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_IORT if ACPI 9 select ACPI_REDUCED_HARDWARE_ONLY if ACPI 10 select ACPI_MCFG if (ACPI && PCI) 11 select ACPI_SPCR_TABLE if ACPI 12 select ACPI_PPTT if ACPI 13 select ARCH_HAS_DEBUG_WX 14 select ARCH_BINFMT_ELF_EXTRA_PHDRS 15 select ARCH_BINFMT_ELF_STATE 16 select ARCH_CORRECT_STACKTRACE_ON_KRETPROBE 17 select ARCH_ENABLE_HUGEPAGE_MIGRATION if HUGETLB_PAGE && MIGRATION 18 select ARCH_ENABLE_MEMORY_HOTPLUG 19 select ARCH_ENABLE_MEMORY_HOTREMOVE 20 select ARCH_ENABLE_SPLIT_PMD_PTLOCK if PGTABLE_LEVELS > 2 21 select ARCH_ENABLE_THP_MIGRATION if TRANSPARENT_HUGEPAGE 22 select ARCH_HAS_CACHE_LINE_SIZE 23 select ARCH_HAS_CURRENT_STACK_POINTER 24 select ARCH_HAS_DEBUG_VIRTUAL 25 select ARCH_HAS_DEBUG_VM_PGTABLE 26 select ARCH_HAS_DMA_PREP_COHERENT 27 select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI 28 select ARCH_HAS_FAST_MULTIPLIER 29 select ARCH_HAS_FORTIFY_SOURCE 30 select ARCH_HAS_GCOV_PROFILE_ALL 31 select ARCH_HAS_GIGANTIC_PAGE 32 select ARCH_HAS_KCOV 33 select ARCH_HAS_KEEPINITRD 34 select ARCH_HAS_MEMBARRIER_SYNC_CORE 35 select ARCH_HAS_NMI_SAFE_THIS_CPU_OPS 36 select ARCH_HAS_NON_OVERLAPPING_ADDRESS_SPACE 37 select ARCH_HAS_PTE_DEVMAP 38 select ARCH_HAS_PTE_SPECIAL 39 select ARCH_HAS_SETUP_DMA_OPS 40 select ARCH_HAS_SET_DIRECT_MAP 41 select ARCH_HAS_SET_MEMORY 42 select ARCH_STACKWALK 43 select ARCH_HAS_STRICT_KERNEL_RWX 44 select ARCH_HAS_STRICT_MODULE_RWX 45 select ARCH_HAS_SYNC_DMA_FOR_DEVICE 46 select ARCH_HAS_SYNC_DMA_FOR_CPU 47 select ARCH_HAS_SYSCALL_WRAPPER 48 select ARCH_HAS_TEARDOWN_DMA_OPS if IOMMU_SUPPORT 49 select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST 50 select ARCH_HAS_ZONE_DMA_SET if EXPERT 51 select ARCH_HAVE_ELF_PROT 52 select ARCH_HAVE_NMI_SAFE_CMPXCHG 53 select ARCH_HAVE_TRACE_MMIO_ACCESS 54 select ARCH_INLINE_READ_LOCK if !PREEMPTION 55 select ARCH_INLINE_READ_LOCK_BH if !PREEMPTION 56 select ARCH_INLINE_READ_LOCK_IRQ if !PREEMPTION 57 select ARCH_INLINE_READ_LOCK_IRQSAVE if !PREEMPTION 58 select ARCH_INLINE_READ_UNLOCK if !PREEMPTION 59 select ARCH_INLINE_READ_UNLOCK_BH if !PREEMPTION 60 select ARCH_INLINE_READ_UNLOCK_IRQ if !PREEMPTION 61 select ARCH_INLINE_READ_UNLOCK_IRQRESTORE if !PREEMPTION 62 select ARCH_INLINE_WRITE_LOCK if !PREEMPTION 63 select ARCH_INLINE_WRITE_LOCK_BH if !PREEMPTION 64 select ARCH_INLINE_WRITE_LOCK_IRQ if !PREEMPTION 65 select ARCH_INLINE_WRITE_LOCK_IRQSAVE if !PREEMPTION 66 select ARCH_INLINE_WRITE_UNLOCK if !PREEMPTION 67 select ARCH_INLINE_WRITE_UNLOCK_BH if !PREEMPTION 68 select ARCH_INLINE_WRITE_UNLOCK_IRQ if !PREEMPTION 69 select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE if !PREEMPTION 70 select ARCH_INLINE_SPIN_TRYLOCK if !PREEMPTION 71 select ARCH_INLINE_SPIN_TRYLOCK_BH if !PREEMPTION 72 select ARCH_INLINE_SPIN_LOCK if !PREEMPTION 73 select ARCH_INLINE_SPIN_LOCK_BH if !PREEMPTION 74 select ARCH_INLINE_SPIN_LOCK_IRQ if !PREEMPTION 75 select ARCH_INLINE_SPIN_LOCK_IRQSAVE if !PREEMPTION 76 select ARCH_INLINE_SPIN_UNLOCK if !PREEMPTION 77 select ARCH_INLINE_SPIN_UNLOCK_BH if !PREEMPTION 78 select ARCH_INLINE_SPIN_UNLOCK_IRQ if !PREEMPTION 79 select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE if !PREEMPTION 80 select ARCH_KEEP_MEMBLOCK 81 select ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE 82 select ARCH_USE_CMPXCHG_LOCKREF 83 select ARCH_USE_GNU_PROPERTY 84 select ARCH_USE_MEMTEST 85 select ARCH_USE_QUEUED_RWLOCKS 86 select ARCH_USE_QUEUED_SPINLOCKS 87 select ARCH_USE_SYM_ANNOTATIONS 88 select ARCH_SUPPORTS_DEBUG_PAGEALLOC 89 select ARCH_SUPPORTS_HUGETLBFS 90 select ARCH_SUPPORTS_MEMORY_FAILURE 91 select ARCH_SUPPORTS_SHADOW_CALL_STACK if CC_HAVE_SHADOW_CALL_STACK 92 select ARCH_SUPPORTS_LTO_CLANG if CPU_LITTLE_ENDIAN 93 select ARCH_SUPPORTS_LTO_CLANG_THIN 94 select ARCH_SUPPORTS_CFI_CLANG 95 select ARCH_SUPPORTS_ATOMIC_RMW 96 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 97 select ARCH_SUPPORTS_NUMA_BALANCING 98 select ARCH_SUPPORTS_PAGE_TABLE_CHECK 99 select ARCH_SUPPORTS_PER_VMA_LOCK 100 select ARCH_WANT_BATCHED_UNMAP_TLB_FLUSH 101 select ARCH_WANT_COMPAT_IPC_PARSE_VERSION if COMPAT 102 select ARCH_WANT_DEFAULT_BPF_JIT 103 select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT 104 select ARCH_WANT_FRAME_POINTERS 105 select ARCH_WANT_HUGE_PMD_SHARE if ARM64_4K_PAGES || (ARM64_16K_PAGES && !ARM64_VA_BITS_36) 106 select ARCH_WANT_LD_ORPHAN_WARN 107 select ARCH_WANTS_NO_INSTR 108 select ARCH_WANTS_THP_SWAP if ARM64_4K_PAGES 109 select ARCH_HAS_UBSAN_SANITIZE_ALL 110 select ARM_AMBA 111 select ARM_ARCH_TIMER 112 select ARM_GIC 113 select AUDIT_ARCH_COMPAT_GENERIC 114 select ARM_GIC_V2M if PCI 115 select ARM_GIC_V3 116 select ARM_GIC_V3_ITS if PCI 117 select ARM_PSCI_FW 118 select BUILDTIME_TABLE_SORT 119 select CLONE_BACKWARDS 120 select COMMON_CLK 121 select CPU_PM if (SUSPEND || CPU_IDLE) 122 select CRC32 123 select DCACHE_WORD_ACCESS 124 select DYNAMIC_FTRACE if FUNCTION_TRACER 125 select DMA_BOUNCE_UNALIGNED_KMALLOC 126 select DMA_DIRECT_REMAP 127 select EDAC_SUPPORT 128 select FRAME_POINTER 129 select FUNCTION_ALIGNMENT_4B 130 select FUNCTION_ALIGNMENT_8B if DYNAMIC_FTRACE_WITH_CALL_OPS 131 select GENERIC_ALLOCATOR 132 select GENERIC_ARCH_TOPOLOGY 133 select GENERIC_CLOCKEVENTS_BROADCAST 134 select GENERIC_CPU_AUTOPROBE 135 select GENERIC_CPU_VULNERABILITIES 136 select GENERIC_EARLY_IOREMAP 137 select GENERIC_IDLE_POLL_SETUP 138 select GENERIC_IOREMAP 139 select GENERIC_IRQ_IPI 140 select GENERIC_IRQ_PROBE 141 select GENERIC_IRQ_SHOW 142 select GENERIC_IRQ_SHOW_LEVEL 143 select GENERIC_LIB_DEVMEM_IS_ALLOWED 144 select GENERIC_PCI_IOMAP 145 select GENERIC_PTDUMP 146 select GENERIC_SCHED_CLOCK 147 select GENERIC_SMP_IDLE_THREAD 148 select GENERIC_TIME_VSYSCALL 149 select GENERIC_GETTIMEOFDAY 150 select GENERIC_VDSO_TIME_NS 151 select HARDIRQS_SW_RESEND 152 select HAS_IOPORT 153 select HAVE_MOVE_PMD 154 select HAVE_MOVE_PUD 155 select HAVE_PCI 156 select HAVE_ACPI_APEI if (ACPI && EFI) 157 select HAVE_ALIGNED_STRUCT_PAGE if SLUB 158 select HAVE_ARCH_AUDITSYSCALL 159 select HAVE_ARCH_BITREVERSE 160 select HAVE_ARCH_COMPILER_H 161 select HAVE_ARCH_HUGE_VMALLOC 162 select HAVE_ARCH_HUGE_VMAP 163 select HAVE_ARCH_JUMP_LABEL 164 select HAVE_ARCH_JUMP_LABEL_RELATIVE 165 select HAVE_ARCH_KASAN if !(ARM64_16K_PAGES && ARM64_VA_BITS_48) 166 select HAVE_ARCH_KASAN_VMALLOC if HAVE_ARCH_KASAN 167 select HAVE_ARCH_KASAN_SW_TAGS if HAVE_ARCH_KASAN 168 select HAVE_ARCH_KASAN_HW_TAGS if (HAVE_ARCH_KASAN && ARM64_MTE) 169 # Some instrumentation may be unsound, hence EXPERT 170 select HAVE_ARCH_KCSAN if EXPERT 171 select HAVE_ARCH_KFENCE 172 select HAVE_ARCH_KGDB 173 select HAVE_ARCH_MMAP_RND_BITS 174 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT 175 select HAVE_ARCH_PREL32_RELOCATIONS 176 select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET 177 select HAVE_ARCH_SECCOMP_FILTER 178 select HAVE_ARCH_STACKLEAK 179 select HAVE_ARCH_THREAD_STRUCT_WHITELIST 180 select HAVE_ARCH_TRACEHOOK 181 select HAVE_ARCH_TRANSPARENT_HUGEPAGE 182 select HAVE_ARCH_VMAP_STACK 183 select HAVE_ARM_SMCCC 184 select HAVE_ASM_MODVERSIONS 185 select HAVE_EBPF_JIT 186 select HAVE_C_RECORDMCOUNT 187 select HAVE_CMPXCHG_DOUBLE 188 select HAVE_CMPXCHG_LOCAL 189 select HAVE_CONTEXT_TRACKING_USER 190 select HAVE_DEBUG_KMEMLEAK 191 select HAVE_DMA_CONTIGUOUS 192 select HAVE_DYNAMIC_FTRACE 193 select HAVE_DYNAMIC_FTRACE_WITH_ARGS \ 194 if (GCC_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS || \ 195 CLANG_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS) 196 select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS \ 197 if DYNAMIC_FTRACE_WITH_ARGS && DYNAMIC_FTRACE_WITH_CALL_OPS 198 select HAVE_DYNAMIC_FTRACE_WITH_CALL_OPS \ 199 if (DYNAMIC_FTRACE_WITH_ARGS && !CFI_CLANG && \ 200 (CC_IS_CLANG || !CC_OPTIMIZE_FOR_SIZE)) 201 select FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY \ 202 if DYNAMIC_FTRACE_WITH_ARGS 203 select HAVE_SAMPLE_FTRACE_DIRECT 204 select HAVE_SAMPLE_FTRACE_DIRECT_MULTI 205 select HAVE_EFFICIENT_UNALIGNED_ACCESS 206 select HAVE_FAST_GUP 207 select HAVE_FTRACE_MCOUNT_RECORD 208 select HAVE_FUNCTION_TRACER 209 select HAVE_FUNCTION_ERROR_INJECTION 210 select HAVE_FUNCTION_GRAPH_RETVAL if HAVE_FUNCTION_GRAPH_TRACER 211 select HAVE_FUNCTION_GRAPH_TRACER 212 select HAVE_GCC_PLUGINS 213 select HAVE_HARDLOCKUP_DETECTOR_PERF if PERF_EVENTS && \ 214 HW_PERF_EVENTS && HAVE_PERF_EVENTS_NMI 215 select HAVE_HW_BREAKPOINT if PERF_EVENTS 216 select HAVE_IOREMAP_PROT 217 select HAVE_IRQ_TIME_ACCOUNTING 218 select HAVE_KVM 219 select HAVE_MOD_ARCH_SPECIFIC 220 select HAVE_NMI 221 select HAVE_PERF_EVENTS 222 select HAVE_PERF_EVENTS_NMI if ARM64_PSEUDO_NMI 223 select HAVE_PERF_REGS 224 select HAVE_PERF_USER_STACK_DUMP 225 select HAVE_PREEMPT_DYNAMIC_KEY 226 select HAVE_REGS_AND_STACK_ACCESS_API 227 select HAVE_POSIX_CPU_TIMERS_TASK_WORK 228 select HAVE_FUNCTION_ARG_ACCESS_API 229 select MMU_GATHER_RCU_TABLE_FREE 230 select HAVE_RSEQ 231 select HAVE_STACKPROTECTOR 232 select HAVE_SYSCALL_TRACEPOINTS 233 select HAVE_KPROBES 234 select HAVE_KRETPROBES 235 select HAVE_GENERIC_VDSO 236 select HOTPLUG_CORE_SYNC_DEAD if HOTPLUG_CPU 237 select IRQ_DOMAIN 238 select IRQ_FORCED_THREADING 239 select KASAN_VMALLOC if KASAN 240 select LOCK_MM_AND_FIND_VMA 241 select MODULES_USE_ELF_RELA 242 select NEED_DMA_MAP_STATE 243 select NEED_SG_DMA_LENGTH 244 select OF 245 select OF_EARLY_FLATTREE 246 select PCI_DOMAINS_GENERIC if PCI 247 select PCI_ECAM if (ACPI && PCI) 248 select PCI_SYSCALL if PCI 249 select POWER_RESET 250 select POWER_SUPPLY 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 TRACE_IRQFLAGS_SUPPORT 257 select TRACE_IRQFLAGS_NMI_SUPPORT 258 select HAVE_SOFTIRQ_ON_OWN_STACK 259 help 260 ARM 64-bit (AArch64) Linux support. 261 262config CLANG_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS 263 def_bool CC_IS_CLANG 264 # https://github.com/ClangBuiltLinux/linux/issues/1507 265 depends on AS_IS_GNU || (AS_IS_LLVM && (LD_IS_LLD || LD_VERSION >= 23600)) 266 267config GCC_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS 268 def_bool CC_IS_GCC 269 depends on $(cc-option,-fpatchable-function-entry=2) 270 271config 64BIT 272 def_bool y 273 274config MMU 275 def_bool y 276 277config ARM64_PAGE_SHIFT 278 int 279 default 16 if ARM64_64K_PAGES 280 default 14 if ARM64_16K_PAGES 281 default 12 282 283config ARM64_CONT_PTE_SHIFT 284 int 285 default 5 if ARM64_64K_PAGES 286 default 7 if ARM64_16K_PAGES 287 default 4 288 289config ARM64_CONT_PMD_SHIFT 290 int 291 default 5 if ARM64_64K_PAGES 292 default 5 if ARM64_16K_PAGES 293 default 4 294 295config ARCH_MMAP_RND_BITS_MIN 296 default 14 if ARM64_64K_PAGES 297 default 16 if ARM64_16K_PAGES 298 default 18 299 300# max bits determined by the following formula: 301# VA_BITS - PAGE_SHIFT - 3 302config ARCH_MMAP_RND_BITS_MAX 303 default 19 if ARM64_VA_BITS=36 304 default 24 if ARM64_VA_BITS=39 305 default 27 if ARM64_VA_BITS=42 306 default 30 if ARM64_VA_BITS=47 307 default 29 if ARM64_VA_BITS=48 && ARM64_64K_PAGES 308 default 31 if ARM64_VA_BITS=48 && ARM64_16K_PAGES 309 default 33 if ARM64_VA_BITS=48 310 default 14 if ARM64_64K_PAGES 311 default 16 if ARM64_16K_PAGES 312 default 18 313 314config ARCH_MMAP_RND_COMPAT_BITS_MIN 315 default 7 if ARM64_64K_PAGES 316 default 9 if ARM64_16K_PAGES 317 default 11 318 319config ARCH_MMAP_RND_COMPAT_BITS_MAX 320 default 16 321 322config NO_IOPORT_MAP 323 def_bool y if !PCI 324 325config STACKTRACE_SUPPORT 326 def_bool y 327 328config ILLEGAL_POINTER_VALUE 329 hex 330 default 0xdead000000000000 331 332config LOCKDEP_SUPPORT 333 def_bool y 334 335config GENERIC_BUG 336 def_bool y 337 depends on BUG 338 339config GENERIC_BUG_RELATIVE_POINTERS 340 def_bool y 341 depends on GENERIC_BUG 342 343config GENERIC_HWEIGHT 344 def_bool y 345 346config GENERIC_CSUM 347 def_bool y 348 349config GENERIC_CALIBRATE_DELAY 350 def_bool y 351 352config SMP 353 def_bool y 354 355config KERNEL_MODE_NEON 356 def_bool y 357 358config FIX_EARLYCON_MEM 359 def_bool y 360 361config PGTABLE_LEVELS 362 int 363 default 2 if ARM64_16K_PAGES && ARM64_VA_BITS_36 364 default 2 if ARM64_64K_PAGES && ARM64_VA_BITS_42 365 default 3 if ARM64_64K_PAGES && (ARM64_VA_BITS_48 || ARM64_VA_BITS_52) 366 default 3 if ARM64_4K_PAGES && ARM64_VA_BITS_39 367 default 3 if ARM64_16K_PAGES && ARM64_VA_BITS_47 368 default 4 if !ARM64_64K_PAGES && ARM64_VA_BITS_48 369 370config ARCH_SUPPORTS_UPROBES 371 def_bool y 372 373config ARCH_PROC_KCORE_TEXT 374 def_bool y 375 376config BROKEN_GAS_INST 377 def_bool !$(as-instr,1:\n.inst 0\n.rept . - 1b\n\nnop\n.endr\n) 378 379config BUILTIN_RETURN_ADDRESS_STRIPS_PAC 380 bool 381 # Clang's __builtin_return_adddress() strips the PAC since 12.0.0 382 # https://reviews.llvm.org/D75044 383 default y if CC_IS_CLANG && (CLANG_VERSION >= 120000) 384 # GCC's __builtin_return_address() strips the PAC since 11.1.0, 385 # and this was backported to 10.2.0, 9.4.0, 8.5.0, but not earlier 386 # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94891 387 default y if CC_IS_GCC && (GCC_VERSION >= 110100) 388 default y if CC_IS_GCC && (GCC_VERSION >= 100200) && (GCC_VERSION < 110000) 389 default y if CC_IS_GCC && (GCC_VERSION >= 90400) && (GCC_VERSION < 100000) 390 default y if CC_IS_GCC && (GCC_VERSION >= 80500) && (GCC_VERSION < 90000) 391 default n 392 393config KASAN_SHADOW_OFFSET 394 hex 395 depends on KASAN_GENERIC || KASAN_SW_TAGS 396 default 0xdfff800000000000 if (ARM64_VA_BITS_48 || ARM64_VA_BITS_52) && !KASAN_SW_TAGS 397 default 0xdfffc00000000000 if ARM64_VA_BITS_47 && !KASAN_SW_TAGS 398 default 0xdffffe0000000000 if ARM64_VA_BITS_42 && !KASAN_SW_TAGS 399 default 0xdfffffc000000000 if ARM64_VA_BITS_39 && !KASAN_SW_TAGS 400 default 0xdffffff800000000 if ARM64_VA_BITS_36 && !KASAN_SW_TAGS 401 default 0xefff800000000000 if (ARM64_VA_BITS_48 || ARM64_VA_BITS_52) && KASAN_SW_TAGS 402 default 0xefffc00000000000 if ARM64_VA_BITS_47 && KASAN_SW_TAGS 403 default 0xeffffe0000000000 if ARM64_VA_BITS_42 && KASAN_SW_TAGS 404 default 0xefffffc000000000 if ARM64_VA_BITS_39 && KASAN_SW_TAGS 405 default 0xeffffff800000000 if ARM64_VA_BITS_36 && KASAN_SW_TAGS 406 default 0xffffffffffffffff 407 408config UNWIND_TABLES 409 bool 410 411source "arch/arm64/Kconfig.platforms" 412 413menu "Kernel Features" 414 415menu "ARM errata workarounds via the alternatives framework" 416 417config AMPERE_ERRATUM_AC03_CPU_38 418 bool "AmpereOne: AC03_CPU_38: Certain bits in the Virtualization Translation Control Register and Translation Control Registers do not follow RES0 semantics" 419 default y 420 help 421 This option adds an alternative code sequence to work around Ampere 422 errata AC03_CPU_38 and AC04_CPU_10 on AmpereOne. 423 424 The affected design reports FEAT_HAFDBS as not implemented in 425 ID_AA64MMFR1_EL1.HAFDBS, but (V)TCR_ELx.{HA,HD} are not RES0 426 as required by the architecture. The unadvertised HAFDBS 427 implementation suffers from an additional erratum where hardware 428 A/D updates can occur after a PTE has been marked invalid. 429 430 The workaround forces KVM to explicitly set VTCR_EL2.HA to 0, 431 which avoids enabling unadvertised hardware Access Flag management 432 at stage-2. 433 434 If unsure, say Y. 435 436config ARM64_WORKAROUND_CLEAN_CACHE 437 bool 438 439config ARM64_ERRATUM_826319 440 bool "Cortex-A53: 826319: System might deadlock if a write cannot complete until read data is accepted" 441 default y 442 select ARM64_WORKAROUND_CLEAN_CACHE 443 help 444 This option adds an alternative code sequence to work around ARM 445 erratum 826319 on Cortex-A53 parts up to r0p2 with an AMBA 4 ACE or 446 AXI master interface and an L2 cache. 447 448 If a Cortex-A53 uses an AMBA AXI4 ACE interface to other processors 449 and is unable to accept a certain write via this interface, it will 450 not progress on read data presented on the read data channel and the 451 system can deadlock. 452 453 The workaround promotes data cache clean instructions to 454 data cache clean-and-invalidate. 455 Please note that this does not necessarily enable the workaround, 456 as it depends on the alternative framework, which will only patch 457 the kernel if an affected CPU is detected. 458 459 If unsure, say Y. 460 461config ARM64_ERRATUM_827319 462 bool "Cortex-A53: 827319: Data cache clean instructions might cause overlapping transactions to the interconnect" 463 default y 464 select ARM64_WORKAROUND_CLEAN_CACHE 465 help 466 This option adds an alternative code sequence to work around ARM 467 erratum 827319 on Cortex-A53 parts up to r0p2 with an AMBA 5 CHI 468 master interface and an L2 cache. 469 470 Under certain conditions this erratum can cause a clean line eviction 471 to occur at the same time as another transaction to the same address 472 on the AMBA 5 CHI interface, which can cause data corruption if the 473 interconnect reorders the two transactions. 474 475 The workaround promotes data cache clean instructions to 476 data cache clean-and-invalidate. 477 Please note that this does not necessarily enable the workaround, 478 as it depends on the alternative framework, which will only patch 479 the kernel if an affected CPU is detected. 480 481 If unsure, say Y. 482 483config ARM64_ERRATUM_824069 484 bool "Cortex-A53: 824069: Cache line might not be marked as clean after a CleanShared snoop" 485 default y 486 select ARM64_WORKAROUND_CLEAN_CACHE 487 help 488 This option adds an alternative code sequence to work around ARM 489 erratum 824069 on Cortex-A53 parts up to r0p2 when it is connected 490 to a coherent interconnect. 491 492 If a Cortex-A53 processor is executing a store or prefetch for 493 write instruction at the same time as a processor in another 494 cluster is executing a cache maintenance operation to the same 495 address, then this erratum might cause a clean cache line to be 496 incorrectly marked as dirty. 497 498 The workaround promotes data cache clean instructions to 499 data cache clean-and-invalidate. 500 Please note that this option does not necessarily enable the 501 workaround, as it depends on the alternative framework, which will 502 only patch the kernel if an affected CPU is detected. 503 504 If unsure, say Y. 505 506config ARM64_ERRATUM_819472 507 bool "Cortex-A53: 819472: Store exclusive instructions might cause data corruption" 508 default y 509 select ARM64_WORKAROUND_CLEAN_CACHE 510 help 511 This option adds an alternative code sequence to work around ARM 512 erratum 819472 on Cortex-A53 parts up to r0p1 with an L2 cache 513 present when it is connected to a coherent interconnect. 514 515 If the processor is executing a load and store exclusive sequence at 516 the same time as a processor in another cluster is executing a cache 517 maintenance operation to the same address, then this erratum might 518 cause data corruption. 519 520 The workaround promotes data cache clean instructions to 521 data cache clean-and-invalidate. 522 Please note that this does not necessarily enable the workaround, 523 as it depends on the alternative framework, which will only patch 524 the kernel if an affected CPU is detected. 525 526 If unsure, say Y. 527 528config ARM64_ERRATUM_832075 529 bool "Cortex-A57: 832075: possible deadlock on mixing exclusive memory accesses with device loads" 530 default y 531 help 532 This option adds an alternative code sequence to work around ARM 533 erratum 832075 on Cortex-A57 parts up to r1p2. 534 535 Affected Cortex-A57 parts might deadlock when exclusive load/store 536 instructions to Write-Back memory are mixed with Device loads. 537 538 The workaround is to promote device loads to use Load-Acquire 539 semantics. 540 Please note that this does not necessarily enable the workaround, 541 as it depends on the alternative framework, which will only patch 542 the kernel if an affected CPU is detected. 543 544 If unsure, say Y. 545 546config ARM64_ERRATUM_834220 547 bool "Cortex-A57: 834220: Stage 2 translation fault might be incorrectly reported in presence of a Stage 1 fault" 548 depends on KVM 549 default y 550 help 551 This option adds an alternative code sequence to work around ARM 552 erratum 834220 on Cortex-A57 parts up to r1p2. 553 554 Affected Cortex-A57 parts might report a Stage 2 translation 555 fault as the result of a Stage 1 fault for load crossing a 556 page boundary when there is a permission or device memory 557 alignment fault at Stage 1 and a translation fault at Stage 2. 558 559 The workaround is to verify that the Stage 1 translation 560 doesn't generate a fault before handling the Stage 2 fault. 561 Please note that this does not necessarily enable the workaround, 562 as it depends on the alternative framework, which will only patch 563 the kernel if an affected CPU is detected. 564 565 If unsure, say Y. 566 567config ARM64_ERRATUM_1742098 568 bool "Cortex-A57/A72: 1742098: ELR recorded incorrectly on interrupt taken between cryptographic instructions in a sequence" 569 depends on COMPAT 570 default y 571 help 572 This option removes the AES hwcap for aarch32 user-space to 573 workaround erratum 1742098 on Cortex-A57 and Cortex-A72. 574 575 Affected parts may corrupt the AES state if an interrupt is 576 taken between a pair of AES instructions. These instructions 577 are only present if the cryptography extensions are present. 578 All software should have a fallback implementation for CPUs 579 that don't implement the cryptography extensions. 580 581 If unsure, say Y. 582 583config ARM64_ERRATUM_845719 584 bool "Cortex-A53: 845719: a load might read incorrect data" 585 depends on COMPAT 586 default y 587 help 588 This option adds an alternative code sequence to work around ARM 589 erratum 845719 on Cortex-A53 parts up to r0p4. 590 591 When running a compat (AArch32) userspace on an affected Cortex-A53 592 part, a load at EL0 from a virtual address that matches the bottom 32 593 bits of the virtual address used by a recent load at (AArch64) EL1 594 might return incorrect data. 595 596 The workaround is to write the contextidr_el1 register on exception 597 return to a 32-bit task. 598 Please note that this does not necessarily enable the workaround, 599 as it depends on the alternative framework, which will only patch 600 the kernel if an affected CPU is detected. 601 602 If unsure, say Y. 603 604config ARM64_ERRATUM_843419 605 bool "Cortex-A53: 843419: A load or store might access an incorrect address" 606 default y 607 help 608 This option links the kernel with '--fix-cortex-a53-843419' and 609 enables PLT support to replace certain ADRP instructions, which can 610 cause subsequent memory accesses to use an incorrect address on 611 Cortex-A53 parts up to r0p4. 612 613 If unsure, say Y. 614 615config ARM64_LD_HAS_FIX_ERRATUM_843419 616 def_bool $(ld-option,--fix-cortex-a53-843419) 617 618config ARM64_ERRATUM_1024718 619 bool "Cortex-A55: 1024718: Update of DBM/AP bits without break before make might result in incorrect update" 620 default y 621 help 622 This option adds a workaround for ARM Cortex-A55 Erratum 1024718. 623 624 Affected Cortex-A55 cores (all revisions) could cause incorrect 625 update of the hardware dirty bit when the DBM/AP bits are updated 626 without a break-before-make. The workaround is to disable the usage 627 of hardware DBM locally on the affected cores. CPUs not affected by 628 this erratum will continue to use the feature. 629 630 If unsure, say Y. 631 632config ARM64_ERRATUM_1418040 633 bool "Cortex-A76/Neoverse-N1: MRC read following MRRC read of specific Generic Timer in AArch32 might give incorrect result" 634 default y 635 depends on COMPAT 636 help 637 This option adds a workaround for ARM Cortex-A76/Neoverse-N1 638 errata 1188873 and 1418040. 639 640 Affected Cortex-A76/Neoverse-N1 cores (r0p0 to r3p1) could 641 cause register corruption when accessing the timer registers 642 from AArch32 userspace. 643 644 If unsure, say Y. 645 646config ARM64_WORKAROUND_SPECULATIVE_AT 647 bool 648 649config ARM64_ERRATUM_1165522 650 bool "Cortex-A76: 1165522: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation" 651 default y 652 select ARM64_WORKAROUND_SPECULATIVE_AT 653 help 654 This option adds a workaround for ARM Cortex-A76 erratum 1165522. 655 656 Affected Cortex-A76 cores (r0p0, r1p0, r2p0) could end-up with 657 corrupted TLBs by speculating an AT instruction during a guest 658 context switch. 659 660 If unsure, say Y. 661 662config ARM64_ERRATUM_1319367 663 bool "Cortex-A57/A72: 1319537: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation" 664 default y 665 select ARM64_WORKAROUND_SPECULATIVE_AT 666 help 667 This option adds work arounds for ARM Cortex-A57 erratum 1319537 668 and A72 erratum 1319367 669 670 Cortex-A57 and A72 cores could end-up with corrupted TLBs by 671 speculating an AT instruction during a guest context switch. 672 673 If unsure, say Y. 674 675config ARM64_ERRATUM_1530923 676 bool "Cortex-A55: 1530923: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation" 677 default y 678 select ARM64_WORKAROUND_SPECULATIVE_AT 679 help 680 This option adds a workaround for ARM Cortex-A55 erratum 1530923. 681 682 Affected Cortex-A55 cores (r0p0, r0p1, r1p0, r2p0) could end-up with 683 corrupted TLBs by speculating an AT instruction during a guest 684 context switch. 685 686 If unsure, say Y. 687 688config ARM64_WORKAROUND_REPEAT_TLBI 689 bool 690 691config ARM64_ERRATUM_2441007 692 bool "Cortex-A55: Completion of affected memory accesses might not be guaranteed by completion of a TLBI" 693 default y 694 select ARM64_WORKAROUND_REPEAT_TLBI 695 help 696 This option adds a workaround for ARM Cortex-A55 erratum #2441007. 697 698 Under very rare circumstances, affected Cortex-A55 CPUs 699 may not handle a race between a break-before-make sequence on one 700 CPU, and another CPU accessing the same page. This could allow a 701 store to a page that has been unmapped. 702 703 Work around this by adding the affected CPUs to the list that needs 704 TLB sequences to be done twice. 705 706 If unsure, say Y. 707 708config ARM64_ERRATUM_1286807 709 bool "Cortex-A76: Modification of the translation table for a virtual address might lead to read-after-read ordering violation" 710 default y 711 select ARM64_WORKAROUND_REPEAT_TLBI 712 help 713 This option adds a workaround for ARM Cortex-A76 erratum 1286807. 714 715 On the affected Cortex-A76 cores (r0p0 to r3p0), if a virtual 716 address for a cacheable mapping of a location is being 717 accessed by a core while another core is remapping the virtual 718 address to a new physical page using the recommended 719 break-before-make sequence, then under very rare circumstances 720 TLBI+DSB completes before a read using the translation being 721 invalidated has been observed by other observers. The 722 workaround repeats the TLBI+DSB operation. 723 724config ARM64_ERRATUM_1463225 725 bool "Cortex-A76: Software Step might prevent interrupt recognition" 726 default y 727 help 728 This option adds a workaround for Arm Cortex-A76 erratum 1463225. 729 730 On the affected Cortex-A76 cores (r0p0 to r3p1), software stepping 731 of a system call instruction (SVC) can prevent recognition of 732 subsequent interrupts when software stepping is disabled in the 733 exception handler of the system call and either kernel debugging 734 is enabled or VHE is in use. 735 736 Work around the erratum by triggering a dummy step exception 737 when handling a system call from a task that is being stepped 738 in a VHE configuration of the kernel. 739 740 If unsure, say Y. 741 742config ARM64_ERRATUM_1542419 743 bool "Neoverse-N1: workaround mis-ordering of instruction fetches" 744 default y 745 help 746 This option adds a workaround for ARM Neoverse-N1 erratum 747 1542419. 748 749 Affected Neoverse-N1 cores could execute a stale instruction when 750 modified by another CPU. The workaround depends on a firmware 751 counterpart. 752 753 Workaround the issue by hiding the DIC feature from EL0. This 754 forces user-space to perform cache maintenance. 755 756 If unsure, say Y. 757 758config ARM64_ERRATUM_1508412 759 bool "Cortex-A77: 1508412: workaround deadlock on sequence of NC/Device load and store exclusive or PAR read" 760 default y 761 help 762 This option adds a workaround for Arm Cortex-A77 erratum 1508412. 763 764 Affected Cortex-A77 cores (r0p0, r1p0) could deadlock on a sequence 765 of a store-exclusive or read of PAR_EL1 and a load with device or 766 non-cacheable memory attributes. The workaround depends on a firmware 767 counterpart. 768 769 KVM guests must also have the workaround implemented or they can 770 deadlock the system. 771 772 Work around the issue by inserting DMB SY barriers around PAR_EL1 773 register reads and warning KVM users. The DMB barrier is sufficient 774 to prevent a speculative PAR_EL1 read. 775 776 If unsure, say Y. 777 778config ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE 779 bool 780 781config ARM64_ERRATUM_2051678 782 bool "Cortex-A510: 2051678: disable Hardware Update of the page table dirty bit" 783 default y 784 help 785 This options adds the workaround for ARM Cortex-A510 erratum ARM64_ERRATUM_2051678. 786 Affected Cortex-A510 might not respect the ordering rules for 787 hardware update of the page table's dirty bit. The workaround 788 is to not enable the feature on affected CPUs. 789 790 If unsure, say Y. 791 792config ARM64_ERRATUM_2077057 793 bool "Cortex-A510: 2077057: workaround software-step corrupting SPSR_EL2" 794 default y 795 help 796 This option adds the workaround for ARM Cortex-A510 erratum 2077057. 797 Affected Cortex-A510 may corrupt SPSR_EL2 when the a step exception is 798 expected, but a Pointer Authentication trap is taken instead. The 799 erratum causes SPSR_EL1 to be copied to SPSR_EL2, which could allow 800 EL1 to cause a return to EL2 with a guest controlled ELR_EL2. 801 802 This can only happen when EL2 is stepping EL1. 803 804 When these conditions occur, the SPSR_EL2 value is unchanged from the 805 previous guest entry, and can be restored from the in-memory copy. 806 807 If unsure, say Y. 808 809config ARM64_ERRATUM_2658417 810 bool "Cortex-A510: 2658417: remove BF16 support due to incorrect result" 811 default y 812 help 813 This option adds the workaround for ARM Cortex-A510 erratum 2658417. 814 Affected Cortex-A510 (r0p0 to r1p1) may produce the wrong result for 815 BFMMLA or VMMLA instructions in rare circumstances when a pair of 816 A510 CPUs are using shared neon hardware. As the sharing is not 817 discoverable by the kernel, hide the BF16 HWCAP to indicate that 818 user-space should not be using these instructions. 819 820 If unsure, say Y. 821 822config ARM64_ERRATUM_2119858 823 bool "Cortex-A710/X2: 2119858: workaround TRBE overwriting trace data in FILL mode" 824 default y 825 depends on CORESIGHT_TRBE 826 select ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE 827 help 828 This option adds the workaround for ARM Cortex-A710/X2 erratum 2119858. 829 830 Affected Cortex-A710/X2 cores could overwrite up to 3 cache lines of trace 831 data at the base of the buffer (pointed to by TRBASER_EL1) in FILL mode in 832 the event of a WRAP event. 833 834 Work around the issue by always making sure we move the TRBPTR_EL1 by 835 256 bytes before enabling the buffer and filling the first 256 bytes of 836 the buffer with ETM ignore packets upon disabling. 837 838 If unsure, say Y. 839 840config ARM64_ERRATUM_2139208 841 bool "Neoverse-N2: 2139208: workaround TRBE overwriting trace data in FILL mode" 842 default y 843 depends on CORESIGHT_TRBE 844 select ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE 845 help 846 This option adds the workaround for ARM Neoverse-N2 erratum 2139208. 847 848 Affected Neoverse-N2 cores could overwrite up to 3 cache lines of trace 849 data at the base of the buffer (pointed to by TRBASER_EL1) in FILL mode in 850 the event of a WRAP event. 851 852 Work around the issue by always making sure we move the TRBPTR_EL1 by 853 256 bytes before enabling the buffer and filling the first 256 bytes of 854 the buffer with ETM ignore packets upon disabling. 855 856 If unsure, say Y. 857 858config ARM64_WORKAROUND_TSB_FLUSH_FAILURE 859 bool 860 861config ARM64_ERRATUM_2054223 862 bool "Cortex-A710: 2054223: workaround TSB instruction failing to flush trace" 863 default y 864 select ARM64_WORKAROUND_TSB_FLUSH_FAILURE 865 help 866 Enable workaround for ARM Cortex-A710 erratum 2054223 867 868 Affected cores may fail to flush the trace data on a TSB instruction, when 869 the PE is in trace prohibited state. This will cause losing a few bytes 870 of the trace cached. 871 872 Workaround is to issue two TSB consecutively on affected cores. 873 874 If unsure, say Y. 875 876config ARM64_ERRATUM_2067961 877 bool "Neoverse-N2: 2067961: workaround TSB instruction failing to flush trace" 878 default y 879 select ARM64_WORKAROUND_TSB_FLUSH_FAILURE 880 help 881 Enable workaround for ARM Neoverse-N2 erratum 2067961 882 883 Affected cores may fail to flush the trace data on a TSB instruction, when 884 the PE is in trace prohibited state. This will cause losing a few bytes 885 of the trace cached. 886 887 Workaround is to issue two TSB consecutively on affected cores. 888 889 If unsure, say Y. 890 891config ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE 892 bool 893 894config ARM64_ERRATUM_2253138 895 bool "Neoverse-N2: 2253138: workaround TRBE writing to address out-of-range" 896 depends on CORESIGHT_TRBE 897 default y 898 select ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE 899 help 900 This option adds the workaround for ARM Neoverse-N2 erratum 2253138. 901 902 Affected Neoverse-N2 cores might write to an out-of-range address, not reserved 903 for TRBE. Under some conditions, the TRBE might generate a write to the next 904 virtually addressed page following the last page of the TRBE address space 905 (i.e., the TRBLIMITR_EL1.LIMIT), instead of wrapping around to the base. 906 907 Work around this in the driver by always making sure that there is a 908 page beyond the TRBLIMITR_EL1.LIMIT, within the space allowed for the TRBE. 909 910 If unsure, say Y. 911 912config ARM64_ERRATUM_2224489 913 bool "Cortex-A710/X2: 2224489: workaround TRBE writing to address out-of-range" 914 depends on CORESIGHT_TRBE 915 default y 916 select ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE 917 help 918 This option adds the workaround for ARM Cortex-A710/X2 erratum 2224489. 919 920 Affected Cortex-A710/X2 cores might write to an out-of-range address, not reserved 921 for TRBE. Under some conditions, the TRBE might generate a write to the next 922 virtually addressed page following the last page of the TRBE address space 923 (i.e., the TRBLIMITR_EL1.LIMIT), instead of wrapping around to the base. 924 925 Work around this in the driver by always making sure that there is a 926 page beyond the TRBLIMITR_EL1.LIMIT, within the space allowed for the TRBE. 927 928 If unsure, say Y. 929 930config ARM64_ERRATUM_2441009 931 bool "Cortex-A510: Completion of affected memory accesses might not be guaranteed by completion of a TLBI" 932 default y 933 select ARM64_WORKAROUND_REPEAT_TLBI 934 help 935 This option adds a workaround for ARM Cortex-A510 erratum #2441009. 936 937 Under very rare circumstances, affected Cortex-A510 CPUs 938 may not handle a race between a break-before-make sequence on one 939 CPU, and another CPU accessing the same page. This could allow a 940 store to a page that has been unmapped. 941 942 Work around this by adding the affected CPUs to the list that needs 943 TLB sequences to be done twice. 944 945 If unsure, say Y. 946 947config ARM64_ERRATUM_2064142 948 bool "Cortex-A510: 2064142: workaround TRBE register writes while disabled" 949 depends on CORESIGHT_TRBE 950 default y 951 help 952 This option adds the workaround for ARM Cortex-A510 erratum 2064142. 953 954 Affected Cortex-A510 core might fail to write into system registers after the 955 TRBE has been disabled. Under some conditions after the TRBE has been disabled 956 writes into TRBE registers TRBLIMITR_EL1, TRBPTR_EL1, TRBBASER_EL1, TRBSR_EL1, 957 and TRBTRG_EL1 will be ignored and will not be effected. 958 959 Work around this in the driver by executing TSB CSYNC and DSB after collection 960 is stopped and before performing a system register write to one of the affected 961 registers. 962 963 If unsure, say Y. 964 965config ARM64_ERRATUM_2038923 966 bool "Cortex-A510: 2038923: workaround TRBE corruption with enable" 967 depends on CORESIGHT_TRBE 968 default y 969 help 970 This option adds the workaround for ARM Cortex-A510 erratum 2038923. 971 972 Affected Cortex-A510 core might cause an inconsistent view on whether trace is 973 prohibited within the CPU. As a result, the trace buffer or trace buffer state 974 might be corrupted. This happens after TRBE buffer has been enabled by setting 975 TRBLIMITR_EL1.E, followed by just a single context synchronization event before 976 execution changes from a context, in which trace is prohibited to one where it 977 isn't, or vice versa. In these mentioned conditions, the view of whether trace 978 is prohibited is inconsistent between parts of the CPU, and the trace buffer or 979 the trace buffer state might be corrupted. 980 981 Work around this in the driver by preventing an inconsistent view of whether the 982 trace is prohibited or not based on TRBLIMITR_EL1.E by immediately following a 983 change to TRBLIMITR_EL1.E with at least one ISB instruction before an ERET, or 984 two ISB instructions if no ERET is to take place. 985 986 If unsure, say Y. 987 988config ARM64_ERRATUM_1902691 989 bool "Cortex-A510: 1902691: workaround TRBE trace corruption" 990 depends on CORESIGHT_TRBE 991 default y 992 help 993 This option adds the workaround for ARM Cortex-A510 erratum 1902691. 994 995 Affected Cortex-A510 core might cause trace data corruption, when being written 996 into the memory. Effectively TRBE is broken and hence cannot be used to capture 997 trace data. 998 999 Work around this problem in the driver by just preventing TRBE initialization on 1000 affected cpus. The firmware must have disabled the access to TRBE for the kernel 1001 on such implementations. This will cover the kernel for any firmware that doesn't 1002 do this already. 1003 1004 If unsure, say Y. 1005 1006config ARM64_ERRATUM_2457168 1007 bool "Cortex-A510: 2457168: workaround for AMEVCNTR01 incrementing incorrectly" 1008 depends on ARM64_AMU_EXTN 1009 default y 1010 help 1011 This option adds the workaround for ARM Cortex-A510 erratum 2457168. 1012 1013 The AMU counter AMEVCNTR01 (constant counter) should increment at the same rate 1014 as the system counter. On affected Cortex-A510 cores AMEVCNTR01 increments 1015 incorrectly giving a significantly higher output value. 1016 1017 Work around this problem by returning 0 when reading the affected counter in 1018 key locations that results in disabling all users of this counter. This effect 1019 is the same to firmware disabling affected counters. 1020 1021 If unsure, say Y. 1022 1023config ARM64_ERRATUM_2645198 1024 bool "Cortex-A715: 2645198: Workaround possible [ESR|FAR]_ELx corruption" 1025 default y 1026 help 1027 This option adds the workaround for ARM Cortex-A715 erratum 2645198. 1028 1029 If a Cortex-A715 cpu sees a page mapping permissions change from executable 1030 to non-executable, it may corrupt the ESR_ELx and FAR_ELx registers on the 1031 next instruction abort caused by permission fault. 1032 1033 Only user-space does executable to non-executable permission transition via 1034 mprotect() system call. Workaround the problem by doing a break-before-make 1035 TLB invalidation, for all changes to executable user space mappings. 1036 1037 If unsure, say Y. 1038 1039config ARM64_WORKAROUND_SPECULATIVE_UNPRIV_LOAD 1040 bool 1041 1042config ARM64_ERRATUM_2966298 1043 bool "Cortex-A520: 2966298: workaround for speculatively executed unprivileged load" 1044 select ARM64_WORKAROUND_SPECULATIVE_UNPRIV_LOAD 1045 default y 1046 help 1047 This option adds the workaround for ARM Cortex-A520 erratum 2966298. 1048 1049 On an affected Cortex-A520 core, a speculatively executed unprivileged 1050 load might leak data from a privileged level via a cache side channel. 1051 1052 Work around this problem by executing a TLBI before returning to EL0. 1053 1054 If unsure, say Y. 1055 1056config ARM64_ERRATUM_3117295 1057 bool "Cortex-A510: 3117295: workaround for speculatively executed unprivileged load" 1058 select ARM64_WORKAROUND_SPECULATIVE_UNPRIV_LOAD 1059 default y 1060 help 1061 This option adds the workaround for ARM Cortex-A510 erratum 3117295. 1062 1063 On an affected Cortex-A510 core, a speculatively executed unprivileged 1064 load might leak data from a privileged level via a cache side channel. 1065 1066 Work around this problem by executing a TLBI before returning to EL0. 1067 1068 If unsure, say Y. 1069 1070config ARM64_ERRATUM_3194386 1071 bool "Cortex-*/Neoverse-*: workaround for MSR SSBS not self-synchronizing" 1072 default y 1073 help 1074 This option adds the workaround for the following errata: 1075 1076 * ARM Cortex-A76 erratum 3324349 1077 * ARM Cortex-A77 erratum 3324348 1078 * ARM Cortex-A78 erratum 3324344 1079 * ARM Cortex-A78C erratum 3324346 1080 * ARM Cortex-A78C erratum 3324347 1081 * ARM Cortex-A710 erratam 3324338 1082 * ARM Cortex-A715 errartum 3456084 1083 * ARM Cortex-A720 erratum 3456091 1084 * ARM Cortex-A725 erratum 3456106 1085 * ARM Cortex-X1 erratum 3324344 1086 * ARM Cortex-X1C erratum 3324346 1087 * ARM Cortex-X2 erratum 3324338 1088 * ARM Cortex-X3 erratum 3324335 1089 * ARM Cortex-X4 erratum 3194386 1090 * ARM Cortex-X925 erratum 3324334 1091 * ARM Neoverse-N1 erratum 3324349 1092 * ARM Neoverse N2 erratum 3324339 1093 * ARM Neoverse-N3 erratum 3456111 1094 * ARM Neoverse-V1 erratum 3324341 1095 * ARM Neoverse V2 erratum 3324336 1096 * ARM Neoverse-V3 erratum 3312417 1097 1098 On affected cores "MSR SSBS, #0" instructions may not affect 1099 subsequent speculative instructions, which may permit unexepected 1100 speculative store bypassing. 1101 1102 Work around this problem by placing a Speculation Barrier (SB) or 1103 Instruction Synchronization Barrier (ISB) after kernel changes to 1104 SSBS. The presence of the SSBS special-purpose register is hidden 1105 from hwcaps and EL0 reads of ID_AA64PFR1_EL1, such that userspace 1106 will use the PR_SPEC_STORE_BYPASS prctl to change SSBS. 1107 1108 If unsure, say Y. 1109 1110config CAVIUM_ERRATUM_22375 1111 bool "Cavium erratum 22375, 24313" 1112 default y 1113 help 1114 Enable workaround for errata 22375 and 24313. 1115 1116 This implements two gicv3-its errata workarounds for ThunderX. Both 1117 with a small impact affecting only ITS table allocation. 1118 1119 erratum 22375: only alloc 8MB table size 1120 erratum 24313: ignore memory access type 1121 1122 The fixes are in ITS initialization and basically ignore memory access 1123 type and table size provided by the TYPER and BASER registers. 1124 1125 If unsure, say Y. 1126 1127config CAVIUM_ERRATUM_23144 1128 bool "Cavium erratum 23144: ITS SYNC hang on dual socket system" 1129 depends on NUMA 1130 default y 1131 help 1132 ITS SYNC command hang for cross node io and collections/cpu mapping. 1133 1134 If unsure, say Y. 1135 1136config CAVIUM_ERRATUM_23154 1137 bool "Cavium errata 23154 and 38545: GICv3 lacks HW synchronisation" 1138 default y 1139 help 1140 The ThunderX GICv3 implementation requires a modified version for 1141 reading the IAR status to ensure data synchronization 1142 (access to icc_iar1_el1 is not sync'ed before and after). 1143 1144 It also suffers from erratum 38545 (also present on Marvell's 1145 OcteonTX and OcteonTX2), resulting in deactivated interrupts being 1146 spuriously presented to the CPU interface. 1147 1148 If unsure, say Y. 1149 1150config CAVIUM_ERRATUM_27456 1151 bool "Cavium erratum 27456: Broadcast TLBI instructions may cause icache corruption" 1152 default y 1153 help 1154 On ThunderX T88 pass 1.x through 2.1 parts, broadcast TLBI 1155 instructions may cause the icache to become corrupted if it 1156 contains data for a non-current ASID. The fix is to 1157 invalidate the icache when changing the mm context. 1158 1159 If unsure, say Y. 1160 1161config CAVIUM_ERRATUM_30115 1162 bool "Cavium erratum 30115: Guest may disable interrupts in host" 1163 default y 1164 help 1165 On ThunderX T88 pass 1.x through 2.2, T81 pass 1.0 through 1166 1.2, and T83 Pass 1.0, KVM guest execution may disable 1167 interrupts in host. Trapping both GICv3 group-0 and group-1 1168 accesses sidesteps the issue. 1169 1170 If unsure, say Y. 1171 1172config CAVIUM_TX2_ERRATUM_219 1173 bool "Cavium ThunderX2 erratum 219: PRFM between TTBR change and ISB fails" 1174 default y 1175 help 1176 On Cavium ThunderX2, a load, store or prefetch instruction between a 1177 TTBR update and the corresponding context synchronizing operation can 1178 cause a spurious Data Abort to be delivered to any hardware thread in 1179 the CPU core. 1180 1181 Work around the issue by avoiding the problematic code sequence and 1182 trapping KVM guest TTBRx_EL1 writes to EL2 when SMT is enabled. The 1183 trap handler performs the corresponding register access, skips the 1184 instruction and ensures context synchronization by virtue of the 1185 exception return. 1186 1187 If unsure, say Y. 1188 1189config FUJITSU_ERRATUM_010001 1190 bool "Fujitsu-A64FX erratum E#010001: Undefined fault may occur wrongly" 1191 default y 1192 help 1193 This option adds a workaround for Fujitsu-A64FX erratum E#010001. 1194 On some variants of the Fujitsu-A64FX cores ver(1.0, 1.1), memory 1195 accesses may cause undefined fault (Data abort, DFSC=0b111111). 1196 This fault occurs under a specific hardware condition when a 1197 load/store instruction performs an address translation using: 1198 case-1 TTBR0_EL1 with TCR_EL1.NFD0 == 1. 1199 case-2 TTBR0_EL2 with TCR_EL2.NFD0 == 1. 1200 case-3 TTBR1_EL1 with TCR_EL1.NFD1 == 1. 1201 case-4 TTBR1_EL2 with TCR_EL2.NFD1 == 1. 1202 1203 The workaround is to ensure these bits are clear in TCR_ELx. 1204 The workaround only affects the Fujitsu-A64FX. 1205 1206 If unsure, say Y. 1207 1208config HISILICON_ERRATUM_161600802 1209 bool "Hip07 161600802: Erroneous redistributor VLPI base" 1210 default y 1211 help 1212 The HiSilicon Hip07 SoC uses the wrong redistributor base 1213 when issued ITS commands such as VMOVP and VMAPP, and requires 1214 a 128kB offset to be applied to the target address in this commands. 1215 1216 If unsure, say Y. 1217 1218config QCOM_FALKOR_ERRATUM_1003 1219 bool "Falkor E1003: Incorrect translation due to ASID change" 1220 default y 1221 help 1222 On Falkor v1, an incorrect ASID may be cached in the TLB when ASID 1223 and BADDR are changed together in TTBRx_EL1. Since we keep the ASID 1224 in TTBR1_EL1, this situation only occurs in the entry trampoline and 1225 then only for entries in the walk cache, since the leaf translation 1226 is unchanged. Work around the erratum by invalidating the walk cache 1227 entries for the trampoline before entering the kernel proper. 1228 1229config QCOM_FALKOR_ERRATUM_1009 1230 bool "Falkor E1009: Prematurely complete a DSB after a TLBI" 1231 default y 1232 select ARM64_WORKAROUND_REPEAT_TLBI 1233 help 1234 On Falkor v1, the CPU may prematurely complete a DSB following a 1235 TLBI xxIS invalidate maintenance operation. Repeat the TLBI operation 1236 one more time to fix the issue. 1237 1238 If unsure, say Y. 1239 1240config QCOM_QDF2400_ERRATUM_0065 1241 bool "QDF2400 E0065: Incorrect GITS_TYPER.ITT_Entry_size" 1242 default y 1243 help 1244 On Qualcomm Datacenter Technologies QDF2400 SoC, ITS hardware reports 1245 ITE size incorrectly. The GITS_TYPER.ITT_Entry_size field should have 1246 been indicated as 16Bytes (0xf), not 8Bytes (0x7). 1247 1248 If unsure, say Y. 1249 1250config QCOM_FALKOR_ERRATUM_E1041 1251 bool "Falkor E1041: Speculative instruction fetches might cause errant memory access" 1252 default y 1253 help 1254 Falkor CPU may speculatively fetch instructions from an improper 1255 memory location when MMU translation is changed from SCTLR_ELn[M]=1 1256 to SCTLR_ELn[M]=0. Prefix an ISB instruction to fix the problem. 1257 1258 If unsure, say Y. 1259 1260config NVIDIA_CARMEL_CNP_ERRATUM 1261 bool "NVIDIA Carmel CNP: CNP on Carmel semantically different than ARM cores" 1262 default y 1263 help 1264 If CNP is enabled on Carmel cores, non-sharable TLBIs on a core will not 1265 invalidate shared TLB entries installed by a different core, as it would 1266 on standard ARM cores. 1267 1268 If unsure, say Y. 1269 1270config ROCKCHIP_ERRATUM_3588001 1271 bool "Rockchip 3588001: GIC600 can not support shareability attributes" 1272 default y 1273 help 1274 The Rockchip RK3588 GIC600 SoC integration does not support ACE/ACE-lite. 1275 This means, that its sharability feature may not be used, even though it 1276 is supported by the IP itself. 1277 1278 If unsure, say Y. 1279 1280config SOCIONEXT_SYNQUACER_PREITS 1281 bool "Socionext Synquacer: Workaround for GICv3 pre-ITS" 1282 default y 1283 help 1284 Socionext Synquacer SoCs implement a separate h/w block to generate 1285 MSI doorbell writes with non-zero values for the device ID. 1286 1287 If unsure, say Y. 1288 1289endmenu # "ARM errata workarounds via the alternatives framework" 1290 1291choice 1292 prompt "Page size" 1293 default ARM64_4K_PAGES 1294 help 1295 Page size (translation granule) configuration. 1296 1297config ARM64_4K_PAGES 1298 bool "4KB" 1299 help 1300 This feature enables 4KB pages support. 1301 1302config ARM64_16K_PAGES 1303 bool "16KB" 1304 help 1305 The system will use 16KB pages support. AArch32 emulation 1306 requires applications compiled with 16K (or a multiple of 16K) 1307 aligned segments. 1308 1309config ARM64_64K_PAGES 1310 bool "64KB" 1311 help 1312 This feature enables 64KB pages support (4KB by default) 1313 allowing only two levels of page tables and faster TLB 1314 look-up. AArch32 emulation requires applications compiled 1315 with 64K aligned segments. 1316 1317endchoice 1318 1319choice 1320 prompt "Virtual address space size" 1321 default ARM64_VA_BITS_39 if ARM64_4K_PAGES 1322 default ARM64_VA_BITS_47 if ARM64_16K_PAGES 1323 default ARM64_VA_BITS_42 if ARM64_64K_PAGES 1324 help 1325 Allows choosing one of multiple possible virtual address 1326 space sizes. The level of translation table is determined by 1327 a combination of page size and virtual address space size. 1328 1329config ARM64_VA_BITS_36 1330 bool "36-bit" if EXPERT 1331 depends on ARM64_16K_PAGES 1332 1333config ARM64_VA_BITS_39 1334 bool "39-bit" 1335 depends on ARM64_4K_PAGES 1336 1337config ARM64_VA_BITS_42 1338 bool "42-bit" 1339 depends on ARM64_64K_PAGES 1340 1341config ARM64_VA_BITS_47 1342 bool "47-bit" 1343 depends on ARM64_16K_PAGES 1344 1345config ARM64_VA_BITS_48 1346 bool "48-bit" 1347 1348config ARM64_VA_BITS_52 1349 bool "52-bit" 1350 depends on ARM64_64K_PAGES && (ARM64_PAN || !ARM64_SW_TTBR0_PAN) 1351 help 1352 Enable 52-bit virtual addressing for userspace when explicitly 1353 requested via a hint to mmap(). The kernel will also use 52-bit 1354 virtual addresses for its own mappings (provided HW support for 1355 this feature is available, otherwise it reverts to 48-bit). 1356 1357 NOTE: Enabling 52-bit virtual addressing in conjunction with 1358 ARMv8.3 Pointer Authentication will result in the PAC being 1359 reduced from 7 bits to 3 bits, which may have a significant 1360 impact on its susceptibility to brute-force attacks. 1361 1362 If unsure, select 48-bit virtual addressing instead. 1363 1364endchoice 1365 1366config ARM64_FORCE_52BIT 1367 bool "Force 52-bit virtual addresses for userspace" 1368 depends on ARM64_VA_BITS_52 && EXPERT 1369 help 1370 For systems with 52-bit userspace VAs enabled, the kernel will attempt 1371 to maintain compatibility with older software by providing 48-bit VAs 1372 unless a hint is supplied to mmap. 1373 1374 This configuration option disables the 48-bit compatibility logic, and 1375 forces all userspace addresses to be 52-bit on HW that supports it. One 1376 should only enable this configuration option for stress testing userspace 1377 memory management code. If unsure say N here. 1378 1379config ARM64_VA_BITS 1380 int 1381 default 36 if ARM64_VA_BITS_36 1382 default 39 if ARM64_VA_BITS_39 1383 default 42 if ARM64_VA_BITS_42 1384 default 47 if ARM64_VA_BITS_47 1385 default 48 if ARM64_VA_BITS_48 1386 default 52 if ARM64_VA_BITS_52 1387 1388choice 1389 prompt "Physical address space size" 1390 default ARM64_PA_BITS_48 1391 help 1392 Choose the maximum physical address range that the kernel will 1393 support. 1394 1395config ARM64_PA_BITS_48 1396 bool "48-bit" 1397 1398config ARM64_PA_BITS_52 1399 bool "52-bit (ARMv8.2)" 1400 depends on ARM64_64K_PAGES 1401 depends on ARM64_PAN || !ARM64_SW_TTBR0_PAN 1402 help 1403 Enable support for a 52-bit physical address space, introduced as 1404 part of the ARMv8.2-LPA extension. 1405 1406 With this enabled, the kernel will also continue to work on CPUs that 1407 do not support ARMv8.2-LPA, but with some added memory overhead (and 1408 minor performance overhead). 1409 1410endchoice 1411 1412config ARM64_PA_BITS 1413 int 1414 default 48 if ARM64_PA_BITS_48 1415 default 52 if ARM64_PA_BITS_52 1416 1417choice 1418 prompt "Endianness" 1419 default CPU_LITTLE_ENDIAN 1420 help 1421 Select the endianness of data accesses performed by the CPU. Userspace 1422 applications will need to be compiled and linked for the endianness 1423 that is selected here. 1424 1425config CPU_BIG_ENDIAN 1426 bool "Build big-endian kernel" 1427 depends on !LD_IS_LLD || LLD_VERSION >= 130000 1428 # https://github.com/llvm/llvm-project/commit/1379b150991f70a5782e9a143c2ba5308da1161c 1429 depends on AS_IS_GNU || AS_VERSION >= 150000 1430 help 1431 Say Y if you plan on running a kernel with a big-endian userspace. 1432 1433config CPU_LITTLE_ENDIAN 1434 bool "Build little-endian kernel" 1435 help 1436 Say Y if you plan on running a kernel with a little-endian userspace. 1437 This is usually the case for distributions targeting arm64. 1438 1439endchoice 1440 1441config SCHED_MC 1442 bool "Multi-core scheduler support" 1443 help 1444 Multi-core scheduler support improves the CPU scheduler's decision 1445 making when dealing with multi-core CPU chips at a cost of slightly 1446 increased overhead in some places. If unsure say N here. 1447 1448config SCHED_CLUSTER 1449 bool "Cluster scheduler support" 1450 help 1451 Cluster scheduler support improves the CPU scheduler's decision 1452 making when dealing with machines that have clusters of CPUs. 1453 Cluster usually means a couple of CPUs which are placed closely 1454 by sharing mid-level caches, last-level cache tags or internal 1455 busses. 1456 1457config SCHED_SMT 1458 bool "SMT scheduler support" 1459 help 1460 Improves the CPU scheduler's decision making when dealing with 1461 MultiThreading at a cost of slightly increased overhead in some 1462 places. If unsure say N here. 1463 1464config NR_CPUS 1465 int "Maximum number of CPUs (2-4096)" 1466 range 2 4096 1467 default "256" 1468 1469config HOTPLUG_CPU 1470 bool "Support for hot-pluggable CPUs" 1471 select GENERIC_IRQ_MIGRATION 1472 help 1473 Say Y here to experiment with turning CPUs off and on. CPUs 1474 can be controlled through /sys/devices/system/cpu. 1475 1476# Common NUMA Features 1477config NUMA 1478 bool "NUMA Memory Allocation and Scheduler Support" 1479 select GENERIC_ARCH_NUMA 1480 select ACPI_NUMA if ACPI 1481 select OF_NUMA 1482 select HAVE_SETUP_PER_CPU_AREA 1483 select NEED_PER_CPU_EMBED_FIRST_CHUNK 1484 select NEED_PER_CPU_PAGE_FIRST_CHUNK 1485 select USE_PERCPU_NUMA_NODE_ID 1486 help 1487 Enable NUMA (Non-Uniform Memory Access) support. 1488 1489 The kernel will try to allocate memory used by a CPU on the 1490 local memory of the CPU and add some more 1491 NUMA awareness to the kernel. 1492 1493config NODES_SHIFT 1494 int "Maximum NUMA Nodes (as a power of 2)" 1495 range 1 10 1496 default "4" 1497 depends on NUMA 1498 help 1499 Specify the maximum number of NUMA Nodes available on the target 1500 system. Increases memory reserved to accommodate various tables. 1501 1502source "kernel/Kconfig.hz" 1503 1504config ARCH_SPARSEMEM_ENABLE 1505 def_bool y 1506 select SPARSEMEM_VMEMMAP_ENABLE 1507 select SPARSEMEM_VMEMMAP 1508 1509config HW_PERF_EVENTS 1510 def_bool y 1511 depends on ARM_PMU 1512 1513# Supported by clang >= 7.0 or GCC >= 12.0.0 1514config CC_HAVE_SHADOW_CALL_STACK 1515 def_bool $(cc-option, -fsanitize=shadow-call-stack -ffixed-x18) 1516 1517config PARAVIRT 1518 bool "Enable paravirtualization code" 1519 help 1520 This changes the kernel so it can modify itself when it is run 1521 under a hypervisor, potentially improving performance significantly 1522 over full virtualization. 1523 1524config PARAVIRT_TIME_ACCOUNTING 1525 bool "Paravirtual steal time accounting" 1526 select PARAVIRT 1527 help 1528 Select this option to enable fine granularity task steal time 1529 accounting. Time spent executing other tasks in parallel with 1530 the current vCPU is discounted from the vCPU power. To account for 1531 that, there can be a small performance impact. 1532 1533 If in doubt, say N here. 1534 1535config ARCH_SUPPORTS_KEXEC 1536 def_bool PM_SLEEP_SMP 1537 1538config ARCH_SUPPORTS_KEXEC_FILE 1539 def_bool y 1540 1541config ARCH_SELECTS_KEXEC_FILE 1542 def_bool y 1543 depends on KEXEC_FILE 1544 select HAVE_IMA_KEXEC if IMA 1545 1546config ARCH_SUPPORTS_KEXEC_SIG 1547 def_bool y 1548 1549config ARCH_SUPPORTS_KEXEC_IMAGE_VERIFY_SIG 1550 def_bool y 1551 1552config ARCH_DEFAULT_KEXEC_IMAGE_VERIFY_SIG 1553 def_bool y 1554 1555config ARCH_SUPPORTS_CRASH_DUMP 1556 def_bool y 1557 1558config TRANS_TABLE 1559 def_bool y 1560 depends on HIBERNATION || KEXEC_CORE 1561 1562config XEN_DOM0 1563 def_bool y 1564 depends on XEN 1565 1566config XEN 1567 bool "Xen guest support on ARM64" 1568 depends on ARM64 && OF 1569 select SWIOTLB_XEN 1570 select PARAVIRT 1571 help 1572 Say Y if you want to run Linux in a Virtual Machine on Xen on ARM64. 1573 1574# include/linux/mmzone.h requires the following to be true: 1575# 1576# MAX_ORDER + PAGE_SHIFT <= SECTION_SIZE_BITS 1577# 1578# so the maximum value of MAX_ORDER is SECTION_SIZE_BITS - PAGE_SHIFT: 1579# 1580# | SECTION_SIZE_BITS | PAGE_SHIFT | max MAX_ORDER | default MAX_ORDER | 1581# ----+-------------------+--------------+-----------------+--------------------+ 1582# 4K | 27 | 12 | 15 | 10 | 1583# 16K | 27 | 14 | 13 | 11 | 1584# 64K | 29 | 16 | 13 | 13 | 1585config ARCH_FORCE_MAX_ORDER 1586 int 1587 default "13" if ARM64_64K_PAGES 1588 default "11" if ARM64_16K_PAGES 1589 default "10" 1590 help 1591 The kernel page allocator limits the size of maximal physically 1592 contiguous allocations. The limit is called MAX_ORDER and it 1593 defines the maximal power of two of number of pages that can be 1594 allocated as a single contiguous block. This option allows 1595 overriding the default setting when ability to allocate very 1596 large blocks of physically contiguous memory is required. 1597 1598 The maximal size of allocation cannot exceed the size of the 1599 section, so the value of MAX_ORDER should satisfy 1600 1601 MAX_ORDER + PAGE_SHIFT <= SECTION_SIZE_BITS 1602 1603 Don't change if unsure. 1604 1605config UNMAP_KERNEL_AT_EL0 1606 bool "Unmap kernel when running in userspace (aka \"KAISER\")" if EXPERT 1607 default y 1608 help 1609 Speculation attacks against some high-performance processors can 1610 be used to bypass MMU permission checks and leak kernel data to 1611 userspace. This can be defended against by unmapping the kernel 1612 when running in userspace, mapping it back in on exception entry 1613 via a trampoline page in the vector table. 1614 1615 If unsure, say Y. 1616 1617config MITIGATE_SPECTRE_BRANCH_HISTORY 1618 bool "Mitigate Spectre style attacks against branch history" if EXPERT 1619 default y 1620 help 1621 Speculation attacks against some high-performance processors can 1622 make use of branch history to influence future speculation. 1623 When taking an exception from user-space, a sequence of branches 1624 or a firmware call overwrites the branch history. 1625 1626config RODATA_FULL_DEFAULT_ENABLED 1627 bool "Apply r/o permissions of VM areas also to their linear aliases" 1628 default y 1629 help 1630 Apply read-only attributes of VM areas to the linear alias of 1631 the backing pages as well. This prevents code or read-only data 1632 from being modified (inadvertently or intentionally) via another 1633 mapping of the same memory page. This additional enhancement can 1634 be turned off at runtime by passing rodata=[off|on] (and turned on 1635 with rodata=full if this option is set to 'n') 1636 1637 This requires the linear region to be mapped down to pages, 1638 which may adversely affect performance in some cases. 1639 1640config ARM64_SW_TTBR0_PAN 1641 bool "Emulate Privileged Access Never using TTBR0_EL1 switching" 1642 help 1643 Enabling this option prevents the kernel from accessing 1644 user-space memory directly by pointing TTBR0_EL1 to a reserved 1645 zeroed area and reserved ASID. The user access routines 1646 restore the valid TTBR0_EL1 temporarily. 1647 1648config ARM64_TAGGED_ADDR_ABI 1649 bool "Enable the tagged user addresses syscall ABI" 1650 default y 1651 help 1652 When this option is enabled, user applications can opt in to a 1653 relaxed ABI via prctl() allowing tagged addresses to be passed 1654 to system calls as pointer arguments. For details, see 1655 Documentation/arch/arm64/tagged-address-abi.rst. 1656 1657menuconfig COMPAT 1658 bool "Kernel support for 32-bit EL0" 1659 depends on ARM64_4K_PAGES || EXPERT 1660 select HAVE_UID16 1661 select OLD_SIGSUSPEND3 1662 select COMPAT_OLD_SIGACTION 1663 help 1664 This option enables support for a 32-bit EL0 running under a 64-bit 1665 kernel at EL1. AArch32-specific components such as system calls, 1666 the user helper functions, VFP support and the ptrace interface are 1667 handled appropriately by the kernel. 1668 1669 If you use a page size other than 4KB (i.e, 16KB or 64KB), please be aware 1670 that you will only be able to execute AArch32 binaries that were compiled 1671 with page size aligned segments. 1672 1673 If you want to execute 32-bit userspace applications, say Y. 1674 1675if COMPAT 1676 1677config KUSER_HELPERS 1678 bool "Enable kuser helpers page for 32-bit applications" 1679 default y 1680 help 1681 Warning: disabling this option may break 32-bit user programs. 1682 1683 Provide kuser helpers to compat tasks. The kernel provides 1684 helper code to userspace in read only form at a fixed location 1685 to allow userspace to be independent of the CPU type fitted to 1686 the system. This permits binaries to be run on ARMv4 through 1687 to ARMv8 without modification. 1688 1689 See Documentation/arch/arm/kernel_user_helpers.rst for details. 1690 1691 However, the fixed address nature of these helpers can be used 1692 by ROP (return orientated programming) authors when creating 1693 exploits. 1694 1695 If all of the binaries and libraries which run on your platform 1696 are built specifically for your platform, and make no use of 1697 these helpers, then you can turn this option off to hinder 1698 such exploits. However, in that case, if a binary or library 1699 relying on those helpers is run, it will not function correctly. 1700 1701 Say N here only if you are absolutely certain that you do not 1702 need these helpers; otherwise, the safe option is to say Y. 1703 1704config COMPAT_VDSO 1705 bool "Enable vDSO for 32-bit applications" 1706 depends on !CPU_BIG_ENDIAN 1707 depends on (CC_IS_CLANG && LD_IS_LLD) || "$(CROSS_COMPILE_COMPAT)" != "" 1708 select GENERIC_COMPAT_VDSO 1709 default y 1710 help 1711 Place in the process address space of 32-bit applications an 1712 ELF shared object providing fast implementations of gettimeofday 1713 and clock_gettime. 1714 1715 You must have a 32-bit build of glibc 2.22 or later for programs 1716 to seamlessly take advantage of this. 1717 1718config THUMB2_COMPAT_VDSO 1719 bool "Compile the 32-bit vDSO for Thumb-2 mode" if EXPERT 1720 depends on COMPAT_VDSO 1721 default y 1722 help 1723 Compile the compat vDSO with '-mthumb -fomit-frame-pointer' if y, 1724 otherwise with '-marm'. 1725 1726config COMPAT_ALIGNMENT_FIXUPS 1727 bool "Fix up misaligned multi-word loads and stores in user space" 1728 1729menuconfig ARMV8_DEPRECATED 1730 bool "Emulate deprecated/obsolete ARMv8 instructions" 1731 depends on SYSCTL 1732 help 1733 Legacy software support may require certain instructions 1734 that have been deprecated or obsoleted in the architecture. 1735 1736 Enable this config to enable selective emulation of these 1737 features. 1738 1739 If unsure, say Y 1740 1741if ARMV8_DEPRECATED 1742 1743config SWP_EMULATION 1744 bool "Emulate SWP/SWPB instructions" 1745 help 1746 ARMv8 obsoletes the use of A32 SWP/SWPB instructions such that 1747 they are always undefined. Say Y here to enable software 1748 emulation of these instructions for userspace using LDXR/STXR. 1749 This feature can be controlled at runtime with the abi.swp 1750 sysctl which is disabled by default. 1751 1752 In some older versions of glibc [<=2.8] SWP is used during futex 1753 trylock() operations with the assumption that the code will not 1754 be preempted. This invalid assumption may be more likely to fail 1755 with SWP emulation enabled, leading to deadlock of the user 1756 application. 1757 1758 NOTE: when accessing uncached shared regions, LDXR/STXR rely 1759 on an external transaction monitoring block called a global 1760 monitor to maintain update atomicity. If your system does not 1761 implement a global monitor, this option can cause programs that 1762 perform SWP operations to uncached memory to deadlock. 1763 1764 If unsure, say Y 1765 1766config CP15_BARRIER_EMULATION 1767 bool "Emulate CP15 Barrier instructions" 1768 help 1769 The CP15 barrier instructions - CP15ISB, CP15DSB, and 1770 CP15DMB - are deprecated in ARMv8 (and ARMv7). It is 1771 strongly recommended to use the ISB, DSB, and DMB 1772 instructions instead. 1773 1774 Say Y here to enable software emulation of these 1775 instructions for AArch32 userspace code. When this option is 1776 enabled, CP15 barrier usage is traced which can help 1777 identify software that needs updating. This feature can be 1778 controlled at runtime with the abi.cp15_barrier sysctl. 1779 1780 If unsure, say Y 1781 1782config SETEND_EMULATION 1783 bool "Emulate SETEND instruction" 1784 help 1785 The SETEND instruction alters the data-endianness of the 1786 AArch32 EL0, and is deprecated in ARMv8. 1787 1788 Say Y here to enable software emulation of the instruction 1789 for AArch32 userspace code. This feature can be controlled 1790 at runtime with the abi.setend sysctl. 1791 1792 Note: All the cpus on the system must have mixed endian support at EL0 1793 for this feature to be enabled. If a new CPU - which doesn't support mixed 1794 endian - is hotplugged in after this feature has been enabled, there could 1795 be unexpected results in the applications. 1796 1797 If unsure, say Y 1798endif # ARMV8_DEPRECATED 1799 1800endif # COMPAT 1801 1802menu "ARMv8.1 architectural features" 1803 1804config ARM64_HW_AFDBM 1805 bool "Support for hardware updates of the Access and Dirty page flags" 1806 default y 1807 help 1808 The ARMv8.1 architecture extensions introduce support for 1809 hardware updates of the access and dirty information in page 1810 table entries. When enabled in TCR_EL1 (HA and HD bits) on 1811 capable processors, accesses to pages with PTE_AF cleared will 1812 set this bit instead of raising an access flag fault. 1813 Similarly, writes to read-only pages with the DBM bit set will 1814 clear the read-only bit (AP[2]) instead of raising a 1815 permission fault. 1816 1817 Kernels built with this configuration option enabled continue 1818 to work on pre-ARMv8.1 hardware and the performance impact is 1819 minimal. If unsure, say Y. 1820 1821config ARM64_PAN 1822 bool "Enable support for Privileged Access Never (PAN)" 1823 default y 1824 help 1825 Privileged Access Never (PAN; part of the ARMv8.1 Extensions) 1826 prevents the kernel or hypervisor from accessing user-space (EL0) 1827 memory directly. 1828 1829 Choosing this option will cause any unprotected (not using 1830 copy_to_user et al) memory access to fail with a permission fault. 1831 1832 The feature is detected at runtime, and will remain as a 'nop' 1833 instruction if the cpu does not implement the feature. 1834 1835config AS_HAS_LSE_ATOMICS 1836 def_bool $(as-instr,.arch_extension lse) 1837 1838config ARM64_LSE_ATOMICS 1839 bool 1840 default ARM64_USE_LSE_ATOMICS 1841 depends on AS_HAS_LSE_ATOMICS 1842 1843config ARM64_USE_LSE_ATOMICS 1844 bool "Atomic instructions" 1845 default y 1846 help 1847 As part of the Large System Extensions, ARMv8.1 introduces new 1848 atomic instructions that are designed specifically to scale in 1849 very large systems. 1850 1851 Say Y here to make use of these instructions for the in-kernel 1852 atomic routines. This incurs a small overhead on CPUs that do 1853 not support these instructions and requires the kernel to be 1854 built with binutils >= 2.25 in order for the new instructions 1855 to be used. 1856 1857endmenu # "ARMv8.1 architectural features" 1858 1859menu "ARMv8.2 architectural features" 1860 1861config AS_HAS_ARMV8_2 1862 def_bool $(cc-option,-Wa$(comma)-march=armv8.2-a) 1863 1864config AS_HAS_SHA3 1865 def_bool $(as-instr,.arch armv8.2-a+sha3) 1866 1867config ARM64_PMEM 1868 bool "Enable support for persistent memory" 1869 select ARCH_HAS_PMEM_API 1870 select ARCH_HAS_UACCESS_FLUSHCACHE 1871 help 1872 Say Y to enable support for the persistent memory API based on the 1873 ARMv8.2 DCPoP feature. 1874 1875 The feature is detected at runtime, and the kernel will use DC CVAC 1876 operations if DC CVAP is not supported (following the behaviour of 1877 DC CVAP itself if the system does not define a point of persistence). 1878 1879config ARM64_RAS_EXTN 1880 bool "Enable support for RAS CPU Extensions" 1881 default y 1882 help 1883 CPUs that support the Reliability, Availability and Serviceability 1884 (RAS) Extensions, part of ARMv8.2 are able to track faults and 1885 errors, classify them and report them to software. 1886 1887 On CPUs with these extensions system software can use additional 1888 barriers to determine if faults are pending and read the 1889 classification from a new set of registers. 1890 1891 Selecting this feature will allow the kernel to use these barriers 1892 and access the new registers if the system supports the extension. 1893 Platform RAS features may additionally depend on firmware support. 1894 1895config ARM64_CNP 1896 bool "Enable support for Common Not Private (CNP) translations" 1897 default y 1898 depends on ARM64_PAN || !ARM64_SW_TTBR0_PAN 1899 help 1900 Common Not Private (CNP) allows translation table entries to 1901 be shared between different PEs in the same inner shareable 1902 domain, so the hardware can use this fact to optimise the 1903 caching of such entries in the TLB. 1904 1905 Selecting this option allows the CNP feature to be detected 1906 at runtime, and does not affect PEs that do not implement 1907 this feature. 1908 1909endmenu # "ARMv8.2 architectural features" 1910 1911menu "ARMv8.3 architectural features" 1912 1913config ARM64_PTR_AUTH 1914 bool "Enable support for pointer authentication" 1915 default y 1916 help 1917 Pointer authentication (part of the ARMv8.3 Extensions) provides 1918 instructions for signing and authenticating pointers against secret 1919 keys, which can be used to mitigate Return Oriented Programming (ROP) 1920 and other attacks. 1921 1922 This option enables these instructions at EL0 (i.e. for userspace). 1923 Choosing this option will cause the kernel to initialise secret keys 1924 for each process at exec() time, with these keys being 1925 context-switched along with the process. 1926 1927 The feature is detected at runtime. If the feature is not present in 1928 hardware it will not be advertised to userspace/KVM guest nor will it 1929 be enabled. 1930 1931 If the feature is present on the boot CPU but not on a late CPU, then 1932 the late CPU will be parked. Also, if the boot CPU does not have 1933 address auth and the late CPU has then the late CPU will still boot 1934 but with the feature disabled. On such a system, this option should 1935 not be selected. 1936 1937config ARM64_PTR_AUTH_KERNEL 1938 bool "Use pointer authentication for kernel" 1939 default y 1940 depends on ARM64_PTR_AUTH 1941 depends on (CC_HAS_SIGN_RETURN_ADDRESS || CC_HAS_BRANCH_PROT_PAC_RET) && AS_HAS_ARMV8_3 1942 # Modern compilers insert a .note.gnu.property section note for PAC 1943 # which is only understood by binutils starting with version 2.33.1. 1944 depends on LD_IS_LLD || LD_VERSION >= 23301 || (CC_IS_GCC && GCC_VERSION < 90100) 1945 depends on !CC_IS_CLANG || AS_HAS_CFI_NEGATE_RA_STATE 1946 depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_ARGS) 1947 help 1948 If the compiler supports the -mbranch-protection or 1949 -msign-return-address flag (e.g. GCC 7 or later), then this option 1950 will cause the kernel itself to be compiled with return address 1951 protection. In this case, and if the target hardware is known to 1952 support pointer authentication, then CONFIG_STACKPROTECTOR can be 1953 disabled with minimal loss of protection. 1954 1955 This feature works with FUNCTION_GRAPH_TRACER option only if 1956 DYNAMIC_FTRACE_WITH_ARGS is enabled. 1957 1958config CC_HAS_BRANCH_PROT_PAC_RET 1959 # GCC 9 or later, clang 8 or later 1960 def_bool $(cc-option,-mbranch-protection=pac-ret+leaf) 1961 1962config CC_HAS_SIGN_RETURN_ADDRESS 1963 # GCC 7, 8 1964 def_bool $(cc-option,-msign-return-address=all) 1965 1966config AS_HAS_ARMV8_3 1967 def_bool $(cc-option,-Wa$(comma)-march=armv8.3-a) 1968 1969config AS_HAS_CFI_NEGATE_RA_STATE 1970 def_bool $(as-instr,.cfi_startproc\n.cfi_negate_ra_state\n.cfi_endproc\n) 1971 1972config AS_HAS_LDAPR 1973 def_bool $(as-instr,.arch_extension rcpc) 1974 1975endmenu # "ARMv8.3 architectural features" 1976 1977menu "ARMv8.4 architectural features" 1978 1979config ARM64_AMU_EXTN 1980 bool "Enable support for the Activity Monitors Unit CPU extension" 1981 default y 1982 help 1983 The activity monitors extension is an optional extension introduced 1984 by the ARMv8.4 CPU architecture. This enables support for version 1 1985 of the activity monitors architecture, AMUv1. 1986 1987 To enable the use of this extension on CPUs that implement it, say Y. 1988 1989 Note that for architectural reasons, firmware _must_ implement AMU 1990 support when running on CPUs that present the activity monitors 1991 extension. The required support is present in: 1992 * Version 1.5 and later of the ARM Trusted Firmware 1993 1994 For kernels that have this configuration enabled but boot with broken 1995 firmware, you may need to say N here until the firmware is fixed. 1996 Otherwise you may experience firmware panics or lockups when 1997 accessing the counter registers. Even if you are not observing these 1998 symptoms, the values returned by the register reads might not 1999 correctly reflect reality. Most commonly, the value read will be 0, 2000 indicating that the counter is not enabled. 2001 2002config AS_HAS_ARMV8_4 2003 def_bool $(cc-option,-Wa$(comma)-march=armv8.4-a) 2004 2005config ARM64_TLB_RANGE 2006 bool "Enable support for tlbi range feature" 2007 default y 2008 depends on AS_HAS_ARMV8_4 2009 help 2010 ARMv8.4-TLBI provides TLBI invalidation instruction that apply to a 2011 range of input addresses. 2012 2013 The feature introduces new assembly instructions, and they were 2014 support when binutils >= 2.30. 2015 2016endmenu # "ARMv8.4 architectural features" 2017 2018menu "ARMv8.5 architectural features" 2019 2020config AS_HAS_ARMV8_5 2021 def_bool $(cc-option,-Wa$(comma)-march=armv8.5-a) 2022 2023config ARM64_BTI 2024 bool "Branch Target Identification support" 2025 default y 2026 help 2027 Branch Target Identification (part of the ARMv8.5 Extensions) 2028 provides a mechanism to limit the set of locations to which computed 2029 branch instructions such as BR or BLR can jump. 2030 2031 To make use of BTI on CPUs that support it, say Y. 2032 2033 BTI is intended to provide complementary protection to other control 2034 flow integrity protection mechanisms, such as the Pointer 2035 authentication mechanism provided as part of the ARMv8.3 Extensions. 2036 For this reason, it does not make sense to enable this option without 2037 also enabling support for pointer authentication. Thus, when 2038 enabling this option you should also select ARM64_PTR_AUTH=y. 2039 2040 Userspace binaries must also be specifically compiled to make use of 2041 this mechanism. If you say N here or the hardware does not support 2042 BTI, such binaries can still run, but you get no additional 2043 enforcement of branch destinations. 2044 2045config ARM64_BTI_KERNEL 2046 bool "Use Branch Target Identification for kernel" 2047 default y 2048 depends on ARM64_BTI 2049 depends on ARM64_PTR_AUTH_KERNEL 2050 depends on CC_HAS_BRANCH_PROT_PAC_RET_BTI 2051 # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94697 2052 depends on !CC_IS_GCC || GCC_VERSION >= 100100 2053 # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106671 2054 depends on !CC_IS_GCC 2055 # https://github.com/llvm/llvm-project/commit/a88c722e687e6780dcd6a58718350dc76fcc4cc9 2056 depends on !CC_IS_CLANG || CLANG_VERSION >= 120000 2057 depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_ARGS) 2058 help 2059 Build the kernel with Branch Target Identification annotations 2060 and enable enforcement of this for kernel code. When this option 2061 is enabled and the system supports BTI all kernel code including 2062 modular code must have BTI enabled. 2063 2064config CC_HAS_BRANCH_PROT_PAC_RET_BTI 2065 # GCC 9 or later, clang 8 or later 2066 def_bool $(cc-option,-mbranch-protection=pac-ret+leaf+bti) 2067 2068config ARM64_E0PD 2069 bool "Enable support for E0PD" 2070 default y 2071 help 2072 E0PD (part of the ARMv8.5 extensions) allows us to ensure 2073 that EL0 accesses made via TTBR1 always fault in constant time, 2074 providing similar benefits to KASLR as those provided by KPTI, but 2075 with lower overhead and without disrupting legitimate access to 2076 kernel memory such as SPE. 2077 2078 This option enables E0PD for TTBR1 where available. 2079 2080config ARM64_AS_HAS_MTE 2081 # Initial support for MTE went in binutils 2.32.0, checked with 2082 # ".arch armv8.5-a+memtag" below. However, this was incomplete 2083 # as a late addition to the final architecture spec (LDGM/STGM) 2084 # is only supported in the newer 2.32.x and 2.33 binutils 2085 # versions, hence the extra "stgm" instruction check below. 2086 def_bool $(as-instr,.arch armv8.5-a+memtag\nstgm xzr$(comma)[x0]) 2087 2088config ARM64_MTE 2089 bool "Memory Tagging Extension support" 2090 default y 2091 depends on ARM64_AS_HAS_MTE && ARM64_TAGGED_ADDR_ABI 2092 depends on AS_HAS_ARMV8_5 2093 depends on AS_HAS_LSE_ATOMICS 2094 # Required for tag checking in the uaccess routines 2095 depends on ARM64_PAN 2096 select ARCH_HAS_SUBPAGE_FAULTS 2097 select ARCH_USES_HIGH_VMA_FLAGS 2098 select ARCH_USES_PG_ARCH_X 2099 help 2100 Memory Tagging (part of the ARMv8.5 Extensions) provides 2101 architectural support for run-time, always-on detection of 2102 various classes of memory error to aid with software debugging 2103 to eliminate vulnerabilities arising from memory-unsafe 2104 languages. 2105 2106 This option enables the support for the Memory Tagging 2107 Extension at EL0 (i.e. for userspace). 2108 2109 Selecting this option allows the feature to be detected at 2110 runtime. Any secondary CPU not implementing this feature will 2111 not be allowed a late bring-up. 2112 2113 Userspace binaries that want to use this feature must 2114 explicitly opt in. The mechanism for the userspace is 2115 described in: 2116 2117 Documentation/arch/arm64/memory-tagging-extension.rst. 2118 2119endmenu # "ARMv8.5 architectural features" 2120 2121menu "ARMv8.7 architectural features" 2122 2123config ARM64_EPAN 2124 bool "Enable support for Enhanced Privileged Access Never (EPAN)" 2125 default y 2126 depends on ARM64_PAN 2127 help 2128 Enhanced Privileged Access Never (EPAN) allows Privileged 2129 Access Never to be used with Execute-only mappings. 2130 2131 The feature is detected at runtime, and will remain disabled 2132 if the cpu does not implement the feature. 2133endmenu # "ARMv8.7 architectural features" 2134 2135config ARM64_SVE 2136 bool "ARM Scalable Vector Extension support" 2137 default y 2138 help 2139 The Scalable Vector Extension (SVE) is an extension to the AArch64 2140 execution state which complements and extends the SIMD functionality 2141 of the base architecture to support much larger vectors and to enable 2142 additional vectorisation opportunities. 2143 2144 To enable use of this extension on CPUs that implement it, say Y. 2145 2146 On CPUs that support the SVE2 extensions, this option will enable 2147 those too. 2148 2149 Note that for architectural reasons, firmware _must_ implement SVE 2150 support when running on SVE capable hardware. The required support 2151 is present in: 2152 2153 * version 1.5 and later of the ARM Trusted Firmware 2154 * the AArch64 boot wrapper since commit 5e1261e08abf 2155 ("bootwrapper: SVE: Enable SVE for EL2 and below"). 2156 2157 For other firmware implementations, consult the firmware documentation 2158 or vendor. 2159 2160 If you need the kernel to boot on SVE-capable hardware with broken 2161 firmware, you may need to say N here until you get your firmware 2162 fixed. Otherwise, you may experience firmware panics or lockups when 2163 booting the kernel. If unsure and you are not observing these 2164 symptoms, you should assume that it is safe to say Y. 2165 2166config ARM64_SME 2167 bool "ARM Scalable Matrix Extension support" 2168 default y 2169 depends on ARM64_SVE 2170 depends on BROKEN 2171 help 2172 The Scalable Matrix Extension (SME) is an extension to the AArch64 2173 execution state which utilises a substantial subset of the SVE 2174 instruction set, together with the addition of new architectural 2175 register state capable of holding two dimensional matrix tiles to 2176 enable various matrix operations. 2177 2178config ARM64_PSEUDO_NMI 2179 bool "Support for NMI-like interrupts" 2180 select ARM_GIC_V3 2181 help 2182 Adds support for mimicking Non-Maskable Interrupts through the use of 2183 GIC interrupt priority. This support requires version 3 or later of 2184 ARM GIC. 2185 2186 This high priority configuration for interrupts needs to be 2187 explicitly enabled by setting the kernel parameter 2188 "irqchip.gicv3_pseudo_nmi" to 1. 2189 2190 If unsure, say N 2191 2192if ARM64_PSEUDO_NMI 2193config ARM64_DEBUG_PRIORITY_MASKING 2194 bool "Debug interrupt priority masking" 2195 help 2196 This adds runtime checks to functions enabling/disabling 2197 interrupts when using priority masking. The additional checks verify 2198 the validity of ICC_PMR_EL1 when calling concerned functions. 2199 2200 If unsure, say N 2201endif # ARM64_PSEUDO_NMI 2202 2203config RELOCATABLE 2204 bool "Build a relocatable kernel image" if EXPERT 2205 select ARCH_HAS_RELR 2206 default y 2207 help 2208 This builds the kernel as a Position Independent Executable (PIE), 2209 which retains all relocation metadata required to relocate the 2210 kernel binary at runtime to a different virtual address than the 2211 address it was linked at. 2212 Since AArch64 uses the RELA relocation format, this requires a 2213 relocation pass at runtime even if the kernel is loaded at the 2214 same address it was linked at. 2215 2216config RANDOMIZE_BASE 2217 bool "Randomize the address of the kernel image" 2218 select RELOCATABLE 2219 help 2220 Randomizes the virtual address at which the kernel image is 2221 loaded, as a security feature that deters exploit attempts 2222 relying on knowledge of the location of kernel internals. 2223 2224 It is the bootloader's job to provide entropy, by passing a 2225 random u64 value in /chosen/kaslr-seed at kernel entry. 2226 2227 When booting via the UEFI stub, it will invoke the firmware's 2228 EFI_RNG_PROTOCOL implementation (if available) to supply entropy 2229 to the kernel proper. In addition, it will randomise the physical 2230 location of the kernel Image as well. 2231 2232 If unsure, say N. 2233 2234config RANDOMIZE_MODULE_REGION_FULL 2235 bool "Randomize the module region over a 2 GB range" 2236 depends on RANDOMIZE_BASE 2237 default y 2238 help 2239 Randomizes the location of the module region inside a 2 GB window 2240 covering the core kernel. This way, it is less likely for modules 2241 to leak information about the location of core kernel data structures 2242 but it does imply that function calls between modules and the core 2243 kernel will need to be resolved via veneers in the module PLT. 2244 2245 When this option is not set, the module region will be randomized over 2246 a limited range that contains the [_stext, _etext] interval of the 2247 core kernel, so branch relocations are almost always in range unless 2248 the region is exhausted. In this particular case of region 2249 exhaustion, modules might be able to fall back to a larger 2GB area. 2250 2251config CC_HAVE_STACKPROTECTOR_SYSREG 2252 def_bool $(cc-option,-mstack-protector-guard=sysreg -mstack-protector-guard-reg=sp_el0 -mstack-protector-guard-offset=0) 2253 2254config STACKPROTECTOR_PER_TASK 2255 def_bool y 2256 depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_SYSREG 2257 2258config UNWIND_PATCH_PAC_INTO_SCS 2259 bool "Enable shadow call stack dynamically using code patching" 2260 # needs Clang with https://reviews.llvm.org/D111780 incorporated 2261 depends on CC_IS_CLANG && CLANG_VERSION >= 150000 2262 depends on ARM64_PTR_AUTH_KERNEL && CC_HAS_BRANCH_PROT_PAC_RET 2263 depends on SHADOW_CALL_STACK 2264 select UNWIND_TABLES 2265 select DYNAMIC_SCS 2266 2267endmenu # "Kernel Features" 2268 2269menu "Boot options" 2270 2271config ARM64_ACPI_PARKING_PROTOCOL 2272 bool "Enable support for the ARM64 ACPI parking protocol" 2273 depends on ACPI 2274 help 2275 Enable support for the ARM64 ACPI parking protocol. If disabled 2276 the kernel will not allow booting through the ARM64 ACPI parking 2277 protocol even if the corresponding data is present in the ACPI 2278 MADT table. 2279 2280config CMDLINE 2281 string "Default kernel command string" 2282 default "" 2283 help 2284 Provide a set of default command-line options at build time by 2285 entering them here. As a minimum, you should specify the the 2286 root device (e.g. root=/dev/nfs). 2287 2288choice 2289 prompt "Kernel command line type" if CMDLINE != "" 2290 default CMDLINE_FROM_BOOTLOADER 2291 help 2292 Choose how the kernel will handle the provided default kernel 2293 command line string. 2294 2295config CMDLINE_FROM_BOOTLOADER 2296 bool "Use bootloader kernel arguments if available" 2297 help 2298 Uses the command-line options passed by the boot loader. If 2299 the boot loader doesn't provide any, the default kernel command 2300 string provided in CMDLINE will be used. 2301 2302config CMDLINE_FORCE 2303 bool "Always use the default kernel command string" 2304 help 2305 Always use the default kernel command string, even if the boot 2306 loader passes other arguments to the kernel. 2307 This is useful if you cannot or don't want to change the 2308 command-line options your boot loader passes to the kernel. 2309 2310endchoice 2311 2312config EFI_STUB 2313 bool 2314 2315config EFI 2316 bool "UEFI runtime support" 2317 depends on OF && !CPU_BIG_ENDIAN 2318 depends on KERNEL_MODE_NEON 2319 select ARCH_SUPPORTS_ACPI 2320 select LIBFDT 2321 select UCS2_STRING 2322 select EFI_PARAMS_FROM_FDT 2323 select EFI_RUNTIME_WRAPPERS 2324 select EFI_STUB 2325 select EFI_GENERIC_STUB 2326 imply IMA_SECURE_AND_OR_TRUSTED_BOOT 2327 default y 2328 help 2329 This option provides support for runtime services provided 2330 by UEFI firmware (such as non-volatile variables, realtime 2331 clock, and platform reset). A UEFI stub is also provided to 2332 allow the kernel to be booted as an EFI application. This 2333 is only useful on systems that have UEFI firmware. 2334 2335config DMI 2336 bool "Enable support for SMBIOS (DMI) tables" 2337 depends on EFI 2338 default y 2339 help 2340 This enables SMBIOS/DMI feature for systems. 2341 2342 This option is only useful on systems that have UEFI firmware. 2343 However, even with this option, the resultant kernel should 2344 continue to boot on existing non-UEFI platforms. 2345 2346endmenu # "Boot options" 2347 2348menu "Power management options" 2349 2350source "kernel/power/Kconfig" 2351 2352config ARCH_HIBERNATION_POSSIBLE 2353 def_bool y 2354 depends on CPU_PM 2355 2356config ARCH_HIBERNATION_HEADER 2357 def_bool y 2358 depends on HIBERNATION 2359 2360config ARCH_SUSPEND_POSSIBLE 2361 def_bool y 2362 2363endmenu # "Power management options" 2364 2365menu "CPU Power Management" 2366 2367source "drivers/cpuidle/Kconfig" 2368 2369source "drivers/cpufreq/Kconfig" 2370 2371endmenu # "CPU Power Management" 2372 2373source "drivers/acpi/Kconfig" 2374 2375source "arch/arm64/kvm/Kconfig" 2376 2377