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 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_PER_VMA_LOCK 85 select ARCH_SUPPORTS_HUGE_PFNMAP if TRANSPARENT_HUGEPAGE 86 select ARCH_SUPPORTS_RMM 87 select ARCH_SUPPORTS_RT 88 select ARCH_SUPPORTS_SCHED_SMT 89 select ARCH_SUPPORTS_SCHED_CLUSTER 90 select ARCH_SUPPORTS_SCHED_MC 91 select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH 92 select ARCH_WANT_COMPAT_IPC_PARSE_VERSION if COMPAT 93 select ARCH_WANT_DEFAULT_BPF_JIT 94 select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT 95 select ARCH_WANT_FRAME_POINTERS 96 select ARCH_WANT_HUGE_PMD_SHARE if ARM64_4K_PAGES || (ARM64_16K_PAGES && !ARM64_VA_BITS_36) 97 select ARCH_WANT_LD_ORPHAN_WARN 98 select ARCH_WANTS_EXECMEM_LATE 99 select ARCH_WANTS_NO_INSTR 100 select ARCH_WANTS_THP_SWAP if ARM64_4K_PAGES 101 select ARCH_HAS_UBSAN 102 select ARM_AMBA 103 select ARM_ARCH_TIMER 104 select ARM_GIC 105 select AUDIT_ARCH_COMPAT_GENERIC 106 select ARM_GIC_V2M if PCI 107 select ARM_GIC_V3 108 select ARM_GIC_V3_ITS if PCI 109 select ARM_GIC_V5 110 select ARM_PSCI_FW 111 select BUILDTIME_TABLE_SORT 112 select CLONE_BACKWARDS 113 select COMMON_CLK 114 select CPU_PM if (SUSPEND || CPU_IDLE) 115 select CPUMASK_OFFSTACK if NR_CPUS > 256 116 select DCACHE_WORD_ACCESS 117 select HAVE_EXTRA_IPI_TRACEPOINTS 118 select DYNAMIC_FTRACE if FUNCTION_TRACER 119 select DMA_BOUNCE_UNALIGNED_KMALLOC 120 select DMA_DIRECT_REMAP 121 select EDAC_SUPPORT 122 select FRAME_POINTER 123 select FUNCTION_ALIGNMENT_4B 124 select FUNCTION_ALIGNMENT_8B if DYNAMIC_FTRACE_WITH_CALL_OPS 125 select GENERIC_ALLOCATOR 126 select GENERIC_ARCH_TOPOLOGY 127 select GENERIC_CLOCKEVENTS_BROADCAST 128 select GENERIC_CPU_AUTOPROBE 129 select GENERIC_CPU_CACHE_MAINTENANCE 130 select GENERIC_CPU_DEVICES 131 select GENERIC_CPU_VULNERABILITIES 132 select GENERIC_EARLY_IOREMAP 133 select GENERIC_IDLE_POLL_SETUP 134 select GENERIC_IOREMAP 135 select GENERIC_IRQ_ENTRY 136 select GENERIC_IRQ_IPI 137 select GENERIC_IRQ_KEXEC_CLEAR_VM_FORWARD 138 select GENERIC_IRQ_PROBE 139 select GENERIC_IRQ_SHOW 140 select GENERIC_IRQ_SHOW_LEVEL 141 select GENERIC_LIB_DEVMEM_IS_ALLOWED 142 select GENERIC_PCI_IOMAP 143 select GENERIC_SCHED_CLOCK 144 select GENERIC_SMP_IDLE_THREAD 145 select GENERIC_GETTIMEOFDAY 146 select HARDIRQS_SW_RESEND 147 select HAS_IOPORT 148 select HAVE_MOVE_PMD 149 select HAVE_MOVE_PUD 150 select HAVE_PCI 151 select HAVE_ACPI_APEI if (ACPI && EFI) 152 select HAVE_ALIGNED_STRUCT_PAGE 153 select HAVE_ARCH_AUDITSYSCALL 154 select HAVE_ARCH_BITREVERSE if BITREVERSE 155 select HAVE_ARCH_COMPILER_H 156 select HAVE_ARCH_HUGE_VMALLOC 157 select HAVE_ARCH_HUGE_VMAP 158 select HAVE_ARCH_JUMP_LABEL 159 select HAVE_ARCH_JUMP_LABEL_RELATIVE 160 select HAVE_ARCH_KASAN 161 select HAVE_ARCH_KASAN_VMALLOC 162 select HAVE_ARCH_KASAN_SW_TAGS 163 select HAVE_ARCH_KASAN_HW_TAGS if ARM64_MTE 164 # Some instrumentation may be unsound, hence EXPERT 165 select HAVE_ARCH_KCSAN if EXPERT 166 select HAVE_ARCH_KFENCE 167 select HAVE_ARCH_KGDB 168 select HAVE_ARCH_KSTACK_ERASE 169 select HAVE_ARCH_MMAP_RND_BITS 170 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT 171 select HAVE_ARCH_PREL32_RELOCATIONS 172 select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET 173 select HAVE_ARCH_SECCOMP_FILTER 174 select HAVE_ARCH_THREAD_STRUCT_WHITELIST 175 select HAVE_ARCH_TRACEHOOK 176 select HAVE_ARCH_TRANSPARENT_HUGEPAGE 177 select HAVE_ARCH_VMAP_STACK 178 select HAVE_ARM_SMCCC 179 select HAVE_ASM_MODVERSIONS 180 select HAVE_EBPF_JIT 181 select HAVE_C_RECORDMCOUNT 182 select HAVE_CMPXCHG_DOUBLE 183 select HAVE_CMPXCHG_LOCAL 184 select HAVE_CONTEXT_TRACKING_USER 185 select HAVE_DEBUG_KMEMLEAK 186 select HAVE_DMA_CONTIGUOUS 187 select HAVE_DYNAMIC_FTRACE 188 select HAVE_DYNAMIC_FTRACE_WITH_ARGS \ 189 if (GCC_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS || \ 190 CLANG_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS) 191 select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS \ 192 if DYNAMIC_FTRACE_WITH_ARGS 193 select HAVE_DYNAMIC_FTRACE_WITH_CALL_OPS \ 194 if (DYNAMIC_FTRACE_WITH_ARGS && !CFI && \ 195 (CC_IS_CLANG || !CC_OPTIMIZE_FOR_SIZE)) 196 select FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY \ 197 if DYNAMIC_FTRACE_WITH_ARGS 198 select HAVE_SAMPLE_FTRACE_DIRECT 199 select HAVE_SAMPLE_FTRACE_DIRECT_MULTI 200 select HAVE_BUILDTIME_MCOUNT_SORT 201 select HAVE_EFFICIENT_UNALIGNED_ACCESS 202 select HAVE_GUP_FAST 203 select HAVE_FTRACE_GRAPH_FUNC 204 select HAVE_FUNCTION_TRACER 205 select HAVE_FUNCTION_ERROR_INJECTION 206 select HAVE_FUNCTION_GRAPH_FREGS 207 select HAVE_FUNCTION_GRAPH_TRACER 208 select HAVE_GCC_PLUGINS 209 select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && \ 210 HW_PERF_EVENTS && HAVE_PERF_EVENTS_NMI 211 select HAVE_HW_BREAKPOINT if PERF_EVENTS 212 select HAVE_IOREMAP_PROT 213 select HAVE_IRQ_TIME_ACCOUNTING 214 select HAVE_LIVEPATCH 215 select HAVE_MOD_ARCH_SPECIFIC 216 select HAVE_NMI 217 select HAVE_PERF_EVENTS 218 select HAVE_PERF_EVENTS_NMI if ARM64_PSEUDO_NMI 219 select HAVE_PERF_REGS 220 select HAVE_PERF_USER_STACK_DUMP 221 select HAVE_REGS_AND_STACK_ACCESS_API 222 select HAVE_RELIABLE_STACKTRACE 223 select HAVE_POSIX_CPU_TIMERS_TASK_WORK 224 select HAVE_FUNCTION_ARG_ACCESS_API 225 select MMU_GATHER_RCU_TABLE_FREE 226 select HAVE_RSEQ 227 select HAVE_RUST 228 select HAVE_STACKPROTECTOR 229 select HAVE_STATIC_CALL if CFI 230 select HAVE_SYSCALL_TRACEPOINTS 231 select HAVE_KPROBES 232 select HAVE_KRETPROBES 233 select HOTPLUG_CORE_SYNC_DEAD if HOTPLUG_CPU 234 select HOTPLUG_SMT if HOTPLUG_CPU 235 select IRQ_DOMAIN 236 select IRQ_FORCED_THREADING 237 select JUMP_LABEL 238 select KASAN_VMALLOC if KASAN 239 select LOCK_MM_AND_FIND_VMA 240 select MODULES_USE_ELF_RELA 241 select NEED_DMA_MAP_STATE 242 select NEED_SG_DMA_LENGTH 243 select OF 244 select OF_EARLY_FLATTREE 245 select PCI_DOMAINS_GENERIC if PCI 246 select PCI_ECAM if (ACPI && PCI) 247 select PCI_SYSCALL if PCI 248 select POWER_RESET 249 select POWER_SUPPLY 250 select HAS_SEPARATE_PREEMPT_RESCHED_BITS 251 select SPARSE_IRQ 252 select SWIOTLB 253 select SYSCTL_EXCEPTION_TRACE 254 select THREAD_INFO_IN_TASK 255 select HAVE_ARCH_USERFAULTFD_MINOR if USERFAULTFD 256 select HAVE_ARCH_USERFAULTFD_WP if USERFAULTFD 257 select TRACE_IRQFLAGS_SUPPORT 258 select TRACE_IRQFLAGS_NMI_SUPPORT 259 select HAVE_SOFTIRQ_ON_OWN_STACK 260 select USER_STACKTRACE_SUPPORT 261 select VDSO_GETRANDOM 262 select VMAP_STACK 263 help 264 ARM 64-bit (AArch64) Linux support. 265 266config CLANG_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS 267 def_bool CC_IS_CLANG 268 # https://github.com/ClangBuiltLinux/linux/issues/1507 269 depends on AS_IS_GNU || (AS_IS_LLVM && (LD_IS_LLD || LD_VERSION >= 23600)) 270 271config GCC_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS 272 def_bool CC_IS_GCC 273 depends on $(cc-option,-fpatchable-function-entry=2) 274 275config 64BIT 276 def_bool y 277 278config MMU 279 def_bool y 280 281config ARM64_CONT_PTE_SHIFT 282 int 283 default 5 if PAGE_SIZE_64KB 284 default 7 if PAGE_SIZE_16KB 285 default 4 286 287config ARM64_CONT_PMD_SHIFT 288 int 289 default 5 if PAGE_SIZE_64KB 290 default 5 if PAGE_SIZE_16KB 291 default 4 292 293config ARCH_MMAP_RND_BITS_MIN 294 default 14 if PAGE_SIZE_64KB 295 default 16 if PAGE_SIZE_16KB 296 default 18 297 298# max bits determined by the following formula: 299# VA_BITS - PTDESC_TABLE_SHIFT 300config ARCH_MMAP_RND_BITS_MAX 301 default 19 if ARM64_VA_BITS=36 302 default 24 if ARM64_VA_BITS=39 303 default 27 if ARM64_VA_BITS=42 304 default 30 if ARM64_VA_BITS=47 305 default 29 if (ARM64_VA_BITS=48 || ARM64_VA_BITS=52) && ARM64_64K_PAGES 306 default 31 if (ARM64_VA_BITS=48 || ARM64_VA_BITS=52) && ARM64_16K_PAGES 307 default 33 if (ARM64_VA_BITS=48 || ARM64_VA_BITS=52) 308 default 14 if ARM64_64K_PAGES 309 default 16 if ARM64_16K_PAGES 310 default 18 311 312# default to 1 TiB (5 bits below ARCH_MMAP_RND_BITS_MAX) on 48-bit and 313# 52-bit VA; smaller VA sizes fall back to ARCH_MMAP_RND_BITS_MIN in 314# arch/Kconfig 315config ARCH_MMAP_RND_BITS 316 default 24 if (ARM64_VA_BITS=48 || ARM64_VA_BITS=52) && ARM64_64K_PAGES 317 default 26 if (ARM64_VA_BITS=48 || ARM64_VA_BITS=52) && ARM64_16K_PAGES 318 default 28 if (ARM64_VA_BITS=48 || ARM64_VA_BITS=52) 319 320config ARCH_MMAP_RND_COMPAT_BITS_MIN 321 default 7 if ARM64_64K_PAGES 322 default 9 if ARM64_16K_PAGES 323 default 11 324 325config ARCH_MMAP_RND_COMPAT_BITS_MAX 326 default 16 327 328config NO_IOPORT_MAP 329 def_bool y if !PCI 330 331config STACKTRACE_SUPPORT 332 def_bool y 333 334config ILLEGAL_POINTER_VALUE 335 hex 336 default 0xdead000000000000 337 338config LOCKDEP_SUPPORT 339 def_bool y 340 341config GENERIC_BUG 342 def_bool y 343 depends on BUG 344 345config GENERIC_BUG_RELATIVE_POINTERS 346 def_bool y 347 depends on GENERIC_BUG 348 349config GENERIC_HWEIGHT 350 def_bool y 351 352config GENERIC_CSUM 353 def_bool y 354 355config GENERIC_CALIBRATE_DELAY 356 def_bool y 357 358config SMP 359 def_bool y 360 361config KERNEL_MODE_NEON 362 def_bool y 363 364config FIX_EARLYCON_MEM 365 def_bool y 366 367config PGTABLE_LEVELS 368 int 369 default 2 if ARM64_16K_PAGES && ARM64_VA_BITS_36 370 default 2 if ARM64_64K_PAGES && ARM64_VA_BITS_42 371 default 3 if ARM64_64K_PAGES && (ARM64_VA_BITS_48 || ARM64_VA_BITS_52) 372 default 3 if ARM64_4K_PAGES && ARM64_VA_BITS_39 373 default 3 if ARM64_16K_PAGES && ARM64_VA_BITS_47 374 default 4 if ARM64_16K_PAGES && (ARM64_VA_BITS_48 || ARM64_VA_BITS_52) 375 default 4 if !ARM64_64K_PAGES && ARM64_VA_BITS_48 376 default 5 if ARM64_4K_PAGES && ARM64_VA_BITS_52 377 378config ARCH_SUPPORTS_UPROBES 379 def_bool y 380 381config ARCH_PROC_KCORE_TEXT 382 def_bool y 383 384config BROKEN_GAS_INST 385 def_bool !$(as-instr,1:\n.inst 0\n.rept . - 1b\n\nnop\n.endr\n) 386 387config BUILTIN_RETURN_ADDRESS_STRIPS_PAC 388 bool 389 # Clang's __builtin_return_address() strips the PAC since 12.0.0 390 # https://github.com/llvm/llvm-project/commit/2a96f47c5ffca84cd774ad402cacd137f4bf45e2 391 default y if CC_IS_CLANG 392 # GCC's __builtin_return_address() strips the PAC since 11.1.0, 393 # and this was backported to 10.2.0, 9.4.0, 8.5.0, but not earlier 394 # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94891 395 default y if CC_IS_GCC && (GCC_VERSION >= 110100) 396 default y if CC_IS_GCC && (GCC_VERSION >= 100200) && (GCC_VERSION < 110000) 397 default y if CC_IS_GCC && (GCC_VERSION >= 90400) && (GCC_VERSION < 100000) 398 default y if CC_IS_GCC && (GCC_VERSION >= 80500) && (GCC_VERSION < 90000) 399 default n 400 401config KASAN_SHADOW_OFFSET 402 hex 403 depends on KASAN_GENERIC || KASAN_SW_TAGS 404 default 0xdfff800000000000 if (ARM64_VA_BITS_48 || (ARM64_VA_BITS_52 && !ARM64_16K_PAGES)) && !KASAN_SW_TAGS 405 default 0xdfffc00000000000 if (ARM64_VA_BITS_47 || ARM64_VA_BITS_52) && ARM64_16K_PAGES && !KASAN_SW_TAGS 406 default 0xdffffe0000000000 if ARM64_VA_BITS_42 && !KASAN_SW_TAGS 407 default 0xdfffffc000000000 if ARM64_VA_BITS_39 && !KASAN_SW_TAGS 408 default 0xdffffff800000000 if ARM64_VA_BITS_36 && !KASAN_SW_TAGS 409 default 0xefff800000000000 if (ARM64_VA_BITS_48 || (ARM64_VA_BITS_52 && !ARM64_16K_PAGES)) && KASAN_SW_TAGS 410 default 0xefffc00000000000 if (ARM64_VA_BITS_47 || ARM64_VA_BITS_52) && ARM64_16K_PAGES && KASAN_SW_TAGS 411 default 0xeffffe0000000000 if ARM64_VA_BITS_42 && KASAN_SW_TAGS 412 default 0xefffffc000000000 if ARM64_VA_BITS_39 && KASAN_SW_TAGS 413 default 0xeffffff800000000 if ARM64_VA_BITS_36 && KASAN_SW_TAGS 414 default 0xffffffffffffffff 415 416config UNWIND_TABLES 417 bool 418 419source "arch/arm64/Kconfig.platforms" 420 421menu "Kernel Features" 422 423menu "ARM errata workarounds via the alternatives framework" 424 425config AMPERE_ERRATUM_AC03_CPU_38 426 bool "AmpereOne: AC03_CPU_38: Certain bits in the Virtualization Translation Control Register and Translation Control Registers do not follow RES0 semantics" 427 default y 428 help 429 This option adds an alternative code sequence to work around Ampere 430 errata AC03_CPU_38 and AC04_CPU_10 on AmpereOne. 431 432 The affected design reports FEAT_HAFDBS as not implemented in 433 ID_AA64MMFR1_EL1.HAFDBS, but (V)TCR_ELx.{HA,HD} are not RES0 434 as required by the architecture. The unadvertised HAFDBS 435 implementation suffers from an additional erratum where hardware 436 A/D updates can occur after a PTE has been marked invalid. 437 438 The workaround forces KVM to explicitly set VTCR_EL2.HA to 0, 439 which avoids enabling unadvertised hardware Access Flag management 440 at stage-2. 441 442 If unsure, say Y. 443 444config AMPERE_ERRATUM_AC04_CPU_23 445 bool "AmpereOne: AC04_CPU_23: Failure to synchronize writes to HCR_EL2 may corrupt address translations." 446 default y 447 help 448 This option adds an alternative code sequence to work around Ampere 449 errata AC04_CPU_23 on AmpereOne. 450 451 Updates to HCR_EL2 can rarely corrupt simultaneous translations for 452 data addresses initiated by load/store instructions. Only 453 instruction initiated translations are vulnerable, not translations 454 from prefetches for example. A DSB before the store to HCR_EL2 is 455 sufficient to prevent older instructions from hitting the window 456 for corruption, and an ISB after is sufficient to prevent younger 457 instructions from hitting the window for corruption. 458 459 If unsure, say Y. 460 461config ARM64_WORKAROUND_CLEAN_CACHE 462 bool 463 464config ARM64_ERRATUM_826319 465 bool "Cortex-A53: 826319: System might deadlock if a write cannot complete until read data is accepted" 466 default y 467 select ARM64_WORKAROUND_CLEAN_CACHE 468 help 469 This option adds an alternative code sequence to work around ARM 470 erratum 826319 on Cortex-A53 parts up to r0p2 with an AMBA 4 ACE or 471 AXI master interface and an L2 cache. 472 473 If a Cortex-A53 uses an AMBA AXI4 ACE interface to other processors 474 and is unable to accept a certain write via this interface, it will 475 not progress on read data presented on the read data channel and the 476 system can deadlock. 477 478 The workaround promotes data cache clean instructions to 479 data cache clean-and-invalidate. 480 Please note that this does not necessarily enable the workaround, 481 as it depends on the alternative framework, which will only patch 482 the kernel if an affected CPU is detected. 483 484 If unsure, say Y. 485 486config ARM64_ERRATUM_827319 487 bool "Cortex-A53: 827319: Data cache clean instructions might cause overlapping transactions to the interconnect" 488 default y 489 select ARM64_WORKAROUND_CLEAN_CACHE 490 help 491 This option adds an alternative code sequence to work around ARM 492 erratum 827319 on Cortex-A53 parts up to r0p2 with an AMBA 5 CHI 493 master interface and an L2 cache. 494 495 Under certain conditions this erratum can cause a clean line eviction 496 to occur at the same time as another transaction to the same address 497 on the AMBA 5 CHI interface, which can cause data corruption if the 498 interconnect reorders the two transactions. 499 500 The workaround promotes data cache clean instructions to 501 data cache clean-and-invalidate. 502 Please note that this does not necessarily enable the workaround, 503 as it depends on the alternative framework, which will only patch 504 the kernel if an affected CPU is detected. 505 506 If unsure, say Y. 507 508config ARM64_ERRATUM_824069 509 bool "Cortex-A53: 824069: Cache line might not be marked as clean after a CleanShared snoop" 510 default y 511 select ARM64_WORKAROUND_CLEAN_CACHE 512 help 513 This option adds an alternative code sequence to work around ARM 514 erratum 824069 on Cortex-A53 parts up to r0p2 when it is connected 515 to a coherent interconnect. 516 517 If a Cortex-A53 processor is executing a store or prefetch for 518 write instruction at the same time as a processor in another 519 cluster is executing a cache maintenance operation to the same 520 address, then this erratum might cause a clean cache line to be 521 incorrectly marked as dirty. 522 523 The workaround promotes data cache clean instructions to 524 data cache clean-and-invalidate. 525 Please note that this option does not necessarily enable the 526 workaround, as it depends on the alternative framework, which will 527 only patch the kernel if an affected CPU is detected. 528 529 If unsure, say Y. 530 531config ARM64_ERRATUM_819472 532 bool "Cortex-A53: 819472: Store exclusive instructions might cause data corruption" 533 default y 534 select ARM64_WORKAROUND_CLEAN_CACHE 535 help 536 This option adds an alternative code sequence to work around ARM 537 erratum 819472 on Cortex-A53 parts up to r0p1 with an L2 cache 538 present when it is connected to a coherent interconnect. 539 540 If the processor is executing a load and store exclusive sequence at 541 the same time as a processor in another cluster is executing a cache 542 maintenance operation to the same address, then this erratum might 543 cause data corruption. 544 545 The workaround promotes data cache clean instructions to 546 data cache clean-and-invalidate. 547 Please note that this does not necessarily enable the workaround, 548 as it depends on the alternative framework, which will only patch 549 the kernel if an affected CPU is detected. 550 551 If unsure, say Y. 552 553config ARM64_ERRATUM_832075 554 bool "Cortex-A57: 832075: possible deadlock on mixing exclusive memory accesses with device loads" 555 default y 556 help 557 This option adds an alternative code sequence to work around ARM 558 erratum 832075 on Cortex-A57 parts up to r1p2. 559 560 Affected Cortex-A57 parts might deadlock when exclusive load/store 561 instructions to Write-Back memory are mixed with Device loads. 562 563 The workaround is to promote device loads to use Load-Acquire 564 semantics. 565 Please note that this does not necessarily enable the workaround, 566 as it depends on the alternative framework, which will only patch 567 the kernel if an affected CPU is detected. 568 569 If unsure, say Y. 570 571config ARM64_ERRATUM_834220 572 bool "Cortex-A57: 834220: Stage 2 translation fault might be incorrectly reported in presence of a Stage 1 fault (rare)" 573 depends on KVM 574 help 575 This option adds an alternative code sequence to work around ARM 576 erratum 834220 on Cortex-A57 parts up to r1p2. 577 578 Affected Cortex-A57 parts might report a Stage 2 translation 579 fault as the result of a Stage 1 fault for load crossing a 580 page boundary when there is a permission or device memory 581 alignment fault at Stage 1 and a translation fault at Stage 2. 582 583 The workaround is to verify that the Stage 1 translation 584 doesn't generate a fault before handling the Stage 2 fault. 585 Please note that this does not necessarily enable the workaround, 586 as it depends on the alternative framework, which will only patch 587 the kernel if an affected CPU is detected. 588 589 If unsure, say N. 590 591config ARM64_ERRATUM_1742098 592 bool "Cortex-A57/A72: 1742098: ELR recorded incorrectly on interrupt taken between cryptographic instructions in a sequence" 593 depends on COMPAT 594 default y 595 help 596 This option removes the AES hwcap for aarch32 user-space to 597 workaround erratum 1742098 on Cortex-A57 and Cortex-A72. 598 599 Affected parts may corrupt the AES state if an interrupt is 600 taken between a pair of AES instructions. These instructions 601 are only present if the cryptography extensions are present. 602 All software should have a fallback implementation for CPUs 603 that don't implement the cryptography extensions. 604 605 If unsure, say Y. 606 607config ARM64_ERRATUM_845719 608 bool "Cortex-A53: 845719: a load might read incorrect data" 609 depends on COMPAT 610 default y 611 help 612 This option adds an alternative code sequence to work around ARM 613 erratum 845719 on Cortex-A53 parts up to r0p4. 614 615 When running a compat (AArch32) userspace on an affected Cortex-A53 616 part, a load at EL0 from a virtual address that matches the bottom 32 617 bits of the virtual address used by a recent load at (AArch64) EL1 618 might return incorrect data. 619 620 The workaround is to write the contextidr_el1 register on exception 621 return to a 32-bit task. 622 Please note that this does not necessarily enable the workaround, 623 as it depends on the alternative framework, which will only patch 624 the kernel if an affected CPU is detected. 625 626 If unsure, say Y. 627 628config ARM64_ERRATUM_843419 629 bool "Cortex-A53: 843419: A load or store might access an incorrect address" 630 default y 631 help 632 This option links the kernel with '--fix-cortex-a53-843419' and 633 enables PLT support to replace certain ADRP instructions, which can 634 cause subsequent memory accesses to use an incorrect address on 635 Cortex-A53 parts up to r0p4. 636 637 If unsure, say Y. 638 639config ARM64_ERRATUM_1024718 640 bool "Cortex-A55: 1024718: Update of DBM/AP bits without break before make might result in incorrect update" 641 default y 642 help 643 This option adds a workaround for ARM Cortex-A55 Erratum 1024718. 644 645 Affected Cortex-A55 cores (all revisions) could cause incorrect 646 update of the hardware dirty bit when the DBM/AP bits are updated 647 without a break-before-make. The workaround is to disable the usage 648 of hardware DBM locally on the affected cores. CPUs not affected by 649 this erratum will continue to use the feature. 650 651 If unsure, say Y. 652 653config ARM64_ERRATUM_1418040 654 bool "Cortex-A76/Neoverse-N1: MRC read following MRRC read of specific Generic Timer in AArch32 might give incorrect result" 655 default y 656 depends on COMPAT 657 help 658 This option adds a workaround for ARM Cortex-A76/Neoverse-N1 659 errata 1188873 and 1418040. 660 661 Affected Cortex-A76/Neoverse-N1 cores (r0p0 to r3p1) could 662 cause register corruption when accessing the timer registers 663 from AArch32 userspace. 664 665 If unsure, say Y. 666 667config ARM64_WORKAROUND_SPECULATIVE_AT 668 bool 669 670config ARM64_ERRATUM_1165522 671 bool "Cortex-A76: 1165522: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation" 672 default y 673 select ARM64_WORKAROUND_SPECULATIVE_AT 674 help 675 This option adds a workaround for ARM Cortex-A76 erratum 1165522. 676 677 Affected Cortex-A76 cores (r0p0, r1p0, r2p0) could end-up with 678 corrupted TLBs by speculating an AT instruction during a guest 679 context switch. 680 681 If unsure, say Y. 682 683config ARM64_ERRATUM_1319367 684 bool "Cortex-A57/A72: 1319537: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation" 685 default y 686 select ARM64_WORKAROUND_SPECULATIVE_AT 687 help 688 This option adds work arounds for ARM Cortex-A57 erratum 1319537 689 and A72 erratum 1319367 690 691 Cortex-A57 and A72 cores could end-up with corrupted TLBs by 692 speculating an AT instruction during a guest context switch. 693 694 If unsure, say Y. 695 696config ARM64_ERRATUM_1530923 697 bool "Cortex-A55: 1530923: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation" 698 default y 699 select ARM64_WORKAROUND_SPECULATIVE_AT 700 help 701 This option adds a workaround for ARM Cortex-A55 erratum 1530923. 702 703 Affected Cortex-A55 cores (r0p0, r0p1, r1p0, r2p0) could end-up with 704 corrupted TLBs by speculating an AT instruction during a guest 705 context switch. 706 707 If unsure, say Y. 708 709config ARM64_WORKAROUND_REPEAT_TLBI_SYNC 710 bool 711 # This workaround is (only) suitable for TLB invalidation errata where 712 # all of the following conditions are true: 713 # 714 # - The effects of the errata are only a loss of ordering/completion 715 # for explicit memory accesses when the TLBI is completed with a DSB. 716 # The removal of TLB entries is not affected. 717 # 718 # Note that architecturally, S2-only invalidation does not remove 719 # combined S1+S2 entries, and does not complete accesses translated 720 # via those S1+S2 entries. Consequently, where this condition holds, 721 # the errata do not affect S2-only invalidation. 722 # 723 # - The errata only affect broadcast TLB invalidation operations (e.g. 724 # TLBI VMALLE1IS), and do not affect local TLB invalidation 725 # operations (e.g. TLBI VMALLE1). 726 # 727 # - After any number of affected TLBI operations are completed with a 728 # DSB, the errata can be mitigated by executing a single arbitrary 729 # broadcast TLBI (which targets an arbitrary translation regime), 730 # followed by a DSB. 731 # 732 # For more rationale, see commit a8f78680ee6bf795. 733 734config ARM64_ERRATUM_2441007 735 bool "Cortex-A55: Completion of affected memory accesses might not be guaranteed by completion of a TLBI (rare)" 736 select ARM64_WORKAROUND_REPEAT_TLBI_SYNC 737 help 738 This option adds a workaround for ARM Cortex-A55 erratum #2441007. 739 740 Under very rare circumstances, affected Cortex-A55 CPUs 741 may not handle a race between a break-before-make sequence on one 742 CPU, and another CPU accessing the same page. This could allow a 743 store to a page that has been unmapped. 744 745 Work around this by adding the affected CPUs to the list that needs 746 TLB sequences to be done twice. 747 748 If unsure, say N. 749 750config ARM64_ERRATUM_1286807 751 bool "Cortex-A76: Modification of the translation table for a virtual address might lead to read-after-read ordering violation (rare)" 752 select ARM64_WORKAROUND_REPEAT_TLBI_SYNC 753 help 754 This option adds a workaround for ARM Cortex-A76 erratum 1286807. 755 756 On the affected Cortex-A76 cores (r0p0 to r3p0), if a virtual 757 address for a cacheable mapping of a location is being 758 accessed by a core while another core is remapping the virtual 759 address to a new physical page using the recommended 760 break-before-make sequence, then under very rare circumstances 761 TLBI+DSB completes before a read using the translation being 762 invalidated has been observed by other observers. The 763 workaround repeats the TLBI+DSB operation. 764 765 If unsure, say N. 766 767config ARM64_ERRATUM_1463225 768 bool "Cortex-A76: Software Step might prevent interrupt recognition" 769 default y 770 help 771 This option adds a workaround for Arm Cortex-A76 erratum 1463225. 772 773 On the affected Cortex-A76 cores (r0p0 to r3p1), software stepping 774 of a system call instruction (SVC) can prevent recognition of 775 subsequent interrupts when software stepping is disabled in the 776 exception handler of the system call and either kernel debugging 777 is enabled or VHE is in use. 778 779 Work around the erratum by triggering a dummy step exception 780 when handling a system call from a task that is being stepped 781 in a VHE configuration of the kernel. 782 783 If unsure, say Y. 784 785config ARM64_ERRATUM_1542419 786 bool "Neoverse-N1: workaround mis-ordering of instruction fetches (rare)" 787 help 788 This option adds a workaround for ARM Neoverse-N1 erratum 789 1542419. 790 791 Affected Neoverse-N1 cores could execute a stale instruction when 792 modified by another CPU. The workaround depends on a firmware 793 counterpart. 794 795 Workaround the issue by hiding the DIC feature from EL0. This 796 forces user-space to perform cache maintenance. 797 798 If unsure, say N. 799 800config ARM64_ERRATUM_1508412 801 bool "Cortex-A77: 1508412: workaround deadlock on sequence of NC/Device load and store exclusive or PAR read" 802 default y 803 help 804 This option adds a workaround for Arm Cortex-A77 erratum 1508412. 805 806 Affected Cortex-A77 cores (r0p0, r1p0) could deadlock on a sequence 807 of a store-exclusive or read of PAR_EL1 and a load with device or 808 non-cacheable memory attributes. The workaround depends on a firmware 809 counterpart. 810 811 KVM guests must also have the workaround implemented or they can 812 deadlock the system. 813 814 Work around the issue by inserting DMB SY barriers around PAR_EL1 815 register reads and warning KVM users. The DMB barrier is sufficient 816 to prevent a speculative PAR_EL1 read. 817 818 If unsure, say Y. 819 820config ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE 821 bool 822 823config ARM64_ERRATUM_2051678 824 bool "Cortex-A510: 2051678: disable Hardware Update of the page table dirty bit" 825 default y 826 help 827 This options adds the workaround for ARM Cortex-A510 erratum ARM64_ERRATUM_2051678. 828 Affected Cortex-A510 might not respect the ordering rules for 829 hardware update of the page table's dirty bit. The workaround 830 is to not enable the feature on affected CPUs. 831 832 If unsure, say Y. 833 834config ARM64_ERRATUM_2077057 835 bool "Cortex-A510: 2077057: workaround software-step corrupting SPSR_EL2" 836 default y 837 help 838 This option adds the workaround for ARM Cortex-A510 erratum 2077057. 839 Affected Cortex-A510 may corrupt SPSR_EL2 when the a step exception is 840 expected, but a Pointer Authentication trap is taken instead. The 841 erratum causes SPSR_EL1 to be copied to SPSR_EL2, which could allow 842 EL1 to cause a return to EL2 with a guest controlled ELR_EL2. 843 844 This can only happen when EL2 is stepping EL1. 845 846 When these conditions occur, the SPSR_EL2 value is unchanged from the 847 previous guest entry, and can be restored from the in-memory copy. 848 849 If unsure, say Y. 850 851config ARM64_ERRATUM_2658417 852 bool "Cortex-A510: 2658417: remove BF16 support due to incorrect result" 853 default y 854 help 855 This option adds the workaround for ARM Cortex-A510 erratum 2658417. 856 Affected Cortex-A510 (r0p0 to r1p1) may produce the wrong result for 857 BFMMLA or VMMLA instructions in rare circumstances when a pair of 858 A510 CPUs are using shared neon hardware. As the sharing is not 859 discoverable by the kernel, hide the BF16 HWCAP to indicate that 860 user-space should not be using these instructions. 861 862 If unsure, say Y. 863 864config ARM64_ERRATUM_2119858 865 bool "Cortex-A710/X2: 2119858: workaround TRBE overwriting trace data in FILL mode" 866 default y 867 depends on CORESIGHT_TRBE 868 select ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE 869 help 870 This option adds the workaround for ARM Cortex-A710/X2 erratum 2119858. 871 872 Affected Cortex-A710/X2 cores could overwrite up to 3 cache lines of trace 873 data at the base of the buffer (pointed to by TRBASER_EL1) in FILL mode in 874 the event of a WRAP event. 875 876 Work around the issue by always making sure we move the TRBPTR_EL1 by 877 256 bytes before enabling the buffer and filling the first 256 bytes of 878 the buffer with ETM ignore packets upon disabling. 879 880 If unsure, say Y. 881 882config ARM64_ERRATUM_2139208 883 bool "Neoverse-N2: 2139208: workaround TRBE overwriting trace data in FILL mode" 884 default y 885 depends on CORESIGHT_TRBE 886 select ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE 887 help 888 This option adds the workaround for ARM Neoverse-N2 erratum 2139208. 889 890 Affected Neoverse-N2 cores could overwrite up to 3 cache lines of trace 891 data at the base of the buffer (pointed to by TRBASER_EL1) in FILL mode in 892 the event of a WRAP event. 893 894 Work around the issue by always making sure we move the TRBPTR_EL1 by 895 256 bytes before enabling the buffer and filling the first 256 bytes of 896 the buffer with ETM ignore packets upon disabling. 897 898 If unsure, say Y. 899 900config ARM64_WORKAROUND_TSB_FLUSH_FAILURE 901 bool 902 903config ARM64_ERRATUM_2054223 904 bool "Cortex-A710: 2054223: workaround TSB instruction failing to flush trace" 905 default y 906 select ARM64_WORKAROUND_TSB_FLUSH_FAILURE 907 help 908 Enable workaround for ARM Cortex-A710 erratum 2054223 909 910 Affected cores may fail to flush the trace data on a TSB instruction, when 911 the PE is in trace prohibited state. This will cause losing a few bytes 912 of the trace cached. 913 914 Workaround is to issue two TSB consecutively on affected cores. 915 916 If unsure, say Y. 917 918config ARM64_ERRATUM_2067961 919 bool "Neoverse-N2: 2067961: workaround TSB instruction failing to flush trace" 920 default y 921 select ARM64_WORKAROUND_TSB_FLUSH_FAILURE 922 help 923 Enable workaround for ARM Neoverse-N2 erratum 2067961 924 925 Affected cores may fail to flush the trace data on a TSB instruction, when 926 the PE is in trace prohibited state. This will cause losing a few bytes 927 of the trace cached. 928 929 Workaround is to issue two TSB consecutively on affected cores. 930 931 If unsure, say Y. 932 933config ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE 934 bool 935 936config ARM64_ERRATUM_2253138 937 bool "Neoverse-N2: 2253138: workaround TRBE writing to address out-of-range" 938 depends on CORESIGHT_TRBE 939 default y 940 select ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE 941 help 942 This option adds the workaround for ARM Neoverse-N2 erratum 2253138. 943 944 Affected Neoverse-N2 cores might write to an out-of-range address, not reserved 945 for TRBE. Under some conditions, the TRBE might generate a write to the next 946 virtually addressed page following the last page of the TRBE address space 947 (i.e., the TRBLIMITR_EL1.LIMIT), instead of wrapping around to the base. 948 949 Work around this in the driver by always making sure that there is a 950 page beyond the TRBLIMITR_EL1.LIMIT, within the space allowed for the TRBE. 951 952 If unsure, say Y. 953 954config ARM64_ERRATUM_2224489 955 bool "Cortex-A710/X2: 2224489: workaround TRBE writing to address out-of-range" 956 depends on CORESIGHT_TRBE 957 default y 958 select ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE 959 help 960 This option adds the workaround for ARM Cortex-A710/X2 erratum 2224489. 961 962 Affected Cortex-A710/X2 cores might write to an out-of-range address, not reserved 963 for TRBE. Under some conditions, the TRBE might generate a write to the next 964 virtually addressed page following the last page of the TRBE address space 965 (i.e., the TRBLIMITR_EL1.LIMIT), instead of wrapping around to the base. 966 967 Work around this in the driver by always making sure that there is a 968 page beyond the TRBLIMITR_EL1.LIMIT, within the space allowed for the TRBE. 969 970 If unsure, say Y. 971 972config ARM64_ERRATUM_2441009 973 bool "Cortex-A510: Completion of affected memory accesses might not be guaranteed by completion of a TLBI (rare)" 974 select ARM64_WORKAROUND_REPEAT_TLBI_SYNC 975 help 976 This option adds a workaround for ARM Cortex-A510 erratum #2441009. 977 978 Under very rare circumstances, affected Cortex-A510 CPUs 979 may not handle a race between a break-before-make sequence on one 980 CPU, and another CPU accessing the same page. This could allow a 981 store to a page that has been unmapped. 982 983 Work around this by adding the affected CPUs to the list that needs 984 TLB sequences to be done twice. 985 986 If unsure, say N. 987 988config ARM64_ERRATUM_2064142 989 bool "Cortex-A510: 2064142: workaround TRBE register writes while disabled" 990 depends on CORESIGHT_TRBE 991 default y 992 help 993 This option adds the workaround for ARM Cortex-A510 erratum 2064142. 994 995 Affected Cortex-A510 core might fail to write into system registers after the 996 TRBE has been disabled. Under some conditions after the TRBE has been disabled 997 writes into TRBE registers TRBLIMITR_EL1, TRBPTR_EL1, TRBBASER_EL1, TRBSR_EL1, 998 and TRBTRG_EL1 will be ignored and will not be effected. 999 1000 Work around this in the driver by executing TSB CSYNC and DSB after collection 1001 is stopped and before performing a system register write to one of the affected 1002 registers. 1003 1004 If unsure, say Y. 1005 1006config ARM64_ERRATUM_2038923 1007 bool "Cortex-A510: 2038923: workaround TRBE corruption with enable" 1008 depends on CORESIGHT_TRBE 1009 default y 1010 help 1011 This option adds the workaround for ARM Cortex-A510 erratum 2038923. 1012 1013 Affected Cortex-A510 core might cause an inconsistent view on whether trace is 1014 prohibited within the CPU. As a result, the trace buffer or trace buffer state 1015 might be corrupted. This happens after TRBE buffer has been enabled by setting 1016 TRBLIMITR_EL1.E, followed by just a single context synchronization event before 1017 execution changes from a context, in which trace is prohibited to one where it 1018 isn't, or vice versa. In these mentioned conditions, the view of whether trace 1019 is prohibited is inconsistent between parts of the CPU, and the trace buffer or 1020 the trace buffer state might be corrupted. 1021 1022 Work around this in the driver by preventing an inconsistent view of whether the 1023 trace is prohibited or not based on TRBLIMITR_EL1.E by immediately following a 1024 change to TRBLIMITR_EL1.E with at least one ISB instruction before an ERET, or 1025 two ISB instructions if no ERET is to take place. 1026 1027 If unsure, say Y. 1028 1029config ARM64_ERRATUM_1902691 1030 bool "Cortex-A510: 1902691: workaround TRBE trace corruption" 1031 depends on CORESIGHT_TRBE 1032 default y 1033 help 1034 This option adds the workaround for ARM Cortex-A510 erratum 1902691. 1035 1036 Affected Cortex-A510 core might cause trace data corruption, when being written 1037 into the memory. Effectively TRBE is broken and hence cannot be used to capture 1038 trace data. 1039 1040 Work around this problem in the driver by just preventing TRBE initialization on 1041 affected cpus. The firmware must have disabled the access to TRBE for the kernel 1042 on such implementations. This will cover the kernel for any firmware that doesn't 1043 do this already. 1044 1045 If unsure, say Y. 1046 1047config ARM64_WORKAROUND_BROKEN_AMU_CONSTCNT 1048 bool 1049 # Targeting errata affecting AMEVCNTR01, the AMU constant counter. 1050 # On affected CPUs the counter may not increment at the expected rate, 1051 # making it unreliable. As a result, AMU users should treat it as 1052 # unavailable rather than relying on misleading counter values. 1053 1054config ARM64_ERRATUM_2457168 1055 bool "Cortex-A510: 2457168: workaround for AMEVCNTR01 incrementing incorrectly" 1056 depends on ARM64_AMU_EXTN 1057 select ARM64_WORKAROUND_BROKEN_AMU_CONSTCNT 1058 default y 1059 help 1060 This option adds the workaround for ARM Cortex-A510 erratum 2457168. 1061 1062 The AMU counter AMEVCNTR01 (constant counter) should increment at the same rate 1063 as the system counter. On affected Cortex-A510 cores AMEVCNTR01 increments 1064 incorrectly giving a significantly higher output value. 1065 1066 Work around this problem by returning 0 when reading the affected counter in 1067 key locations that results in disabling all users of this counter. This effect 1068 is the same to firmware disabling affected counters. 1069 1070 If unsure, say Y. 1071 1072config ARM64_ERRATUM_2645198 1073 bool "Cortex-A715: 2645198: Workaround possible [ESR|FAR]_ELx corruption" 1074 default y 1075 help 1076 This option adds the workaround for ARM Cortex-A715 erratum 2645198. 1077 1078 If a Cortex-A715 cpu sees a page mapping permissions change from executable 1079 to non-executable, it may corrupt the ESR_ELx and FAR_ELx registers on the 1080 next instruction abort caused by permission fault. 1081 1082 Only user-space does executable to non-executable permission transition via 1083 mprotect() system call. Workaround the problem by doing a break-before-make 1084 TLB invalidation, for all changes to executable user space mappings. 1085 1086 If unsure, say Y. 1087 1088config ARM64_ERRATUM_3821522 1089 bool "Cortex-A725: 3821522: workaround for possible CNT_CYCLES increment error due to WFE/WFI" 1090 depends on ARM64_AMU_EXTN 1091 select ARM64_WORKAROUND_BROKEN_AMU_CONSTCNT 1092 default y 1093 help 1094 This option adds the workaround for ARM Cortex-A725 erratum 3821522. 1095 1096 On affected A725 cores, the CNT_CYCLES event may incur a significant 1097 increment error when entering and subsequently exiting WFx. 1098 As a result, the CNT_CYCLES may diverge from the system counter 1099 frequency at which it is expected to increment. 1100 This renders the AMU counter AMEVCNTR01, that implements CNT_CYCLES, 1101 being unreliable and unsuitable for use. 1102 1103 Since there is no hardware workaround, reads of the affected CNT_CYCLES 1104 counter return 0 in the relevant paths. This causes users of the counter 1105 to treat it as unavailable and is functionally equivalent to firmware 1106 disabling the affected counter. 1107 1108 If unsure, say Y. 1109 1110config ARM64_WORKAROUND_SPECULATIVE_UNPRIV_LOAD 1111 bool 1112 1113config ARM64_ERRATUM_2966298 1114 bool "Cortex-A520: 2966298: workaround for speculatively executed unprivileged load" 1115 select ARM64_WORKAROUND_SPECULATIVE_UNPRIV_LOAD 1116 default y 1117 help 1118 This option adds the workaround for ARM Cortex-A520 erratum 2966298. 1119 1120 On an affected Cortex-A520 core, a speculatively executed unprivileged 1121 load might leak data from a privileged level via a cache side channel. 1122 1123 Work around this problem by executing a TLBI before returning to EL0. 1124 1125 If unsure, say Y. 1126 1127config ARM64_ERRATUM_3117295 1128 bool "Cortex-A510: 3117295: workaround for speculatively executed unprivileged load" 1129 select ARM64_WORKAROUND_SPECULATIVE_UNPRIV_LOAD 1130 default y 1131 help 1132 This option adds the workaround for ARM Cortex-A510 erratum 3117295. 1133 1134 On an affected Cortex-A510 core, a speculatively executed unprivileged 1135 load might leak data from a privileged level via a cache side channel. 1136 1137 Work around this problem by executing a TLBI before returning to EL0. 1138 1139 If unsure, say Y. 1140 1141config ARM64_ERRATUM_3194386 1142 bool "Cortex-*/Neoverse-*: workaround for MSR SSBS not self-synchronizing" 1143 default y 1144 help 1145 This option adds the workaround for the following errata: 1146 1147 * ARM Cortex-A76 erratum 3324349 1148 * ARM Cortex-A77 erratum 3324348 1149 * ARM Cortex-A78 erratum 3324344 1150 * ARM Cortex-A78C erratum 3324346 1151 * ARM Cortex-A78C erratum 3324347 1152 * ARM Cortex-A710 erratam 3324338 1153 * ARM Cortex-A715 errartum 3456084 1154 * ARM Cortex-A720 erratum 3456091 1155 * ARM Cortex-A725 erratum 3456106 1156 * ARM Cortex-X1 erratum 3324344 1157 * ARM Cortex-X1C erratum 3324346 1158 * ARM Cortex-X2 erratum 3324338 1159 * ARM Cortex-X3 erratum 3324335 1160 * ARM Cortex-X4 erratum 3194386 1161 * ARM Cortex-X925 erratum 3324334 1162 * ARM Neoverse-N1 erratum 3324349 1163 * ARM Neoverse N2 erratum 3324339 1164 * ARM Neoverse-N3 erratum 3456111 1165 * ARM Neoverse-V1 erratum 3324341 1166 * ARM Neoverse V2 erratum 3324336 1167 * ARM Neoverse-V3 erratum 3312417 1168 * ARM Neoverse-V3AE erratum 3312417 1169 1170 On affected cores "MSR SSBS, #0" instructions may not affect 1171 subsequent speculative instructions, which may permit unexepected 1172 speculative store bypassing. 1173 1174 Work around this problem by placing a Speculation Barrier (SB) or 1175 Instruction Synchronization Barrier (ISB) after kernel changes to 1176 SSBS. The presence of the SSBS special-purpose register is hidden 1177 from hwcaps and EL0 reads of ID_AA64PFR1_EL1, such that userspace 1178 will use the PR_SPEC_STORE_BYPASS prctl to change SSBS. 1179 1180 If unsure, say Y. 1181 1182config ARM64_ERRATUM_4311569 1183 bool "SI L1: 4311569: workaround for premature CMO completion erratum" 1184 default y 1185 help 1186 This option adds the workaround for ARM SI L1 erratum 4311569. 1187 1188 The erratum of SI L1 can cause an early response to a combined write 1189 and cache maintenance operation (WR+CMO) before the operation is fully 1190 completed to the Point of Serialization (POS). 1191 This can result in a non-I/O coherent agent observing stale data, 1192 potentially leading to system instability or incorrect behavior. 1193 1194 Enabling this option implements a software workaround by inserting a 1195 second loop of Cache Maintenance Operation (CMO) immediately following the 1196 end of function to do CMOs. This ensures that the data is correctly serialized 1197 before the buffer is handed off to a non-coherent agent. 1198 1199 If unsure, say Y. 1200 1201config ARM64_ERRATUM_4193714 1202 bool "C1-Pro: 4193714: SME DVMSync early acknowledgement" 1203 depends on ARM64_SME 1204 default y 1205 help 1206 Enable workaround for C1-Pro acknowledging the DVMSync before 1207 the SME memory accesses are complete. This will cause TLB 1208 maintenance for processes using SME to also issue an IPI to 1209 the affected CPUs. 1210 1211 If unsure, say Y. 1212 1213config ARM64_ERRATUM_4118414 1214 bool "Various: Completion of affected memory accesses might not be guaranteed by completion of a TLBI" 1215 default y 1216 select ARM64_WORKAROUND_REPEAT_TLBI_SYNC 1217 help 1218 This option adds a workaround for the following errata: 1219 1220 * ARM C1-Premium erratum 4193780 1221 * ARM C1-Ultra erratum 4193780 1222 * ARM Cortex-A76 erratum 4193800 1223 * ARM Cortex-A76AE erratum 4193801 1224 * ARM Cortex-A77 erratum 4193798 1225 * ARM Cortex-A78 erratum 4193791 1226 * ARM Cortex-A78AE erratum 4193793 1227 * ARM Cortex-A78C erratum 4193794 1228 * ARM Cortex-A710 erratum 4193788 1229 * ARM Cortex-X1 erratum 4193791 1230 * ARM Cortex-X1C erratum 4193792 1231 * ARM Cortex-X2 erratum 4193788 1232 * ARM Cortex-X3 erratum 4193786 1233 * ARM Cortex-X4 erratum 4118414 1234 * ARM Cortex-X925 erratum 4193781 1235 * ARM Neoverse-N1 erratum 4193800 1236 * ARM Neoverse-N2 erratum 4193789 1237 * ARM Neoverse-V1 erratum 4193790 1238 * ARM Neoverse-V2 erratum 4193787 1239 * ARM Neoverse-V3 erratum 4193784 1240 * ARM Neoverse-V3AE erratum 4193784 1241 * Microsoft Azure Cobalt 100 4193789 1242 * NVIDIA Olympus erratum T410-OLY-1029 1243 1244 On affected cores, some memory accesses might not be completed by 1245 broadcast TLB invalidation. 1246 1247 This issue is also known as CVE-2025-10263. 1248 1249 If unsure, say Y. 1250 1251config CAVIUM_ERRATUM_22375 1252 bool "Cavium erratum 22375, 24313" 1253 default y 1254 help 1255 Enable workaround for errata 22375 and 24313. 1256 1257 This implements two gicv3-its errata workarounds for ThunderX. Both 1258 with a small impact affecting only ITS table allocation. 1259 1260 erratum 22375: only alloc 8MB table size 1261 erratum 24313: ignore memory access type 1262 1263 The fixes are in ITS initialization and basically ignore memory access 1264 type and table size provided by the TYPER and BASER registers. 1265 1266 If unsure, say Y. 1267 1268config CAVIUM_ERRATUM_23144 1269 bool "Cavium erratum 23144: ITS SYNC hang on dual socket system" 1270 depends on NUMA 1271 default y 1272 help 1273 ITS SYNC command hang for cross node io and collections/cpu mapping. 1274 1275 If unsure, say Y. 1276 1277config CAVIUM_ERRATUM_23154 1278 bool "Cavium errata 23154 and 38545: GICv3 lacks HW synchronisation" 1279 default y 1280 help 1281 The ThunderX GICv3 implementation requires a modified version for 1282 reading the IAR status to ensure data synchronization 1283 (access to icc_iar1_el1 is not sync'ed before and after). 1284 1285 It also suffers from erratum 38545 (also present on Marvell's 1286 OcteonTX and OcteonTX2), resulting in deactivated interrupts being 1287 spuriously presented to the CPU interface. 1288 1289 If unsure, say Y. 1290 1291config CAVIUM_ERRATUM_27456 1292 bool "Cavium erratum 27456: Broadcast TLBI instructions may cause icache corruption" 1293 default y 1294 help 1295 On ThunderX T88 pass 1.x through 2.1 parts, broadcast TLBI 1296 instructions may cause the icache to become corrupted if it 1297 contains data for a non-current ASID. The fix is to 1298 invalidate the icache when changing the mm context. 1299 1300 If unsure, say Y. 1301 1302config CAVIUM_ERRATUM_30115 1303 bool "Cavium erratum 30115: Guest may disable interrupts in host" 1304 default y 1305 help 1306 On ThunderX T88 pass 1.x through 2.2, T81 pass 1.0 through 1307 1.2, and T83 Pass 1.0, KVM guest execution may disable 1308 interrupts in host. Trapping both GICv3 group-0 and group-1 1309 accesses sidesteps the issue. 1310 1311 If unsure, say Y. 1312 1313config CAVIUM_TX2_ERRATUM_219 1314 bool "Cavium ThunderX2 erratum 219: PRFM between TTBR change and ISB fails" 1315 default y 1316 help 1317 On Cavium ThunderX2, a load, store or prefetch instruction between a 1318 TTBR update and the corresponding context synchronizing operation can 1319 cause a spurious Data Abort to be delivered to any hardware thread in 1320 the CPU core. 1321 1322 Work around the issue by avoiding the problematic code sequence and 1323 trapping KVM guest TTBRx_EL1 writes to EL2 when SMT is enabled. The 1324 trap handler performs the corresponding register access, skips the 1325 instruction and ensures context synchronization by virtue of the 1326 exception return. 1327 1328 If unsure, say Y. 1329 1330config FUJITSU_ERRATUM_010001 1331 bool "Fujitsu-A64FX erratum E#010001: Undefined fault may occur wrongly" 1332 default y 1333 help 1334 This option adds a workaround for Fujitsu-A64FX erratum E#010001. 1335 On some variants of the Fujitsu-A64FX cores ver(1.0, 1.1), memory 1336 accesses may cause undefined fault (Data abort, DFSC=0b111111). 1337 This fault occurs under a specific hardware condition when a 1338 load/store instruction performs an address translation using: 1339 case-1 TTBR0_EL1 with TCR_EL1.NFD0 == 1. 1340 case-2 TTBR0_EL2 with TCR_EL2.NFD0 == 1. 1341 case-3 TTBR1_EL1 with TCR_EL1.NFD1 == 1. 1342 case-4 TTBR1_EL2 with TCR_EL2.NFD1 == 1. 1343 1344 The workaround is to ensure these bits are clear in TCR_ELx. 1345 The workaround only affects the Fujitsu-A64FX. 1346 1347 If unsure, say Y. 1348 1349config HISILICON_ERRATUM_161600802 1350 bool "Hip07 161600802: Erroneous redistributor VLPI base" 1351 default y 1352 help 1353 The HiSilicon Hip07 SoC uses the wrong redistributor base 1354 when issued ITS commands such as VMOVP and VMAPP, and requires 1355 a 128kB offset to be applied to the target address in this commands. 1356 1357 If unsure, say Y. 1358 1359config HISILICON_ERRATUM_162100801 1360 bool "Hip09 162100801 erratum support" 1361 default y 1362 help 1363 When enabling GICv4.1 in hip09, VMAPP will fail to clear some caches 1364 during unmapping operation, which will cause some vSGIs lost. 1365 To fix the issue, invalidate related vPE cache through GICR_INVALLR 1366 after VMOVP. 1367 1368 If unsure, say Y. 1369 1370config HISILICON_ERRATUM_162100125 1371 bool "Hisilicon erratum 162100125" 1372 default y 1373 select ARM64_WORKAROUND_DISABLE_CNP 1374 help 1375 On HiSilicon HIP09, TLB entry matching behavior when CNP 1376 (TTBRx.CNP=1) is enabled differs from the ARM architecture 1377 specification. 1378 1379 TLB entries may be incorrectly shared between CPUs, potentially 1380 causing TLB conflicts and stale mappings. 1381 1382 Disable CNP support for affected HiSilicon HIP09 cores. 1383 1384 If unsure, say Y. 1385 1386config QCOM_FALKOR_ERRATUM_1003 1387 bool "Falkor E1003: Incorrect translation due to ASID change" 1388 default y 1389 help 1390 On Falkor v1, an incorrect ASID may be cached in the TLB when ASID 1391 and BADDR are changed together in TTBRx_EL1. Since we keep the ASID 1392 in TTBR1_EL1, this situation only occurs in the entry trampoline and 1393 then only for entries in the walk cache, since the leaf translation 1394 is unchanged. Work around the erratum by invalidating the walk cache 1395 entries for the trampoline before entering the kernel proper. 1396 1397config QCOM_FALKOR_ERRATUM_1009 1398 bool "Falkor E1009: Prematurely complete a DSB after a TLBI" 1399 default y 1400 select ARM64_WORKAROUND_REPEAT_TLBI_SYNC 1401 help 1402 On Falkor v1, the CPU may prematurely complete a DSB following a 1403 TLBI xxIS invalidate maintenance operation. Repeat the TLBI operation 1404 one more time to fix the issue. 1405 1406 If unsure, say Y. 1407 1408config QCOM_QDF2400_ERRATUM_0065 1409 bool "QDF2400 E0065: Incorrect GITS_TYPER.ITT_Entry_size" 1410 default y 1411 help 1412 On Qualcomm Datacenter Technologies QDF2400 SoC, ITS hardware reports 1413 ITE size incorrectly. The GITS_TYPER.ITT_Entry_size field should have 1414 been indicated as 16Bytes (0xf), not 8Bytes (0x7). 1415 1416 If unsure, say Y. 1417 1418config QCOM_FALKOR_ERRATUM_E1041 1419 bool "Falkor E1041: Speculative instruction fetches might cause errant memory access" 1420 default y 1421 help 1422 Falkor CPU may speculatively fetch instructions from an improper 1423 memory location when MMU translation is changed from SCTLR_ELn[M]=1 1424 to SCTLR_ELn[M]=0. Prefix an ISB instruction to fix the problem. 1425 1426 If unsure, say Y. 1427 1428config ARM64_WORKAROUND_DISABLE_CNP 1429 bool 1430 1431config NVIDIA_CARMEL_CNP_ERRATUM 1432 bool "NVIDIA Carmel CNP: CNP on Carmel semantically different than ARM cores" 1433 default y 1434 select ARM64_WORKAROUND_DISABLE_CNP 1435 help 1436 If CNP is enabled on Carmel cores, non-sharable TLBIs on a core will not 1437 invalidate shared TLB entries installed by a different core, as it would 1438 on standard ARM cores. 1439 1440 If unsure, say Y. 1441 1442config NVIDIA_OLYMPUS_1027_ERRATUM 1443 bool "NVIDIA Olympus: device store/load ordering erratum" 1444 default y 1445 help 1446 This option adds an alternative code sequence to work around an 1447 NVIDIA Olympus core erratum where a Device-nGnR* store can be 1448 observed by a peripheral after a younger Device-nGnR* load to the 1449 same peripheral. This breaks the program order that drivers rely 1450 on for MMIO and can leave a device in an incorrect state. 1451 1452 The workaround inserts a DMB OSH immediately before raw MMIO loads. 1453 The erratum cannot occur when a DMB that orders loads appears 1454 between the store and load, preventing the younger load from being 1455 observed before the older store. 1456 1457 The alternatives framework patches in DMB OSH only when an affected 1458 CPU is detected. Other CPUs execute a NOP in its place. Disabling 1459 this option leaves the original MMIO read instruction stream 1460 unchanged. 1461 1462 If unsure, say Y. 1463 1464config RENESAS_ERRATUM_GEN4GICITS1 1465 bool "Renesas R-Car Gen4: GIC600 can not access physical addresses above 4 GiB" 1466 default y 1467 help 1468 The Renesas R-Car Gen4 S4/V4H/V4M GIC600 SoC integrations have AXI 1469 addressing limited to the first 32-bit of physical address space. 1470 1471 If unsure, say Y. 1472 1473config ROCKCHIP_ERRATUM_3568002 1474 bool "Rockchip 3568002: GIC600 can not access physical addresses higher than 4GB" 1475 default y 1476 help 1477 The Rockchip RK3566 and RK3568 GIC600 SoC integrations have AXI 1478 addressing limited to the first 32bit of physical address space. 1479 1480 If unsure, say Y. 1481 1482config ROCKCHIP_ERRATUM_3588001 1483 bool "Rockchip 3588001: GIC600 can not support shareability attributes" 1484 default y 1485 help 1486 The Rockchip RK3588 GIC600 SoC integration does not support ACE/ACE-lite. 1487 This means, that its sharability feature may not be used, even though it 1488 is supported by the IP itself. 1489 1490 If unsure, say Y. 1491 1492config NXP_IMX8QM_ERRATUM_ERR050104 1493 bool "NXP iMX8QM/QP ERR050104: broken cache/TLB invalidation broadcast" 1494 default y 1495 help 1496 On iMX8QM (QuadMax) and iMX8QP (QuadPlus), address bits above bit 35 1497 in the A53 subsystem ARADDR and ACADDR buses are incorrectly 1498 connected. This corrupts targeted TLBI and IC broadcasts exchanged 1499 between the A53 and A72 core clusters. 1500 1501 Work around this by redirecting targeted TLBI operations to 1502 broadcast-all variants (VMALLE1IS) in the high-level TLB flush 1503 functions, upgrading IC IVAU to IC IALLUIS for both kernel and 1504 user-space, and disabling KVM since correct TLB maintenance 1505 cannot be guaranteed for guests. 1506 1507 The user-space IC IVAU is upgraded by trapping it to the kernel 1508 (SCTLR_EL1.UCI cleared). This also traps the user DC CVAU, DC CVAC, 1509 DC CVAP, DC CVADP and DC CIVAC instructions, making user cache 1510 maintenance slower on the affected SoCs. 1511 1512 If unsure, say Y. 1513 1514config SOCIONEXT_SYNQUACER_PREITS 1515 bool "Socionext Synquacer: Workaround for GICv3 pre-ITS" 1516 default y 1517 help 1518 Socionext Synquacer SoCs implement a separate h/w block to generate 1519 MSI doorbell writes with non-zero values for the device ID. 1520 1521 If unsure, say Y. 1522 1523endmenu # "ARM errata workarounds via the alternatives framework" 1524 1525choice 1526 prompt "Page size" 1527 default ARM64_4K_PAGES 1528 help 1529 Page size (translation granule) configuration. 1530 1531config ARM64_4K_PAGES 1532 bool "4KB" 1533 select HAVE_PAGE_SIZE_4KB 1534 help 1535 This feature enables 4KB pages support. 1536 1537config ARM64_16K_PAGES 1538 bool "16KB" 1539 select HAVE_PAGE_SIZE_16KB 1540 help 1541 The system will use 16KB pages support. AArch32 emulation 1542 requires applications compiled with 16K (or a multiple of 16K) 1543 aligned segments. 1544 1545config ARM64_64K_PAGES 1546 bool "64KB" 1547 select HAVE_PAGE_SIZE_64KB 1548 help 1549 This feature enables 64KB pages support (4KB by default) 1550 allowing only two levels of page tables and faster TLB 1551 look-up. AArch32 emulation requires applications compiled 1552 with 64K aligned segments. 1553 1554endchoice 1555 1556choice 1557 prompt "Virtual address space size" 1558 default ARM64_VA_BITS_52 1559 help 1560 Allows choosing one of multiple possible virtual address 1561 space sizes. The level of translation table is determined by 1562 a combination of page size and virtual address space size. 1563 1564config ARM64_VA_BITS_36 1565 bool "36-bit" if EXPERT 1566 depends on PAGE_SIZE_16KB 1567 1568config ARM64_VA_BITS_39 1569 bool "39-bit" 1570 depends on PAGE_SIZE_4KB 1571 1572config ARM64_VA_BITS_42 1573 bool "42-bit" 1574 depends on PAGE_SIZE_64KB 1575 1576config ARM64_VA_BITS_47 1577 bool "47-bit" 1578 depends on PAGE_SIZE_16KB 1579 1580config ARM64_VA_BITS_48 1581 bool "48-bit" 1582 1583config ARM64_VA_BITS_52 1584 bool "52-bit" 1585 help 1586 Enable 52-bit virtual addressing for userspace when explicitly 1587 requested via a hint to mmap(). The kernel will also use 52-bit 1588 virtual addresses for its own mappings (provided HW support for 1589 this feature is available, otherwise it reverts to 48-bit). 1590 1591 NOTE: Enabling 52-bit virtual addressing in conjunction with 1592 ARMv8.3 Pointer Authentication will result in the PAC being 1593 reduced from 7 bits to 3 bits, which may have a significant 1594 impact on its susceptibility to brute-force attacks. 1595 1596 If unsure, select 48-bit virtual addressing instead. 1597 1598endchoice 1599 1600config ARM64_FORCE_52BIT 1601 bool "Force 52-bit virtual addresses for userspace" 1602 depends on ARM64_VA_BITS_52 && EXPERT 1603 help 1604 For systems with 52-bit userspace VAs enabled, the kernel will attempt 1605 to maintain compatibility with older software by providing 48-bit VAs 1606 unless a hint is supplied to mmap. 1607 1608 This configuration option disables the 48-bit compatibility logic, and 1609 forces all userspace addresses to be 52-bit on HW that supports it. One 1610 should only enable this configuration option for stress testing userspace 1611 memory management code. If unsure say N here. 1612 1613config ARM64_VA_BITS 1614 int 1615 default 36 if ARM64_VA_BITS_36 1616 default 39 if ARM64_VA_BITS_39 1617 default 42 if ARM64_VA_BITS_42 1618 default 47 if ARM64_VA_BITS_47 1619 default 48 if ARM64_VA_BITS_48 1620 default 52 if ARM64_VA_BITS_52 1621 1622choice 1623 prompt "Physical address space size" 1624 default ARM64_PA_BITS_48 1625 help 1626 Choose the maximum physical address range that the kernel will 1627 support. 1628 1629config ARM64_PA_BITS_48 1630 bool "48-bit" 1631 depends on ARM64_64K_PAGES || !ARM64_VA_BITS_52 1632 1633config ARM64_PA_BITS_52 1634 bool "52-bit" 1635 depends on ARM64_64K_PAGES || ARM64_VA_BITS_52 1636 help 1637 Enable support for a 52-bit physical address space, introduced as 1638 part of the ARMv8.2-LPA extension. 1639 1640 With this enabled, the kernel will also continue to work on CPUs that 1641 do not support ARMv8.2-LPA, but with some added memory overhead (and 1642 minor performance overhead). 1643 1644endchoice 1645 1646config ARM64_PA_BITS 1647 int 1648 default 48 if ARM64_PA_BITS_48 1649 default 52 if ARM64_PA_BITS_52 1650 1651config ARM64_LPA2 1652 def_bool y 1653 depends on ARM64_PA_BITS_52 && !ARM64_64K_PAGES 1654 1655config NR_CPUS 1656 int "Maximum number of CPUs (2-4096)" 1657 range 2 4096 1658 default "512" 1659 1660config HOTPLUG_CPU 1661 bool "Support for hot-pluggable CPUs" 1662 select GENERIC_IRQ_MIGRATION 1663 help 1664 Say Y here to experiment with turning CPUs off and on. CPUs 1665 can be controlled through /sys/devices/system/cpu. 1666 1667# Common NUMA Features 1668config NUMA 1669 bool "NUMA Memory Allocation and Scheduler Support" 1670 select GENERIC_ARCH_NUMA 1671 select OF_NUMA 1672 select HAVE_SETUP_PER_CPU_AREA 1673 select NEED_PER_CPU_EMBED_FIRST_CHUNK 1674 select NEED_PER_CPU_PAGE_FIRST_CHUNK 1675 select USE_PERCPU_NUMA_NODE_ID 1676 help 1677 Enable NUMA (Non-Uniform Memory Access) support. 1678 1679 The kernel will try to allocate memory used by a CPU on the 1680 local memory of the CPU and add some more 1681 NUMA awareness to the kernel. 1682 1683config NODES_SHIFT 1684 int "Maximum NUMA Nodes (as a power of 2)" 1685 range 1 10 1686 default "4" 1687 depends on NUMA 1688 help 1689 Specify the maximum number of NUMA Nodes available on the target 1690 system. Increases memory reserved to accommodate various tables. 1691 1692source "kernel/Kconfig.hz" 1693 1694config ARCH_SPARSEMEM_ENABLE 1695 def_bool y 1696 select SPARSEMEM_VMEMMAP_ENABLE 1697 1698config HW_PERF_EVENTS 1699 def_bool y 1700 depends on ARM_PMU 1701 1702# Supported by clang >= 7.0 or GCC >= 12.0.0 1703config CC_HAVE_SHADOW_CALL_STACK 1704 def_bool $(cc-option, -fsanitize=shadow-call-stack -ffixed-x18) 1705 1706config PARAVIRT 1707 bool "Enable paravirtualization code" 1708 select HAVE_PV_STEAL_CLOCK_GEN 1709 help 1710 This changes the kernel so it can modify itself when it is run 1711 under a hypervisor, potentially improving performance significantly 1712 over full virtualization. 1713 1714config PARAVIRT_TIME_ACCOUNTING 1715 bool "Paravirtual steal time accounting" 1716 select PARAVIRT 1717 help 1718 Select this option to enable fine granularity task steal time 1719 accounting. Time spent executing other tasks in parallel with 1720 the current vCPU is discounted from the vCPU power. To account for 1721 that, there can be a small performance impact. 1722 1723 If in doubt, say N here. 1724 1725config ARCH_SUPPORTS_KEXEC 1726 def_bool PM_SLEEP_SMP 1727 1728config ARCH_SUPPORTS_KEXEC_FILE 1729 def_bool y 1730 1731config ARCH_SELECTS_KEXEC_FILE 1732 def_bool y 1733 depends on KEXEC_FILE 1734 select HAVE_IMA_KEXEC if IMA 1735 1736config ARCH_SUPPORTS_KEXEC_SIG 1737 def_bool y 1738 1739config ARCH_SUPPORTS_KEXEC_IMAGE_VERIFY_SIG 1740 def_bool y 1741 1742config ARCH_DEFAULT_KEXEC_IMAGE_VERIFY_SIG 1743 def_bool y 1744 1745config ARCH_SUPPORTS_KEXEC_HANDOVER 1746 def_bool y 1747 1748config ARCH_SUPPORTS_CRASH_DUMP 1749 def_bool y 1750 1751config ARCH_DEFAULT_CRASH_DUMP 1752 def_bool y 1753 1754config ARCH_HAS_GENERIC_CRASHKERNEL_RESERVATION 1755 def_bool CRASH_RESERVE 1756 1757config TRANS_TABLE 1758 def_bool y 1759 depends on HIBERNATION || KEXEC_CORE 1760 1761config XEN_DOM0 1762 def_bool y 1763 depends on XEN 1764 1765config XEN 1766 bool "Xen guest support on ARM64" 1767 depends on ARM64 && OF 1768 select SWIOTLB_XEN 1769 select PARAVIRT 1770 help 1771 Say Y if you want to run Linux in a Virtual Machine on Xen on ARM64. 1772 1773# include/linux/mmzone.h requires the following to be true: 1774# 1775# MAX_PAGE_ORDER + PAGE_SHIFT <= SECTION_SIZE_BITS 1776# 1777# so the maximum value of MAX_PAGE_ORDER is SECTION_SIZE_BITS - PAGE_SHIFT: 1778# 1779# | SECTION_SIZE_BITS | PAGE_SHIFT | max MAX_PAGE_ORDER | default MAX_PAGE_ORDER | 1780# ----+-------------------+--------------+----------------------+-------------------------+ 1781# 4K | 27 | 12 | 15 | 10 | 1782# 16K | 27 | 14 | 13 | 11 | 1783# 64K | 29 | 16 | 13 | 13 | 1784config ARCH_FORCE_MAX_ORDER 1785 int 1786 default "13" if ARM64_64K_PAGES 1787 default "11" if ARM64_16K_PAGES 1788 default "10" 1789 help 1790 The kernel page allocator limits the size of maximal physically 1791 contiguous allocations. The limit is called MAX_PAGE_ORDER and it 1792 defines the maximal power of two of number of pages that can be 1793 allocated as a single contiguous block. This option allows 1794 overriding the default setting when ability to allocate very 1795 large blocks of physically contiguous memory is required. 1796 1797 The maximal size of allocation cannot exceed the size of the 1798 section, so the value of MAX_PAGE_ORDER should satisfy 1799 1800 MAX_PAGE_ORDER + PAGE_SHIFT <= SECTION_SIZE_BITS 1801 1802 Don't change if unsure. 1803 1804config UNMAP_KERNEL_AT_EL0 1805 bool "Unmap kernel when running in userspace (KPTI)" if EXPERT 1806 default y 1807 help 1808 Speculation attacks against some high-performance processors can 1809 be used to bypass MMU permission checks and leak kernel data to 1810 userspace. This can be defended against by unmapping the kernel 1811 when running in userspace, mapping it back in on exception entry 1812 via a trampoline page in the vector table. 1813 1814 If unsure, say Y. 1815 1816config MITIGATE_SPECTRE_BRANCH_HISTORY 1817 bool "Mitigate Spectre style attacks against branch history" if EXPERT 1818 default y 1819 help 1820 Speculation attacks against some high-performance processors can 1821 make use of branch history to influence future speculation. 1822 When taking an exception from user-space, a sequence of branches 1823 or a firmware call overwrites the branch history. 1824 1825config ARM64_SW_TTBR0_PAN 1826 bool "Emulate Privileged Access Never using TTBR0_EL1 switching" 1827 depends on !KCSAN 1828 help 1829 Enabling this option prevents the kernel from accessing 1830 user-space memory directly by pointing TTBR0_EL1 to a reserved 1831 zeroed area and reserved ASID. The user access routines 1832 restore the valid TTBR0_EL1 temporarily. 1833 1834config ARM64_TAGGED_ADDR_ABI 1835 bool "Enable the tagged user addresses syscall ABI" 1836 default y 1837 help 1838 When this option is enabled, user applications can opt in to a 1839 relaxed ABI via prctl() allowing tagged addresses to be passed 1840 to system calls as pointer arguments. For details, see 1841 Documentation/arch/arm64/tagged-address-abi.rst. 1842 1843menuconfig COMPAT 1844 bool "Kernel support for 32-bit EL0" 1845 depends on ARM64_4K_PAGES || EXPERT 1846 select HAVE_UID16 1847 select OLD_SIGSUSPEND3 1848 select COMPAT_OLD_SIGACTION 1849 help 1850 This option enables support for a 32-bit EL0 running under a 64-bit 1851 kernel at EL1. AArch32-specific components such as system calls, 1852 the user helper functions, VFP support and the ptrace interface are 1853 handled appropriately by the kernel. 1854 1855 If you use a page size other than 4KB (i.e, 16KB or 64KB), please be aware 1856 that you will only be able to execute AArch32 binaries that were compiled 1857 with page size aligned segments. 1858 1859 If you want to execute 32-bit userspace applications, say Y. 1860 1861if COMPAT 1862 1863config KUSER_HELPERS 1864 bool "Enable kuser helpers page for 32-bit applications" 1865 default y 1866 help 1867 Warning: disabling this option may break 32-bit user programs. 1868 1869 Provide kuser helpers to compat tasks. The kernel provides 1870 helper code to userspace in read only form at a fixed location 1871 to allow userspace to be independent of the CPU type fitted to 1872 the system. This permits binaries to be run on ARMv4 through 1873 to ARMv8 without modification. 1874 1875 See Documentation/arch/arm/kernel_user_helpers.rst for details. 1876 1877 However, the fixed address nature of these helpers can be used 1878 by ROP (return orientated programming) authors when creating 1879 exploits. 1880 1881 If all of the binaries and libraries which run on your platform 1882 are built specifically for your platform, and make no use of 1883 these helpers, then you can turn this option off to hinder 1884 such exploits. However, in that case, if a binary or library 1885 relying on those helpers is run, it will not function correctly. 1886 1887 Say N here only if you are absolutely certain that you do not 1888 need these helpers; otherwise, the safe option is to say Y. 1889 1890config COMPAT_VDSO 1891 bool "Enable vDSO for 32-bit applications" 1892 depends on (CC_IS_CLANG && LD_IS_LLD) || "$(CROSS_COMPILE_COMPAT)" != "" 1893 default y 1894 help 1895 Place in the process address space of 32-bit applications an 1896 ELF shared object providing fast implementations of gettimeofday 1897 and clock_gettime. 1898 1899 You must have a 32-bit build of glibc 2.22 or later for programs 1900 to seamlessly take advantage of this. 1901 1902config THUMB2_COMPAT_VDSO 1903 bool "Compile the 32-bit vDSO for Thumb-2 mode" if EXPERT 1904 depends on COMPAT_VDSO 1905 default y 1906 help 1907 Compile the compat vDSO with '-mthumb -fomit-frame-pointer' if y, 1908 otherwise with '-marm'. 1909 1910config COMPAT_ALIGNMENT_FIXUPS 1911 bool "Fix up misaligned multi-word loads and stores in user space" 1912 1913menuconfig ARMV8_DEPRECATED 1914 bool "Emulate deprecated/obsolete ARMv8 instructions" 1915 depends on SYSCTL 1916 help 1917 Legacy software support may require certain instructions 1918 that have been deprecated or obsoleted in the architecture. 1919 1920 Enable this config to enable selective emulation of these 1921 features. 1922 1923 If unsure, say Y 1924 1925if ARMV8_DEPRECATED 1926 1927config SWP_EMULATION 1928 bool "Emulate SWP/SWPB instructions" 1929 help 1930 ARMv8 obsoletes the use of A32 SWP/SWPB instructions such that 1931 they are always undefined. Say Y here to enable software 1932 emulation of these instructions for userspace using LDXR/STXR. 1933 This feature can be controlled at runtime with the abi.swp 1934 sysctl which is disabled by default. 1935 1936 In some older versions of glibc [<=2.8] SWP is used during futex 1937 trylock() operations with the assumption that the code will not 1938 be preempted. This invalid assumption may be more likely to fail 1939 with SWP emulation enabled, leading to deadlock of the user 1940 application. 1941 1942 NOTE: when accessing uncached shared regions, LDXR/STXR rely 1943 on an external transaction monitoring block called a global 1944 monitor to maintain update atomicity. If your system does not 1945 implement a global monitor, this option can cause programs that 1946 perform SWP operations to uncached memory to deadlock. 1947 1948 If unsure, say Y 1949 1950config CP15_BARRIER_EMULATION 1951 bool "Emulate CP15 Barrier instructions" 1952 help 1953 The CP15 barrier instructions - CP15ISB, CP15DSB, and 1954 CP15DMB - are deprecated in ARMv8 (and ARMv7). It is 1955 strongly recommended to use the ISB, DSB, and DMB 1956 instructions instead. 1957 1958 Say Y here to enable software emulation of these 1959 instructions for AArch32 userspace code. When this option is 1960 enabled, CP15 barrier usage is traced which can help 1961 identify software that needs updating. This feature can be 1962 controlled at runtime with the abi.cp15_barrier sysctl. 1963 1964 If unsure, say Y 1965 1966config SETEND_EMULATION 1967 bool "Emulate SETEND instruction" 1968 help 1969 The SETEND instruction alters the data-endianness of the 1970 AArch32 EL0, and is deprecated in ARMv8. 1971 1972 Say Y here to enable software emulation of the instruction 1973 for AArch32 userspace code. This feature can be controlled 1974 at runtime with the abi.setend sysctl. 1975 1976 Note: All the cpus on the system must have mixed endian support at EL0 1977 for this feature to be enabled. If a new CPU - which doesn't support mixed 1978 endian - is hotplugged in after this feature has been enabled, there could 1979 be unexpected results in the applications. 1980 1981 If unsure, say Y 1982endif # ARMV8_DEPRECATED 1983 1984endif # COMPAT 1985 1986menu "ARMv8.1 architectural features" 1987 1988config ARM64_HW_AFDBM 1989 bool "Support for hardware updates of the Access and Dirty page flags" 1990 default y 1991 help 1992 The ARMv8.1 architecture extensions introduce support for 1993 hardware updates of the access and dirty information in page 1994 table entries. When enabled in TCR_EL1 (HA and HD bits) on 1995 capable processors, accesses to pages with PTE_AF cleared will 1996 set this bit instead of raising an access flag fault. 1997 Similarly, writes to read-only pages with the DBM bit set will 1998 clear the read-only bit (AP[2]) instead of raising a 1999 permission fault. 2000 2001 Kernels built with this configuration option enabled continue 2002 to work on pre-ARMv8.1 hardware and the performance impact is 2003 minimal. If unsure, say Y. 2004 2005endmenu # "ARMv8.1 architectural features" 2006 2007menu "ARMv8.2 architectural features" 2008 2009config ARM64_PMEM 2010 bool "Enable support for persistent memory" 2011 select ARCH_HAS_PMEM_API 2012 select ARCH_HAS_UACCESS_FLUSHCACHE 2013 help 2014 Say Y to enable support for the persistent memory API based on the 2015 ARMv8.2 DCPoP feature. 2016 2017 The feature is detected at runtime, and the kernel will use DC CVAC 2018 operations if DC CVAP is not supported (following the behaviour of 2019 DC CVAP itself if the system does not define a point of persistence). 2020 2021config ARM64_RAS_EXTN 2022 bool "Enable support for RAS CPU Extensions" 2023 default y 2024 help 2025 CPUs that support the Reliability, Availability and Serviceability 2026 (RAS) Extensions, part of ARMv8.2 are able to track faults and 2027 errors, classify them and report them to software. 2028 2029 On CPUs with these extensions system software can use additional 2030 barriers to determine if faults are pending and read the 2031 classification from a new set of registers. 2032 2033 Selecting this feature will allow the kernel to use these barriers 2034 and access the new registers if the system supports the extension. 2035 Platform RAS features may additionally depend on firmware support. 2036 2037config ARM64_CNP 2038 bool "Enable support for Common Not Private (CNP) translations" 2039 default y 2040 help 2041 Common Not Private (CNP) allows translation table entries to 2042 be shared between different PEs in the same inner shareable 2043 domain, so the hardware can use this fact to optimise the 2044 caching of such entries in the TLB. 2045 2046 Selecting this option allows the CNP feature to be detected 2047 at runtime, and does not affect PEs that do not implement 2048 this feature. 2049 2050endmenu # "ARMv8.2 architectural features" 2051 2052menu "ARMv8.3 architectural features" 2053 2054config ARM64_PTR_AUTH 2055 bool "Enable support for pointer authentication" 2056 default y 2057 help 2058 Pointer authentication (part of the ARMv8.3 Extensions) provides 2059 instructions for signing and authenticating pointers against secret 2060 keys, which can be used to mitigate Return Oriented Programming (ROP) 2061 and other attacks. 2062 2063 This option enables these instructions at EL0 (i.e. for userspace). 2064 Choosing this option will cause the kernel to initialise secret keys 2065 for each process at exec() time, with these keys being 2066 context-switched along with the process. 2067 2068 The feature is detected at runtime. If the feature is not present in 2069 hardware it will not be advertised to userspace/KVM guest nor will it 2070 be enabled. 2071 2072 If the feature is present on the boot CPU but not on a late CPU, then 2073 the late CPU will be parked. Also, if the boot CPU does not have 2074 address auth and the late CPU has then the late CPU will still boot 2075 but with the feature disabled. On such a system, this option should 2076 not be selected. 2077 2078config ARM64_PTR_AUTH_KERNEL 2079 bool "Use pointer authentication for kernel" 2080 default y 2081 depends on ARM64_PTR_AUTH 2082 # Modern compilers insert a .note.gnu.property section note for PAC 2083 # which is only understood by binutils starting with version 2.33.1. 2084 depends on LD_IS_LLD || LD_VERSION >= 23301 || (CC_IS_GCC && GCC_VERSION < 90100) 2085 depends on !CC_IS_CLANG || AS_HAS_CFI_NEGATE_RA_STATE 2086 depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_ARGS) 2087 help 2088 If the compiler supports the -mbranch-protection or 2089 -msign-return-address flag (e.g. GCC 7 or later), then this option 2090 will cause the kernel itself to be compiled with return address 2091 protection. In this case, and if the target hardware is known to 2092 support pointer authentication, then CONFIG_STACKPROTECTOR can be 2093 disabled with minimal loss of protection. 2094 2095 This feature works with FUNCTION_GRAPH_TRACER option only if 2096 DYNAMIC_FTRACE_WITH_ARGS is enabled. 2097 2098config CC_HAS_BRANCH_PROT_PAC_RET 2099 # GCC 9 or later, clang 8 or later 2100 def_bool $(cc-option,-mbranch-protection=pac-ret+leaf) 2101 2102config AS_HAS_CFI_NEGATE_RA_STATE 2103 # binutils 2.34+ 2104 def_bool $(as-instr,.cfi_startproc\n.cfi_negate_ra_state\n.cfi_endproc\n) 2105 2106endmenu # "ARMv8.3 architectural features" 2107 2108menu "ARMv8.4 architectural features" 2109 2110config ARM64_AMU_EXTN 2111 bool "Enable support for the Activity Monitors Unit CPU extension" 2112 default y 2113 help 2114 The activity monitors extension is an optional extension introduced 2115 by the ARMv8.4 CPU architecture. This enables support for version 1 2116 of the activity monitors architecture, AMUv1. 2117 2118 To enable the use of this extension on CPUs that implement it, say Y. 2119 2120 Note that for architectural reasons, firmware _must_ implement AMU 2121 support when running on CPUs that present the activity monitors 2122 extension. The required support is present in: 2123 * Version 1.5 and later of the ARM Trusted Firmware 2124 2125 For kernels that have this configuration enabled but boot with broken 2126 firmware, you may need to say N here until the firmware is fixed. 2127 Otherwise you may experience firmware panics or lockups when 2128 accessing the counter registers. Even if you are not observing these 2129 symptoms, the values returned by the register reads might not 2130 correctly reflect reality. Most commonly, the value read will be 0, 2131 indicating that the counter is not enabled. 2132 2133config ARM64_TLB_RANGE 2134 bool "Enable support for tlbi range feature" 2135 default y 2136 help 2137 ARMv8.4-TLBI provides TLBI invalidation instruction that apply to a 2138 range of input addresses. 2139 2140config ARM64_MPAM 2141 bool "Enable support for MPAM" 2142 select ARM64_MPAM_DRIVER 2143 select ARCH_HAS_CPU_RESCTRL 2144 help 2145 Memory System Resource Partitioning and Monitoring (MPAM) is an 2146 optional extension to the Arm architecture that allows each 2147 transaction issued to the memory system to be labelled with a 2148 Partition identifier (PARTID) and Performance Monitoring Group 2149 identifier (PMG). 2150 2151 Memory system components, such as the caches, can be configured with 2152 policies to control how much of various physical resources (such as 2153 memory bandwidth or cache memory) the transactions labelled with each 2154 PARTID can consume. Depending on the capabilities of the hardware, 2155 the PARTID and PMG can also be used as filtering criteria to measure 2156 the memory system resource consumption of different parts of a 2157 workload. 2158 2159 Use of this extension requires CPU support, support in the 2160 Memory System Components (MSC), and a description from firmware 2161 of where the MSCs are in the address space. 2162 2163 MPAM is exposed to user-space via the resctrl pseudo filesystem. 2164 2165 This option enables the extra context switch code. 2166 2167endmenu # "ARMv8.4 architectural features" 2168 2169menu "ARMv8.5 architectural features" 2170 2171config AS_HAS_ARMV8_5 2172 def_bool $(cc-option,-Wa$(comma)-march=armv8.5-a) 2173 2174config ARM64_BTI 2175 bool "Branch Target Identification support" 2176 default y 2177 help 2178 Branch Target Identification (part of the ARMv8.5 Extensions) 2179 provides a mechanism to limit the set of locations to which computed 2180 branch instructions such as BR or BLR can jump. 2181 2182 To make use of BTI on CPUs that support it, say Y. 2183 2184 BTI is intended to provide complementary protection to other control 2185 flow integrity protection mechanisms, such as the Pointer 2186 authentication mechanism provided as part of the ARMv8.3 Extensions. 2187 For this reason, it does not make sense to enable this option without 2188 also enabling support for pointer authentication. Thus, when 2189 enabling this option you should also select ARM64_PTR_AUTH=y. 2190 2191 Userspace binaries must also be specifically compiled to make use of 2192 this mechanism. If you say N here or the hardware does not support 2193 BTI, such binaries can still run, but you get no additional 2194 enforcement of branch destinations. 2195 2196config ARM64_BTI_KERNEL 2197 bool "Use Branch Target Identification for kernel" 2198 default y 2199 depends on ARM64_BTI 2200 depends on ARM64_PTR_AUTH_KERNEL 2201 depends on CC_HAS_BRANCH_PROT_PAC_RET_BTI 2202 # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94697 2203 depends on !CC_IS_GCC || GCC_VERSION >= 100100 2204 # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106671 2205 depends on !CC_IS_GCC 2206 # https://github.com/llvm/llvm-project/issues/215547 2207 depends on !CC_IS_CLANG || CLANG_VERSION < 210000 2208 depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_ARGS) 2209 help 2210 Build the kernel with Branch Target Identification annotations 2211 and enable enforcement of this for kernel code. When this option 2212 is enabled and the system supports BTI all kernel code including 2213 modular code must have BTI enabled. 2214 2215config CC_HAS_BRANCH_PROT_PAC_RET_BTI 2216 # GCC 9 or later, clang 8 or later 2217 def_bool $(cc-option,-mbranch-protection=pac-ret+leaf+bti) 2218 2219config ARM64_E0PD 2220 bool "Enable support for E0PD" 2221 default y 2222 help 2223 E0PD (part of the ARMv8.5 extensions) allows us to ensure 2224 that EL0 accesses made via TTBR1 always fault in constant time, 2225 providing similar benefits to KASLR as those provided by KPTI, but 2226 with lower overhead and without disrupting legitimate access to 2227 kernel memory such as SPE. 2228 2229 This option enables E0PD for TTBR1 where available. 2230 2231config ARM64_AS_HAS_MTE 2232 # Initial support for MTE went in binutils 2.32.0, checked with 2233 # ".arch armv8.5-a+memtag" below. However, this was incomplete 2234 # as a late addition to the final architecture spec (LDGM/STGM) 2235 # is only supported in the newer 2.32.x and 2.33 binutils 2236 # versions, hence the extra "stgm" instruction check below. 2237 def_bool $(as-instr,.arch armv8.5-a+memtag\nstgm xzr$(comma)[x0]) 2238 2239config ARM64_MTE 2240 bool "Memory Tagging Extension support" 2241 default y 2242 depends on ARM64_AS_HAS_MTE && ARM64_TAGGED_ADDR_ABI 2243 depends on AS_HAS_ARMV8_5 2244 # Required for tag checking in the uaccess routines 2245 select ARCH_HAS_SUBPAGE_FAULTS 2246 select ARCH_USES_HIGH_VMA_FLAGS 2247 select ARCH_USES_PG_ARCH_2 2248 select ARCH_USES_PG_ARCH_3 2249 help 2250 Memory Tagging (part of the ARMv8.5 Extensions) provides 2251 architectural support for run-time, always-on detection of 2252 various classes of memory error to aid with software debugging 2253 to eliminate vulnerabilities arising from memory-unsafe 2254 languages. 2255 2256 This option enables the support for the Memory Tagging 2257 Extension at EL0 (i.e. for userspace). 2258 2259 Selecting this option allows the feature to be detected at 2260 runtime. Any secondary CPU not implementing this feature will 2261 not be allowed a late bring-up. 2262 2263 Userspace binaries that want to use this feature must 2264 explicitly opt in. The mechanism for the userspace is 2265 described in: 2266 2267 Documentation/arch/arm64/memory-tagging-extension.rst. 2268 2269endmenu # "ARMv8.5 architectural features" 2270 2271menu "ARMv8.7 architectural features" 2272 2273config ARM64_EPAN 2274 bool "Enable support for Enhanced Privileged Access Never (EPAN)" 2275 default y 2276 help 2277 Enhanced Privileged Access Never (EPAN) allows Privileged 2278 Access Never to be used with Execute-only mappings. 2279 2280 The feature is detected at runtime, and will remain disabled 2281 if the cpu does not implement the feature. 2282endmenu # "ARMv8.7 architectural features" 2283 2284config AS_HAS_MOPS 2285 def_bool $(as-instr,.arch_extension mops) 2286 2287menu "ARMv8.9 architectural features" 2288 2289config ARM64_POE 2290 prompt "Permission Overlay Extension" 2291 def_bool y 2292 select ARCH_USES_HIGH_VMA_FLAGS 2293 select ARCH_HAS_PKEYS 2294 help 2295 The Permission Overlay Extension is used to implement Memory 2296 Protection Keys. Memory Protection Keys provides a mechanism for 2297 enforcing page-based protections, but without requiring modification 2298 of the page tables when an application changes protection domains. 2299 2300 For details, see Documentation/core-api/protection-keys.rst 2301 2302 If unsure, say y. 2303 2304config ARCH_PKEY_BITS 2305 int 2306 default 3 2307 2308config ARM64_HAFT 2309 bool "Support for Hardware managed Access Flag for Table Descriptors" 2310 depends on ARM64_HW_AFDBM 2311 default y 2312 help 2313 The ARMv8.9/ARMv9.5 introduces the feature Hardware managed Access 2314 Flag for Table descriptors. When enabled an architectural executed 2315 memory access will update the Access Flag in each Table descriptor 2316 which is accessed during the translation table walk and for which 2317 the Access Flag is 0. The Access Flag of the Table descriptor use 2318 the same bit of PTE_AF. 2319 2320 The feature will only be enabled if all the CPUs in the system 2321 support this feature. If unsure, say Y. 2322 2323endmenu # "ARMv8.9 architectural features" 2324 2325menu "ARMv9.4 architectural features" 2326 2327config ARM64_GCS 2328 bool "Enable support for Guarded Control Stack (GCS)" 2329 default y 2330 select ARCH_HAS_USER_SHADOW_STACK 2331 select ARCH_USES_HIGH_VMA_FLAGS 2332 help 2333 Guarded Control Stack (GCS) provides support for a separate 2334 stack with restricted access which contains only return 2335 addresses. This can be used to harden against some attacks 2336 by comparing return address used by the program with what is 2337 stored in the GCS, and may also be used to efficiently obtain 2338 the call stack for applications such as profiling. 2339 2340 The feature is detected at runtime, and will remain disabled 2341 if the system does not implement the feature. 2342 2343endmenu # "ARMv9.4 architectural features" 2344 2345config AS_HAS_LSUI 2346 def_bool $(as-instr,.arch_extension lsui) 2347 help 2348 Supported by LLVM 20+ and binutils 2.45+. 2349 2350menu "ARMv9.6 architectural features" 2351 2352config ARM64_LSUI 2353 bool "Support Unprivileged Load Store Instructions (LSUI)" 2354 default y 2355 depends on AS_HAS_LSUI 2356 help 2357 The Unprivileged Load Store Instructions (LSUI) provides 2358 variants load/store instructions that access user-space memory 2359 from the kernel without clearing PSTATE.PAN bit. 2360 2361 This feature is supported by LLVM 20+ and binutils 2.45+. 2362 2363endmenu # "ARMv9.6 architectural feature" 2364 2365config ARM64_SVE 2366 bool "ARM Scalable Vector Extension support" 2367 default y 2368 help 2369 The Scalable Vector Extension (SVE) is an extension to the AArch64 2370 execution state which complements and extends the SIMD functionality 2371 of the base architecture to support much larger vectors and to enable 2372 additional vectorisation opportunities. 2373 2374 To enable use of this extension on CPUs that implement it, say Y. 2375 2376 On CPUs that support the SVE2 extensions, this option will enable 2377 those too. 2378 2379 Note that for architectural reasons, firmware _must_ implement SVE 2380 support when running on SVE capable hardware. The required support 2381 is present in: 2382 2383 * version 1.5 and later of the ARM Trusted Firmware 2384 * the AArch64 boot wrapper since commit 5e1261e08abf 2385 ("bootwrapper: SVE: Enable SVE for EL2 and below"). 2386 2387 For other firmware implementations, consult the firmware documentation 2388 or vendor. 2389 2390 If you need the kernel to boot on SVE-capable hardware with broken 2391 firmware, you may need to say N here until you get your firmware 2392 fixed. Otherwise, you may experience firmware panics or lockups when 2393 booting the kernel. If unsure and you are not observing these 2394 symptoms, you should assume that it is safe to say Y. 2395 2396config AS_HAS_SME 2397 # Supported by LLVM 13+ and binutils 2.38+ 2398 def_bool $(as-instr,.arch_extension sme) 2399 2400config ARM64_SME 2401 bool "ARM Scalable Matrix Extension support" 2402 default y 2403 depends on ARM64_SVE 2404 depends on AS_HAS_SME 2405 help 2406 The Scalable Matrix Extension (SME) is an extension to the AArch64 2407 execution state which utilises a substantial subset of the SVE 2408 instruction set, together with the addition of new architectural 2409 register state capable of holding two dimensional matrix tiles to 2410 enable various matrix operations. 2411 2412config ARM64_PSEUDO_NMI 2413 bool "Support for NMI-like interrupts" 2414 select ARM_GIC_V3 2415 help 2416 Adds support for mimicking Non-Maskable Interrupts through the use of 2417 GIC interrupt priority. This support requires version 3 or later of 2418 ARM GIC. 2419 2420 This high priority configuration for interrupts needs to be 2421 explicitly enabled by setting the kernel parameter 2422 "irqchip.gicv3_pseudo_nmi" to 1. 2423 2424 If unsure, say N 2425 2426if ARM64_PSEUDO_NMI 2427config ARM64_DEBUG_PRIORITY_MASKING 2428 bool "Debug interrupt priority masking" 2429 help 2430 This adds runtime checks to functions enabling/disabling 2431 interrupts when using priority masking. The additional checks verify 2432 the validity of ICC_PMR_EL1 when calling concerned functions. 2433 2434 If unsure, say N 2435endif # ARM64_PSEUDO_NMI 2436 2437config RELOCATABLE 2438 bool "Build a relocatable kernel image" if EXPERT 2439 select ARCH_HAS_RELR 2440 default y 2441 help 2442 This builds the kernel as a Position Independent Executable (PIE), 2443 which retains all relocation metadata required to relocate the 2444 kernel binary at runtime to a different virtual address than the 2445 address it was linked at. 2446 Since AArch64 uses the RELA relocation format, this requires a 2447 relocation pass at runtime even if the kernel is loaded at the 2448 same address it was linked at. 2449 2450config RANDOMIZE_BASE 2451 bool "Randomize the address of the kernel image" 2452 select RELOCATABLE 2453 help 2454 Randomizes the virtual address at which the kernel image is 2455 loaded, as a security feature that deters exploit attempts 2456 relying on knowledge of the location of kernel internals. 2457 2458 It is the bootloader's job to provide entropy, by passing a 2459 random u64 value in /chosen/kaslr-seed at kernel entry. 2460 2461 When booting via the UEFI stub, it will invoke the firmware's 2462 EFI_RNG_PROTOCOL implementation (if available) to supply entropy 2463 to the kernel proper. In addition, it will randomise the physical 2464 location of the kernel Image as well. 2465 2466 If unsure, say N. 2467 2468config RANDOMIZE_MODULE_REGION_FULL 2469 bool "Randomize the module region over a 2 GB range" 2470 depends on RANDOMIZE_BASE 2471 default y 2472 help 2473 Randomizes the location of the module region inside a 2 GB window 2474 covering the core kernel. This way, it is less likely for modules 2475 to leak information about the location of core kernel data structures 2476 but it does imply that function calls between modules and the core 2477 kernel will need to be resolved via veneers in the module PLT. 2478 2479 When this option is not set, the module region will be randomized over 2480 a limited range that contains the [_stext, _etext] interval of the 2481 core kernel, so branch relocations are almost always in range unless 2482 the region is exhausted. In this particular case of region 2483 exhaustion, modules might be able to fall back to a larger 2GB area. 2484 2485config CC_HAVE_STACKPROTECTOR_SYSREG 2486 def_bool $(cc-option,-mstack-protector-guard=sysreg -mstack-protector-guard-reg=sp_el0 -mstack-protector-guard-offset=0) 2487 2488config STACKPROTECTOR_PER_TASK 2489 def_bool y 2490 depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_SYSREG 2491 2492config UNWIND_PATCH_PAC_INTO_SCS 2493 bool "Enable shadow call stack dynamically using code patching" 2494 depends on CC_IS_CLANG 2495 depends on ARM64_PTR_AUTH_KERNEL && CC_HAS_BRANCH_PROT_PAC_RET 2496 depends on SHADOW_CALL_STACK 2497 select UNWIND_TABLES 2498 select DYNAMIC_SCS 2499 2500config ARM64_CONTPTE 2501 bool "Contiguous PTE mappings for user memory" if EXPERT 2502 depends on TRANSPARENT_HUGEPAGE 2503 default y 2504 help 2505 When enabled, user mappings are configured using the PTE contiguous 2506 bit, for any mappings that meet the size and alignment requirements. 2507 This reduces TLB pressure and improves performance. 2508 2509endmenu # "Kernel Features" 2510 2511menu "Boot options" 2512 2513config ARM64_ACPI_PARKING_PROTOCOL 2514 bool "Enable support for the ARM64 ACPI parking protocol" 2515 depends on ACPI 2516 help 2517 Enable support for the ARM64 ACPI parking protocol. If disabled 2518 the kernel will not allow booting through the ARM64 ACPI parking 2519 protocol even if the corresponding data is present in the ACPI 2520 MADT table. 2521 2522config CMDLINE 2523 string "Default kernel command string" 2524 default "" 2525 help 2526 Provide a set of default command-line options at build time by 2527 entering them here. As a minimum, you should specify the 2528 root device (e.g. root=/dev/nfs). 2529 2530choice 2531 prompt "Kernel command line type" 2532 depends on CMDLINE != "" 2533 default CMDLINE_FROM_BOOTLOADER 2534 help 2535 Choose how the kernel will handle the provided default kernel 2536 command line string. 2537 2538config CMDLINE_FROM_BOOTLOADER 2539 bool "Use bootloader kernel arguments if available" 2540 help 2541 Uses the command-line options passed by the boot loader. If 2542 the boot loader doesn't provide any, the default kernel command 2543 string provided in CMDLINE will be used. 2544 2545config CMDLINE_FORCE 2546 bool "Always use the default kernel command string" 2547 help 2548 Always use the default kernel command string, even if the boot 2549 loader passes other arguments to the kernel. 2550 This is useful if you cannot or don't want to change the 2551 command-line options your boot loader passes to the kernel. 2552 2553endchoice 2554 2555config EFI_STUB 2556 bool 2557 2558config EFI 2559 bool "UEFI runtime support" 2560 depends on OF 2561 depends on KERNEL_MODE_NEON 2562 select ARCH_SUPPORTS_ACPI 2563 select LIBFDT 2564 select UCS2_STRING 2565 select EFI_PARAMS_FROM_FDT 2566 select EFI_RUNTIME_WRAPPERS 2567 select EFI_STUB 2568 select EFI_GENERIC_STUB 2569 imply IMA_SECURE_AND_OR_TRUSTED_BOOT 2570 default y 2571 help 2572 This option provides support for runtime services provided 2573 by UEFI firmware (such as non-volatile variables, realtime 2574 clock, and platform reset). A UEFI stub is also provided to 2575 allow the kernel to be booted as an EFI application. This 2576 is only useful on systems that have UEFI firmware. 2577 2578config COMPRESSED_INSTALL 2579 bool "Install compressed image by default" 2580 help 2581 This makes the regular "make install" install the compressed 2582 image we built, not the legacy uncompressed one. 2583 2584 You can check that a compressed image works for you by doing 2585 "make zinstall" first, and verifying that everything is fine 2586 in your environment before making "make install" do this for 2587 you. 2588 2589config DMI 2590 bool "Enable support for SMBIOS (DMI) tables" 2591 depends on EFI 2592 default y 2593 help 2594 This enables SMBIOS/DMI feature for systems. 2595 2596 This option is only useful on systems that have UEFI firmware. 2597 However, even with this option, the resultant kernel should 2598 continue to boot on existing non-UEFI platforms. 2599 2600endmenu # "Boot options" 2601 2602menu "Power management options" 2603 2604source "kernel/power/Kconfig" 2605 2606config ARCH_HIBERNATION_POSSIBLE 2607 def_bool y 2608 depends on CPU_PM 2609 2610config ARCH_HIBERNATION_HEADER 2611 def_bool y 2612 depends on HIBERNATION 2613 2614config ARCH_SUSPEND_POSSIBLE 2615 def_bool y 2616 2617endmenu # "Power management options" 2618 2619menu "CPU Power Management" 2620 2621source "drivers/cpuidle/Kconfig" 2622 2623source "drivers/cpufreq/Kconfig" 2624 2625endmenu # "CPU Power Management" 2626 2627source "drivers/acpi/Kconfig" 2628 2629source "arch/arm64/kvm/Kconfig" 2630 2631source "kernel/livepatch/Kconfig" 2632