transaction monitoring block called a global
1294	  monitor to maintain update atomicity. If your system does not
1295	  implement a global monitor, this option can cause programs that
1296	  perform SWP operations to uncached memory to deadlock.
1297
1298	  If unsure, say Y
1299
1300config CP15_BARRIER_EMULATION
1301	bool "Emulate CP15 Barrier instructions"
1302	help
1303	  The CP15 barrier instructions - CP15ISB, CP15DSB, and
1304	  CP15DMB - are deprecated in ARMv8 (and ARMv7). It is
1305	  strongly recommended to use the ISB, DSB, and DMB
1306	  instructions instead.
1307
1308	  Say Y here to enable software emulation of these
1309	  instructions for AArch32 userspace code. When this option is
1310	  enabled, CP15 barrier usage is traced which can help
1311	  identify software that needs updating.
1312
1313	  If unsure, say Y
1314
1315config SETEND_EMULATION
1316	bool "Emulate SETEND instruction"
1317	help
1318	  The SETEND instruction alters the data-endianness of the
1319	  AArch32 EL0, and is deprecated in ARMv8.
1320
1321	  Say Y here to enable software emulation of the instruction
1322	  for AArch32 userspace code.
1323
1324	  Note: All the cpus on the system must have mixed endian support at EL0
1325	  for this feature to be enabled. If a new CPU - which doesn't support mixed
1326	  endian - is hotplugged in after this feature has been enabled, there could
1327	  be unexpected results in the applications.
1328
1329	  If unsure, say Y
1330endif
1331
1332endif
1333
1334menu "ARMv8.1 architectural features"
1335
1336config ARM64_HW_AFDBM
1337	bool "Support for hardware updates of the Access and Dirty page flags"
1338	default y
1339	help
1340	  The ARMv8.1 architecture extensions introduce support for
1341	  hardware updates of the access and dirty information in page
1342	  table entries. When enabled in TCR_EL1 (HA and HD bits) on
1343	  capable processors, accesses to pages with PTE_AF cleared will
1344	  set this bit instead of raising an access flag fault.
1345	  Similarly, writes to read-only pages with the DBM bit set will
1346	  clear the read-only bit (AP[2]) instead of raising a
1347	  permission fault.
1348
1349	  Kernels built with this configuration option enabled continue
1350	  to work on pre-ARMv8.1 hardware and the performance impact is
1351	  minimal. If unsure, say Y.
1352
1353config ARM64_PAN
1354	bool "Enable support for Privileged Access Never (PAN)"
1355	default y
1356	help
1357	 Privileged Access Never (PAN; part of the ARMv8.1 Extensions)
1358	 prevents the kernel or hypervisor from accessing user-space (EL0)
1359	 memory directly.
1360
1361	 Choosing this option will cause any unprotected (not using
1362	 copy_to_user et al) memory access to fail with a permission fault.
1363
1364	 The feature is detected at runtime, and will remain as a 'nop'
1365	 instruction if the cpu does not implement the feature.
1366
1367config ARM64_LSE_ATOMICS
1368	bool "Atomic instructions"
1369	depends on JUMP_LABEL
1370	default y
1371	help
1372	  As part of the Large System Extensions, ARMv8.1 introduces new
1373	  atomic instructions that are designed specifically to scale in
1374	  very large systems.
1375
1376	  Say Y here to make use of these instructions for the in-kernel
1377	  atomic routines. This incurs a small overhead on CPUs that do
1378	  not support these instructions and requires the kernel to be
1379	  built with binutils >= 2.25 in order for the new instructions
1380	  to be used.
1381
1382config ARM64_VHE
1383	bool "Enable support for Virtualization Host Extensions (VHE)"
1384	default y
1385	help
1386	  Virtualization Host Extensions (VHE) allow the kernel to run
1387	  directly at EL2 (instead of EL1) on processors that support
1388	  it. This leads to better performance for KVM, as they reduce
1389	  the cost of the world switch.
1390
1391	  Selecting this option allows the VHE feature to be detected
1392	  at runtime, and does not affect processors that do not
1393	  implement this feature.
1394
1395endmenu
1396
1397menu "ARMv8.2 architectural features"
1398
1399config ARM64_UAO
1400	bool "Enable support for User Access Override (UAO)"
1401	default y
1402	help
1403	  User Access Override (UAO; part of the ARMv8.2 Extensions)
1404	  causes the 'unprivileged' variant of the load/store instructions to
1405	  be overridden to be privileged.
1406
1407	  This option changes get_user() and friends to use the 'unprivileged'
1408	  variant of the load/store instructions. This ensures that user-space
1409	  really did have access to the supplied memory. When addr_limit is
1410	  set to kernel memory the UAO bit will be set, allowing privileged
1411	  access to kernel memory.
1412
1413	  Choosing this option will cause copy_to_user() et al to use user-space
1414	  memory permissions.
1415
1416	  The feature is detected at runtime, the kernel will use the
1417	  regular load/store instructions if the cpu does not implement the
1418	  feature.
1419
1420config ARM64_PMEM
1421	bool "Enable support for persistent memory"
1422	select ARCH_HAS_PMEM_API
1423	select ARCH_HAS_UACCESS_FLUSHCACHE
1424	help
1425	  Say Y to enable support for the persistent memory API based on the
1426	  ARMv8.2 DCPoP feature.
1427
1428	  The feature is detected at runtime, and the kernel will use DC CVAC
1429	  operations if DC CVAP is not supported (following the behaviour of
1430	  DC CVAP itself if the system does not define a point of persistence).
1431
1432config ARM64_RAS_EXTN
1433	bool "Enable support for RAS CPU Extensions"
1434	default y
1435	help
1436	  CPUs that support the Reliability, Availability and Serviceability
1437	  (RAS) Extensions, part of ARMv8.2 are able to track faults and
1438	  errors, classify them and report them to software.
1439
1440	  On CPUs with these extensions system software can use additional
1441	  barriers to determine if faults are pending and read the
1442	  classification from a new set of registers.
1443
1444	  Selecting this feature will allow the kernel to use these barriers
1445	  and access the new registers if the system supports the extension.
1446	  Platform RAS features may additionally depend on firmware support.
1447
1448config ARM64_CNP
1449	bool "Enable support for Common Not Private (CNP) translations"
1450	default y
1451	depends on ARM64_PAN || !ARM64_SW_TTBR0_PAN
1452	help
1453	  Common Not Private (CNP) allows translation table entries to
1454	  be shared between different PEs in the same inner shareable
1455	  domain, so the hardware can use this fact to optimise the
1456	  caching of such entries in the TLB.
1457
1458	  Selecting this option allows the CNP feature to be detected
1459	  at runtime, and does not affect PEs that do not implement
1460	  this feature.
1461
1462endmenu
1463
1464menu "ARMv8.3 architectural features"
1465
1466config ARM64_PTR_AUTH
1467	bool "Enable support for pointer authentication"
1468	default y
1469	depends on !KVM || ARM64_VHE
1470	help
1471	  Pointer authentication (part of the ARMv8.3 Extensions) provides
1472	  instructions for signing and authenticating pointers against secret
1473	  keys, which can be used to mitigate Return Oriented Programming (ROP)
1474	  and other attacks.
1475
1476	  This option enables these instructions at EL0 (i.e. for userspace).
1477
1478	  Choosing this option will cause the kernel to initialise secret keys
1479	  for each process at exec() time, with these keys being
1480	  context-switched along with the process.
1481
1482	  The feature is detected at runtime. If the feature is not present in
1483	  hardware it will not be advertised to userspace/KVM guest nor will it
1484	  be enabled. However, KVM guest also require VHE mode and hence
1485	  CONFIG_ARM64_VHE=y option to use this feature.
1486
1487endmenu
1488
1489menu "ARMv8.4 architectural features"
1490
1491config ARM64_AMU_EXTN
1492	bool "Enable support for the Activity Monitors Unit CPU extension"
1493	default y
1494	help
1495	  The activity monitors extension is an optional extension introduced
1496	  by the ARMv8.4 CPU architecture. This enables support for version 1
1497	  of the activity monitors architecture, AMUv1.
1498
1499	  To enable the use of this extension on CPUs that implement it, say Y.
1500
1501	  Note that for architectural reasons, firmware _must_ implement AMU
1502	  support when running on CPUs that present the activity monitors
1503	  extension. The required support is present in:
1504	    * Version 1.5 and later of the ARM Trusted Firmware
1505
1506	  For kernels that have this configuration enabled but boot with broken
1507	  firmware, you may need to say N here until the firmware is fixed.
1508	  Otherwise you may experience firmware panics or lockups when
1509	  accessing the counter registers. Even if you are not observing these
1510	  symptoms, the values returned by the register reads might not
1511	  correctly reflect reality. Most commonly, the value read will be 0,
1512	  indicating that the counter is not enabled.
1513
1514endmenu
1515
1516config ARM64_SVE
1517	bool "ARM Scalable Vector Extension support"
1518	default y
1519	depends on !KVM || ARM64_VHE
1520	help
1521	  The Scalable Vector Extension (SVE) is an extension to the AArch64
1522	  execution state which complements and extends the SIMD functionality
1523	  of the base architecture to support much larger vectors and to enable
1524	  additional vectorisation opportunities.
1525
1526	  To enable use of this extension on CPUs that implement it, say Y.
1527
1528	  On CPUs that support the SVE2 extensions, this option will enable
1529	  those too.
1530
1531	  Note that for architectural reasons, firmware _must_ implement SVE
1532	  support when running on SVE capable hardware.  The required support
1533	  is present in:
1534
1535	    * version 1.5 and later of the ARM Trusted Firmware
1536	    * the AArch64 boot wrapper since commit 5e1261e08abf
1537	      ("bootwrapper: SVE: Enable SVE for EL2 and below").
1538
1539	  For other firmware implementations, consult the firmware documentation
1540	  or vendor.
1541
1542	  If you need the kernel to boot on SVE-capable hardware with broken
1543	  firmware, you may need to say N here until you get your firmware
1544	  fixed.  Otherwise, you may experience firmware panics or lockups when
1545	  booting the kernel.  If unsure and you are not observing these
1546	  symptoms, you should assume that it is safe to say Y.
1547
1548	  CPUs that support SVE are architecturally required to support the
1549	  Virtualization Host Extensions (VHE), so the kernel makes no
1550	  provision for supporting SVE alongside KVM without VHE enabled.
1551	  Thus, you will need to enable CONFIG_ARM64_VHE if you want to support
1552	  KVM in the same kernel image.
1553
1554config ARM64_MODULE_PLTS
1555	bool "Use PLTs to allow module memory to spill over into vmalloc area"
1556	depends on MODULES
1557	select HAVE_MOD_ARCH_SPECIFIC
1558	help
1559	  Allocate PLTs when loading modules so that jumps and calls whose
1560	  targets are too far away for their relative offsets to be encoded
1561	  in the instructions themselves can be bounced via veneers in the
1562	  module's PLT. This allows modules to be allocated in the generic
1563	  vmalloc area after the dedicated module memory area has been
1564	  exhausted.
1565
1566	  When running with address space randomization (KASLR), the module
1567	  region itself may be too far away for ordinary relative jumps and
1568	  calls, and so in that case, module PLTs are required and cannot be
1569	  disabled.
1570
1571	  Specific errata workaround(s) might also force module PLTs to be
1572	  enabled (ARM64_ERRATUM_843419).
1573
1574config ARM64_PSEUDO_NMI
1575	bool "Support for NMI-like interrupts"
1576	select CONFIG_ARM_GIC_V3
1577	help
1578	  Adds support for mimicking Non-Maskable Interrupts through the use of
1579	  GIC interrupt priority. This support requires version 3 or later of
1580	  ARM GIC.
1581
1582	  This high priority configuration for interrupts needs to be
1583	  explicitly enabled by setting the kernel parameter
1584	  "irqchip.gicv3_pseudo_nmi" to 1.
1585
1586	  If unsure, say N
1587
1588if ARM64_PSEUDO_NMI
1589config ARM64_DEBUG_PRIORITY_MASKING
1590	bool "Debug interrupt priority masking"
1591	help
1592	  This adds runtime checks to functions enabling/disabling
1593	  interrupts when using priority masking. The additional checks verify
1594	  the validity of ICC_PMR_EL1 when calling concerned functions.
1595
1596	  If unsure, say N
1597endif
1598
1599config RELOCATABLE
1600	bool
1601	select ARCH_HAS_RELR
1602	help
1603	  This builds the kernel as a Position Independent Executable (PIE),
1604	  which retains all relocation metadata required to relocate the
1605	  kernel binary at runtime to a different virtual address than the
1606	  address it was linked at.
1607	  Since AArch64 uses the RELA relocation format, this requires a
1608	  relocation pass at runtime even if the kernel is loaded at the
1609	  same address it was linked at.
1610
1611config RANDOMIZE_BASE
1612	bool "Randomize the address of the kernel image"
1613	select ARM64_MODULE_PLTS if MODULES
1614	select RELOCATABLE
1615	help
1616	  Randomizes the virtual address at which the kernel image is
1617	  loaded, as a security feature that deters exploit attempts
1618	  relying on knowledge of the location of kernel internals.
1619
1620	  It is the bootloader's job to provide entropy, by passing a
1621	  random u64 value in /chosen/kaslr-seed at kernel entry.
1622
1623	  When booting via the UEFI stub, it will invoke the firmware's
1624	  EFI_RNG_PROTOCOL implementation (if available) to supply entropy
1625	  to the kernel proper. In addition, it will randomise the physical
1626	  location of the kernel Image as well.
1627
1628	  If unsure, say N.
1629
1630config RANDOMIZE_MODULE_REGION_FULL
1631	bool "Randomize the module region over a 4 GB range"
1632	depends on RANDOMIZE_BASE
1633	default y
1634	help
1635	  Randomizes the location of the module region inside a 4 GB window
1636	  covering the core kernel. This way, it is less likely for modules
1637	  to leak information about the location of core kernel data structures
1638	  but it does imply that function calls between modules and the core
1639	  kernel will need to be resolved via veneers in the module PLT.
1640
1641	  When this option is not set, the module region will be randomized over
1642	  a limited range that contains the [_stext, _etext] interval of the
1643	  core kernel, so branch relocations are always in range.
1644
1645config CC_HAVE_STACKPROTECTOR_SYSREG
1646	def_bool $(cc-option,-mstack-protector-guard=sysreg -mstack-protector-guard-reg=sp_el0 -mstack-protector-guard-offset=0)
1647
1648config STACKPROTECTOR_PER_TASK
1649	def_bool y
1650	depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_SYSREG
1651
1652endmenu
1653
1654menu "Boot options"
1655
1656config ARM64_ACPI_PARKING_PROTOCOL
1657	bool "Enable support for the ARM64 ACPI parking protocol"
1658	depends on ACPI
1659	help
1660	  Enable support for the ARM64 ACPI parking protocol. If disabled
1661	  the kernel will not allow booting through the ARM64 ACPI parking
1662	  protocol even if the corresponding data is present in the ACPI
1663	  MADT table.
1664
1665config CMDLINE
1666	string "Default kernel command string"
1667	default ""
1668	help
1669	  Provide a set of default command-line options at build time by
1670	  entering them here. As a minimum, you should specify the the
1671	  root device (e.g. root=/dev/nfs).
1672
1673choice
1674	prompt "Kernel command line type" if CMDLINE != ""
1675	default CMDLINE_FROM_BOOTLOADER
1676
1677config CMDLINE_FROM_BOOTLOADER
1678	bool "Use bootloader kernel arguments if available"
1679	help
1680	  Uses the command-line options passed by the boot loader. If
1681	  the boot loader doesn't provide any, the default kernel command
1682	  string provided in CMDLINE will be used.
1683
1684config CMDLINE_EXTEND
1685	bool "Extend bootloader kernel arguments"
1686	help
1687	  The command-line arguments provided by the boot loader will be
1688	  appended to the default kernel command string.
1689
1690config CMDLINE_FORCE
1691	bool "Always use the default kernel command string"
1692	help
1693	  Always use the default kernel command string, even if the boot
1694	  loader passes other arguments to the kernel.
1695	  This is useful if you cannot or don't want to change the
1696	  command-line options your boot loader passes to the kernel.
1697endchoice
1698
1699config EFI_STUB
1700	bool
1701
1702config EFI
1703	bool "UEFI runtime support"
1704	depends on OF && !CPU_BIG_ENDIAN
1705	depends on KERNEL_MODE_NEON
1706	select ARCH_SUPPORTS_ACPI
1707	select LIBFDT
1708	select UCS2_STRING
1709	select EFI_PARAMS_FROM_FDT
1710	select EFI_RUNTIME_WRAPPERS
1711	select EFI_STUB
1712	select EFI_ARMSTUB
1713	default y
1714	help
1715	  This option provides support for runtime services provided
1716	  by UEFI firmware (such as non-volatile variables, realtime
1717          clock, and platform reset). A UEFI stub is also provided to
1718	  allow the kernel to be booted as an EFI application. This
1719	  is only useful on systems that have UEFI firmware.
1720
1721config DMI
1722	bool "Enable support for SMBIOS (DMI) tables"
1723	depends on EFI
1724	default y
1725	help
1726	  This enables SMBIOS/DMI feature for systems.
1727
1728	  This option is only useful on systems that have UEFI firmware.
1729	  However, even with this option, the resultant kernel should
1730	  continue to boot on existing non-UEFI platforms.
1731
1732endmenu
1733
1734config SYSVIPC_COMPAT
1735	def_bool y
1736	depends on COMPAT && SYSVIPC
1737
1738config ARCH_ENABLE_HUGEPAGE_MIGRATION
1739	def_bool y
1740	depends on HUGETLB_PAGE && MIGRATION
1741
1742menu "Power management options"
1743
1744source "kernel/power/Kconfig"
1745
1746config ARCH_HIBERNATION_POSSIBLE
1747	def_bool y
1748	depends on CPU_PM
1749
1750config ARCH_HIBERNATION_HEADER
1751	def_bool y
1752	depends on HIBERNATION
1753
1754config ARCH_SUSPEND_POSSIBLE
1755	def_bool y
1756
1757endmenu
1758
1759menu "CPU Power Management"
1760
1761source "drivers/cpuidle/Kconfig"
1762
1763source "drivers/cpufreq/Kconfig"
1764
1765endmenu
1766
1767source "drivers/firmware/Kconfig"
1768
1769source "drivers/acpi/Kconfig"
1770
1771source "arch/arm64/kvm/Kconfig"
1772
1773if CRYPTO
1774source "arch/arm64/crypto/Kconfig"
1775endif
1776