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_USE_CMPXCHG_LOCKREF 82 select ARCH_USE_GNU_PROPERTY 83 select ARCH_USE_MEMTEST 84 select ARCH_USE_QUEUED_RWLOCKS 85 select ARCH_USE_QUEUED_SPINLOCKS 86 select ARCH_USE_SYM_ANNOTATIONS 87 select ARCH_SUPPORTS_DEBUG_PAGEALLOC 88 select ARCH_SUPPORTS_HUGETLBFS 89 select ARCH_SUPPORTS_MEMORY_FAILURE 90 select ARCH_SUPPORTS_SHADOW_CALL_STACK if CC_HAVE_SHADOW_CALL_STACK 91 select ARCH_SUPPORTS_LTO_CLANG if CPU_LITTLE_ENDIAN 92 select ARCH_SUPPORTS_LTO_CLANG_THIN 93 select ARCH_SUPPORTS_CFI_CLANG 94 select ARCH_SUPPORTS_ATOMIC_RMW 95 select ARCH_SUPPORTS_INT128 if CC_HAS_INT128 96 select ARCH_SUPPORTS_NUMA_BALANCING 97 select ARCH_SUPPORTS_PAGE_TABLE_CHECK 98 select ARCH_SUPPORTS_PER_VMA_LOCK 99 select ARCH_WANT_COMPAT_IPC_PARSE_VERSION if COMPAT 100 select ARCH_WANT_DEFAULT_BPF_JIT 101 select ARCH_WANT_DEFAULT_TOPDOWN_MMAP_LAYOUT 102 select ARCH_WANT_FRAME_POINTERS 103 select ARCH_WANT_HUGE_PMD_SHARE if ARM64_4K_PAGES || (ARM64_16K_PAGES && !ARM64_VA_BITS_36) 104 select ARCH_WANT_LD_ORPHAN_WARN 105 select ARCH_WANTS_NO_INSTR 106 select ARCH_WANTS_THP_SWAP if ARM64_4K_PAGES 107 select ARCH_HAS_UBSAN_SANITIZE_ALL 108 select ARM_AMBA 109 select ARM_ARCH_TIMER 110 select ARM_GIC 111 select AUDIT_ARCH_COMPAT_GENERIC 112 select ARM_GIC_V2M if PCI 113 select ARM_GIC_V3 114 select ARM_GIC_V3_ITS if PCI 115 select ARM_PSCI_FW 116 select BUILDTIME_TABLE_SORT 117 select CLONE_BACKWARDS 118 select COMMON_CLK 119 select CPU_PM if (SUSPEND || CPU_IDLE) 120 select CRC32 121 select DCACHE_WORD_ACCESS 122 select DYNAMIC_FTRACE if FUNCTION_TRACER 123 select DMA_DIRECT_REMAP 124 select EDAC_SUPPORT 125 select FRAME_POINTER 126 select FUNCTION_ALIGNMENT_4B 127 select FUNCTION_ALIGNMENT_8B if DYNAMIC_FTRACE_WITH_CALL_OPS 128 select GENERIC_ALLOCATOR 129 select GENERIC_ARCH_TOPOLOGY 130 select GENERIC_CLOCKEVENTS_BROADCAST 131 select GENERIC_CPU_AUTOPROBE 132 select GENERIC_CPU_VULNERABILITIES 133 select GENERIC_EARLY_IOREMAP 134 select GENERIC_IDLE_POLL_SETUP 135 select GENERIC_IOREMAP 136 select GENERIC_IRQ_IPI 137 select GENERIC_IRQ_PROBE 138 select GENERIC_IRQ_SHOW 139 select GENERIC_IRQ_SHOW_LEVEL 140 select GENERIC_LIB_DEVMEM_IS_ALLOWED 141 select GENERIC_PCI_IOMAP 142 select GENERIC_PTDUMP 143 select GENERIC_SCHED_CLOCK 144 select GENERIC_SMP_IDLE_THREAD 145 select GENERIC_TIME_VSYSCALL 146 select GENERIC_GETTIMEOFDAY 147 select GENERIC_VDSO_TIME_NS 148 select HARDIRQS_SW_RESEND 149 select HAS_IOPORT 150 select HAVE_MOVE_PMD 151 select HAVE_MOVE_PUD 152 select HAVE_PCI 153 select HAVE_ACPI_APEI if (ACPI && EFI) 154 select HAVE_ALIGNED_STRUCT_PAGE if SLUB 155 select HAVE_ARCH_AUDITSYSCALL 156 select HAVE_ARCH_BITREVERSE 157 select HAVE_ARCH_COMPILER_H 158 select HAVE_ARCH_HUGE_VMALLOC 159 select HAVE_ARCH_HUGE_VMAP 160 select HAVE_ARCH_JUMP_LABEL 161 select HAVE_ARCH_JUMP_LABEL_RELATIVE 162 select HAVE_ARCH_KASAN if !(ARM64_16K_PAGES && ARM64_VA_BITS_48) 163 select HAVE_ARCH_KASAN_VMALLOC if HAVE_ARCH_KASAN 164 select HAVE_ARCH_KASAN_SW_TAGS if HAVE_ARCH_KASAN 165 select HAVE_ARCH_KASAN_HW_TAGS if (HAVE_ARCH_KASAN && ARM64_MTE) 166 # Some instrumentation may be unsound, hence EXPERT 167 select HAVE_ARCH_KCSAN if EXPERT 168 select HAVE_ARCH_KFENCE 169 select HAVE_ARCH_KGDB 170 select HAVE_ARCH_MMAP_RND_BITS 171 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT 172 select HAVE_ARCH_PREL32_RELOCATIONS 173 select HAVE_ARCH_RANDOMIZE_KSTACK_OFFSET 174 select HAVE_ARCH_SECCOMP_FILTER 175 select HAVE_ARCH_STACKLEAK 176 select HAVE_ARCH_THREAD_STRUCT_WHITELIST 177 select HAVE_ARCH_TRACEHOOK 178 select HAVE_ARCH_TRANSPARENT_HUGEPAGE 179 select HAVE_ARCH_VMAP_STACK 180 select HAVE_ARM_SMCCC 181 select HAVE_ASM_MODVERSIONS 182 select HAVE_EBPF_JIT 183 select HAVE_C_RECORDMCOUNT 184 select HAVE_CMPXCHG_DOUBLE 185 select HAVE_CMPXCHG_LOCAL 186 select HAVE_CONTEXT_TRACKING_USER 187 select HAVE_DEBUG_KMEMLEAK 188 select HAVE_DMA_CONTIGUOUS 189 select HAVE_DYNAMIC_FTRACE 190 select HAVE_DYNAMIC_FTRACE_WITH_ARGS \ 191 if $(cc-option,-fpatchable-function-entry=2) 192 select HAVE_DYNAMIC_FTRACE_WITH_DIRECT_CALLS \ 193 if DYNAMIC_FTRACE_WITH_ARGS && DYNAMIC_FTRACE_WITH_CALL_OPS 194 select HAVE_DYNAMIC_FTRACE_WITH_CALL_OPS \ 195 if (DYNAMIC_FTRACE_WITH_ARGS && !CFI_CLANG && \ 196 !CC_OPTIMIZE_FOR_SIZE) 197 select FTRACE_MCOUNT_USE_PATCHABLE_FUNCTION_ENTRY \ 198 if DYNAMIC_FTRACE_WITH_ARGS 199 select HAVE_EFFICIENT_UNALIGNED_ACCESS 200 select HAVE_FAST_GUP 201 select HAVE_FTRACE_MCOUNT_RECORD 202 select HAVE_FUNCTION_TRACER 203 select HAVE_FUNCTION_ERROR_INJECTION 204 select HAVE_FUNCTION_GRAPH_TRACER 205 select HAVE_GCC_PLUGINS 206 select HAVE_HW_BREAKPOINT if PERF_EVENTS 207 select HAVE_IOREMAP_PROT 208 select HAVE_IRQ_TIME_ACCOUNTING 209 select HAVE_KVM 210 select HAVE_NMI 211 select HAVE_PERF_EVENTS 212 select HAVE_PERF_REGS 213 select HAVE_PERF_USER_STACK_DUMP 214 select HAVE_PREEMPT_DYNAMIC_KEY 215 select HAVE_REGS_AND_STACK_ACCESS_API 216 select HAVE_POSIX_CPU_TIMERS_TASK_WORK 217 select HAVE_FUNCTION_ARG_ACCESS_API 218 select MMU_GATHER_RCU_TABLE_FREE 219 select HAVE_RSEQ 220 select HAVE_STACKPROTECTOR 221 select HAVE_SYSCALL_TRACEPOINTS 222 select HAVE_KPROBES 223 select HAVE_KRETPROBES 224 select HAVE_GENERIC_VDSO 225 select IRQ_DOMAIN 226 select IRQ_FORCED_THREADING 227 select KASAN_VMALLOC if KASAN 228 select MODULES_USE_ELF_RELA 229 select NEED_DMA_MAP_STATE 230 select NEED_SG_DMA_LENGTH 231 select OF 232 select OF_EARLY_FLATTREE 233 select PCI_DOMAINS_GENERIC if PCI 234 select PCI_ECAM if (ACPI && PCI) 235 select PCI_SYSCALL if PCI 236 select POWER_RESET 237 select POWER_SUPPLY 238 select SPARSE_IRQ 239 select SWIOTLB 240 select SYSCTL_EXCEPTION_TRACE 241 select THREAD_INFO_IN_TASK 242 select HAVE_ARCH_USERFAULTFD_MINOR if USERFAULTFD 243 select TRACE_IRQFLAGS_SUPPORT 244 select TRACE_IRQFLAGS_NMI_SUPPORT 245 select HAVE_SOFTIRQ_ON_OWN_STACK 246 help 247 ARM 64-bit (AArch64) Linux support. 248 249config CLANG_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS 250 def_bool CC_IS_CLANG 251 # https://github.com/ClangBuiltLinux/linux/issues/1507 252 depends on AS_IS_GNU || (AS_IS_LLVM && (LD_IS_LLD || LD_VERSION >= 23600)) 253 select HAVE_DYNAMIC_FTRACE_WITH_ARGS 254 255config GCC_SUPPORTS_DYNAMIC_FTRACE_WITH_ARGS 256 def_bool CC_IS_GCC 257 depends on $(cc-option,-fpatchable-function-entry=2) 258 select HAVE_DYNAMIC_FTRACE_WITH_ARGS 259 260config 64BIT 261 def_bool y 262 263config MMU 264 def_bool y 265 266config ARM64_PAGE_SHIFT 267 int 268 default 16 if ARM64_64K_PAGES 269 default 14 if ARM64_16K_PAGES 270 default 12 271 272config ARM64_CONT_PTE_SHIFT 273 int 274 default 5 if ARM64_64K_PAGES 275 default 7 if ARM64_16K_PAGES 276 default 4 277 278config ARM64_CONT_PMD_SHIFT 279 int 280 default 5 if ARM64_64K_PAGES 281 default 5 if ARM64_16K_PAGES 282 default 4 283 284config ARCH_MMAP_RND_BITS_MIN 285 default 14 if ARM64_64K_PAGES 286 default 16 if ARM64_16K_PAGES 287 default 18 288 289# max bits determined by the following formula: 290# VA_BITS - PAGE_SHIFT - 3 291config ARCH_MMAP_RND_BITS_MAX 292 default 19 if ARM64_VA_BITS=36 293 default 24 if ARM64_VA_BITS=39 294 default 27 if ARM64_VA_BITS=42 295 default 30 if ARM64_VA_BITS=47 296 default 29 if ARM64_VA_BITS=48 && ARM64_64K_PAGES 297 default 31 if ARM64_VA_BITS=48 && ARM64_16K_PAGES 298 default 33 if ARM64_VA_BITS=48 299 default 14 if ARM64_64K_PAGES 300 default 16 if ARM64_16K_PAGES 301 default 18 302 303config ARCH_MMAP_RND_COMPAT_BITS_MIN 304 default 7 if ARM64_64K_PAGES 305 default 9 if ARM64_16K_PAGES 306 default 11 307 308config ARCH_MMAP_RND_COMPAT_BITS_MAX 309 default 16 310 311config NO_IOPORT_MAP 312 def_bool y if !PCI 313 314config STACKTRACE_SUPPORT 315 def_bool y 316 317config ILLEGAL_POINTER_VALUE 318 hex 319 default 0xdead000000000000 320 321config LOCKDEP_SUPPORT 322 def_bool y 323 324config GENERIC_BUG 325 def_bool y 326 depends on BUG 327 328config GENERIC_BUG_RELATIVE_POINTERS 329 def_bool y 330 depends on GENERIC_BUG 331 332config GENERIC_HWEIGHT 333 def_bool y 334 335config GENERIC_CSUM 336 def_bool y 337 338config GENERIC_CALIBRATE_DELAY 339 def_bool y 340 341config ARCH_MHP_MEMMAP_ON_MEMORY_ENABLE 342 def_bool y 343 344config SMP 345 def_bool y 346 347config KERNEL_MODE_NEON 348 def_bool y 349 350config FIX_EARLYCON_MEM 351 def_bool y 352 353config PGTABLE_LEVELS 354 int 355 default 2 if ARM64_16K_PAGES && ARM64_VA_BITS_36 356 default 2 if ARM64_64K_PAGES && ARM64_VA_BITS_42 357 default 3 if ARM64_64K_PAGES && (ARM64_VA_BITS_48 || ARM64_VA_BITS_52) 358 default 3 if ARM64_4K_PAGES && ARM64_VA_BITS_39 359 default 3 if ARM64_16K_PAGES && ARM64_VA_BITS_47 360 default 4 if !ARM64_64K_PAGES && ARM64_VA_BITS_48 361 362config ARCH_SUPPORTS_UPROBES 363 def_bool y 364 365config ARCH_PROC_KCORE_TEXT 366 def_bool y 367 368config BROKEN_GAS_INST 369 def_bool !$(as-instr,1:\n.inst 0\n.rept . - 1b\n\nnop\n.endr\n) 370 371config BUILTIN_RETURN_ADDRESS_STRIPS_PAC 372 bool 373 # Clang's __builtin_return_adddress() strips the PAC since 12.0.0 374 # https://reviews.llvm.org/D75044 375 default y if CC_IS_CLANG && (CLANG_VERSION >= 120000) 376 # GCC's __builtin_return_address() strips the PAC since 11.1.0, 377 # and this was backported to 10.2.0, 9.4.0, 8.5.0, but not earlier 378 # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94891 379 default y if CC_IS_GCC && (GCC_VERSION >= 110100) 380 default y if CC_IS_GCC && (GCC_VERSION >= 100200) && (GCC_VERSION < 110000) 381 default y if CC_IS_GCC && (GCC_VERSION >= 90400) && (GCC_VERSION < 100000) 382 default y if CC_IS_GCC && (GCC_VERSION >= 80500) && (GCC_VERSION < 90000) 383 default n 384 385config KASAN_SHADOW_OFFSET 386 hex 387 depends on KASAN_GENERIC || KASAN_SW_TAGS 388 default 0xdfff800000000000 if (ARM64_VA_BITS_48 || ARM64_VA_BITS_52) && !KASAN_SW_TAGS 389 default 0xdfffc00000000000 if ARM64_VA_BITS_47 && !KASAN_SW_TAGS 390 default 0xdffffe0000000000 if ARM64_VA_BITS_42 && !KASAN_SW_TAGS 391 default 0xdfffffc000000000 if ARM64_VA_BITS_39 && !KASAN_SW_TAGS 392 default 0xdffffff800000000 if ARM64_VA_BITS_36 && !KASAN_SW_TAGS 393 default 0xefff800000000000 if (ARM64_VA_BITS_48 || ARM64_VA_BITS_52) && KASAN_SW_TAGS 394 default 0xefffc00000000000 if ARM64_VA_BITS_47 && KASAN_SW_TAGS 395 default 0xeffffe0000000000 if ARM64_VA_BITS_42 && KASAN_SW_TAGS 396 default 0xefffffc000000000 if ARM64_VA_BITS_39 && KASAN_SW_TAGS 397 default 0xeffffff800000000 if ARM64_VA_BITS_36 && KASAN_SW_TAGS 398 default 0xffffffffffffffff 399 400config UNWIND_TABLES 401 bool 402 403source "arch/arm64/Kconfig.platforms" 404 405menu "Kernel Features" 406 407menu "ARM errata workarounds via the alternatives framework" 408 409config AMPERE_ERRATUM_AC03_CPU_38 410 bool "AmpereOne: AC03_CPU_38: Certain bits in the Virtualization Translation Control Register and Translation Control Registers do not follow RES0 semantics" 411 default y 412 help 413 This option adds an alternative code sequence to work around Ampere 414 erratum AC03_CPU_38 on AmpereOne. 415 416 The affected design reports FEAT_HAFDBS as not implemented in 417 ID_AA64MMFR1_EL1.HAFDBS, but (V)TCR_ELx.{HA,HD} are not RES0 418 as required by the architecture. The unadvertised HAFDBS 419 implementation suffers from an additional erratum where hardware 420 A/D updates can occur after a PTE has been marked invalid. 421 422 The workaround forces KVM to explicitly set VTCR_EL2.HA to 0, 423 which avoids enabling unadvertised hardware Access Flag management 424 at stage-2. 425 426 If unsure, say Y. 427 428config ARM64_WORKAROUND_CLEAN_CACHE 429 bool 430 431config ARM64_ERRATUM_826319 432 bool "Cortex-A53: 826319: System might deadlock if a write cannot complete until read data is accepted" 433 default y 434 select ARM64_WORKAROUND_CLEAN_CACHE 435 help 436 This option adds an alternative code sequence to work around ARM 437 erratum 826319 on Cortex-A53 parts up to r0p2 with an AMBA 4 ACE or 438 AXI master interface and an L2 cache. 439 440 If a Cortex-A53 uses an AMBA AXI4 ACE interface to other processors 441 and is unable to accept a certain write via this interface, it will 442 not progress on read data presented on the read data channel and the 443 system can deadlock. 444 445 The workaround promotes data cache clean instructions to 446 data cache clean-and-invalidate. 447 Please note that this does not necessarily enable the workaround, 448 as it depends on the alternative framework, which will only patch 449 the kernel if an affected CPU is detected. 450 451 If unsure, say Y. 452 453config ARM64_ERRATUM_827319 454 bool "Cortex-A53: 827319: Data cache clean instructions might cause overlapping transactions to the interconnect" 455 default y 456 select ARM64_WORKAROUND_CLEAN_CACHE 457 help 458 This option adds an alternative code sequence to work around ARM 459 erratum 827319 on Cortex-A53 parts up to r0p2 with an AMBA 5 CHI 460 master interface and an L2 cache. 461 462 Under certain conditions this erratum can cause a clean line eviction 463 to occur at the same time as another transaction to the same address 464 on the AMBA 5 CHI interface, which can cause data corruption if the 465 interconnect reorders the two transactions. 466 467 The workaround promotes data cache clean instructions to 468 data cache clean-and-invalidate. 469 Please note that this does not necessarily enable the workaround, 470 as it depends on the alternative framework, which will only patch 471 the kernel if an affected CPU is detected. 472 473 If unsure, say Y. 474 475config ARM64_ERRATUM_824069 476 bool "Cortex-A53: 824069: Cache line might not be marked as clean after a CleanShared snoop" 477 default y 478 select ARM64_WORKAROUND_CLEAN_CACHE 479 help 480 This option adds an alternative code sequence to work around ARM 481 erratum 824069 on Cortex-A53 parts up to r0p2 when it is connected 482 to a coherent interconnect. 483 484 If a Cortex-A53 processor is executing a store or prefetch for 485 write instruction at the same time as a processor in another 486 cluster is executing a cache maintenance operation to the same 487 address, then this erratum might cause a clean cache line to be 488 incorrectly marked as dirty. 489 490 The workaround promotes data cache clean instructions to 491 data cache clean-and-invalidate. 492 Please note that this option does not necessarily enable the 493 workaround, as it depends on the alternative framework, which will 494 only patch the kernel if an affected CPU is detected. 495 496 If unsure, say Y. 497 498config ARM64_ERRATUM_819472 499 bool "Cortex-A53: 819472: Store exclusive instructions might cause data corruption" 500 default y 501 select ARM64_WORKAROUND_CLEAN_CACHE 502 help 503 This option adds an alternative code sequence to work around ARM 504 erratum 819472 on Cortex-A53 parts up to r0p1 with an L2 cache 505 present when it is connected to a coherent interconnect. 506 507 If the processor is executing a load and store exclusive sequence at 508 the same time as a processor in another cluster is executing a cache 509 maintenance operation to the same address, then this erratum might 510 cause data corruption. 511 512 The workaround promotes data cache clean instructions to 513 data cache clean-and-invalidate. 514 Please note that this does not necessarily enable the workaround, 515 as it depends on the alternative framework, which will only patch 516 the kernel if an affected CPU is detected. 517 518 If unsure, say Y. 519 520config ARM64_ERRATUM_832075 521 bool "Cortex-A57: 832075: possible deadlock on mixing exclusive memory accesses with device loads" 522 default y 523 help 524 This option adds an alternative code sequence to work around ARM 525 erratum 832075 on Cortex-A57 parts up to r1p2. 526 527 Affected Cortex-A57 parts might deadlock when exclusive load/store 528 instructions to Write-Back memory are mixed with Device loads. 529 530 The workaround is to promote device loads to use Load-Acquire 531 semantics. 532 Please note that this does not necessarily enable the workaround, 533 as it depends on the alternative framework, which will only patch 534 the kernel if an affected CPU is detected. 535 536 If unsure, say Y. 537 538config ARM64_ERRATUM_834220 539 bool "Cortex-A57: 834220: Stage 2 translation fault might be incorrectly reported in presence of a Stage 1 fault" 540 depends on KVM 541 default y 542 help 543 This option adds an alternative code sequence to work around ARM 544 erratum 834220 on Cortex-A57 parts up to r1p2. 545 546 Affected Cortex-A57 parts might report a Stage 2 translation 547 fault as the result of a Stage 1 fault for load crossing a 548 page boundary when there is a permission or device memory 549 alignment fault at Stage 1 and a translation fault at Stage 2. 550 551 The workaround is to verify that the Stage 1 translation 552 doesn't generate a fault before handling the Stage 2 fault. 553 Please note that this does not necessarily enable the workaround, 554 as it depends on the alternative framework, which will only patch 555 the kernel if an affected CPU is detected. 556 557 If unsure, say Y. 558 559config ARM64_ERRATUM_1742098 560 bool "Cortex-A57/A72: 1742098: ELR recorded incorrectly on interrupt taken between cryptographic instructions in a sequence" 561 depends on COMPAT 562 default y 563 help 564 This option removes the AES hwcap for aarch32 user-space to 565 workaround erratum 1742098 on Cortex-A57 and Cortex-A72. 566 567 Affected parts may corrupt the AES state if an interrupt is 568 taken between a pair of AES instructions. These instructions 569 are only present if the cryptography extensions are present. 570 All software should have a fallback implementation for CPUs 571 that don't implement the cryptography extensions. 572 573 If unsure, say Y. 574 575config ARM64_ERRATUM_845719 576 bool "Cortex-A53: 845719: a load might read incorrect data" 577 depends on COMPAT 578 default y 579 help 580 This option adds an alternative code sequence to work around ARM 581 erratum 845719 on Cortex-A53 parts up to r0p4. 582 583 When running a compat (AArch32) userspace on an affected Cortex-A53 584 part, a load at EL0 from a virtual address that matches the bottom 32 585 bits of the virtual address used by a recent load at (AArch64) EL1 586 might return incorrect data. 587 588 The workaround is to write the contextidr_el1 register on exception 589 return to a 32-bit task. 590 Please note that this does not necessarily enable the workaround, 591 as it depends on the alternative framework, which will only patch 592 the kernel if an affected CPU is detected. 593 594 If unsure, say Y. 595 596config ARM64_ERRATUM_843419 597 bool "Cortex-A53: 843419: A load or store might access an incorrect address" 598 default y 599 select ARM64_MODULE_PLTS if MODULES 600 help 601 This option links the kernel with '--fix-cortex-a53-843419' and 602 enables PLT support to replace certain ADRP instructions, which can 603 cause subsequent memory accesses to use an incorrect address on 604 Cortex-A53 parts up to r0p4. 605 606 If unsure, say Y. 607 608config ARM64_LD_HAS_FIX_ERRATUM_843419 609 def_bool $(ld-option,--fix-cortex-a53-843419) 610 611config ARM64_ERRATUM_1024718 612 bool "Cortex-A55: 1024718: Update of DBM/AP bits without break before make might result in incorrect update" 613 default y 614 help 615 This option adds a workaround for ARM Cortex-A55 Erratum 1024718. 616 617 Affected Cortex-A55 cores (all revisions) could cause incorrect 618 update of the hardware dirty bit when the DBM/AP bits are updated 619 without a break-before-make. The workaround is to disable the usage 620 of hardware DBM locally on the affected cores. CPUs not affected by 621 this erratum will continue to use the feature. 622 623 If unsure, say Y. 624 625config ARM64_ERRATUM_1418040 626 bool "Cortex-A76/Neoverse-N1: MRC read following MRRC read of specific Generic Timer in AArch32 might give incorrect result" 627 default y 628 depends on COMPAT 629 help 630 This option adds a workaround for ARM Cortex-A76/Neoverse-N1 631 errata 1188873 and 1418040. 632 633 Affected Cortex-A76/Neoverse-N1 cores (r0p0 to r3p1) could 634 cause register corruption when accessing the timer registers 635 from AArch32 userspace. 636 637 If unsure, say Y. 638 639config ARM64_WORKAROUND_SPECULATIVE_AT 640 bool 641 642config ARM64_ERRATUM_1165522 643 bool "Cortex-A76: 1165522: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation" 644 default y 645 select ARM64_WORKAROUND_SPECULATIVE_AT 646 help 647 This option adds a workaround for ARM Cortex-A76 erratum 1165522. 648 649 Affected Cortex-A76 cores (r0p0, r1p0, r2p0) could end-up with 650 corrupted TLBs by speculating an AT instruction during a guest 651 context switch. 652 653 If unsure, say Y. 654 655config ARM64_ERRATUM_1319367 656 bool "Cortex-A57/A72: 1319537: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation" 657 default y 658 select ARM64_WORKAROUND_SPECULATIVE_AT 659 help 660 This option adds work arounds for ARM Cortex-A57 erratum 1319537 661 and A72 erratum 1319367 662 663 Cortex-A57 and A72 cores could end-up with corrupted TLBs by 664 speculating an AT instruction during a guest context switch. 665 666 If unsure, say Y. 667 668config ARM64_ERRATUM_1530923 669 bool "Cortex-A55: 1530923: Speculative AT instruction using out-of-context translation regime could cause subsequent request to generate an incorrect translation" 670 default y 671 select ARM64_WORKAROUND_SPECULATIVE_AT 672 help 673 This option adds a workaround for ARM Cortex-A55 erratum 1530923. 674 675 Affected Cortex-A55 cores (r0p0, r0p1, r1p0, r2p0) could end-up with 676 corrupted TLBs by speculating an AT instruction during a guest 677 context switch. 678 679 If unsure, say Y. 680 681config ARM64_WORKAROUND_REPEAT_TLBI 682 bool 683 684config ARM64_ERRATUM_2441007 685 bool "Cortex-A55: Completion of affected memory accesses might not be guaranteed by completion of a TLBI" 686 default y 687 select ARM64_WORKAROUND_REPEAT_TLBI 688 help 689 This option adds a workaround for ARM Cortex-A55 erratum #2441007. 690 691 Under very rare circumstances, affected Cortex-A55 CPUs 692 may not handle a race between a break-before-make sequence on one 693 CPU, and another CPU accessing the same page. This could allow a 694 store to a page that has been unmapped. 695 696 Work around this by adding the affected CPUs to the list that needs 697 TLB sequences to be done twice. 698 699 If unsure, say Y. 700 701config ARM64_ERRATUM_1286807 702 bool "Cortex-A76: Modification of the translation table for a virtual address might lead to read-after-read ordering violation" 703 default y 704 select ARM64_WORKAROUND_REPEAT_TLBI 705 help 706 This option adds a workaround for ARM Cortex-A76 erratum 1286807. 707 708 On the affected Cortex-A76 cores (r0p0 to r3p0), if a virtual 709 address for a cacheable mapping of a location is being 710 accessed by a core while another core is remapping the virtual 711 address to a new physical page using the recommended 712 break-before-make sequence, then under very rare circumstances 713 TLBI+DSB completes before a read using the translation being 714 invalidated has been observed by other observers. The 715 workaround repeats the TLBI+DSB operation. 716 717config ARM64_ERRATUM_1463225 718 bool "Cortex-A76: Software Step might prevent interrupt recognition" 719 default y 720 help 721 This option adds a workaround for Arm Cortex-A76 erratum 1463225. 722 723 On the affected Cortex-A76 cores (r0p0 to r3p1), software stepping 724 of a system call instruction (SVC) can prevent recognition of 725 subsequent interrupts when software stepping is disabled in the 726 exception handler of the system call and either kernel debugging 727 is enabled or VHE is in use. 728 729 Work around the erratum by triggering a dummy step exception 730 when handling a system call from a task that is being stepped 731 in a VHE configuration of the kernel. 732 733 If unsure, say Y. 734 735config ARM64_ERRATUM_1542419 736 bool "Neoverse-N1: workaround mis-ordering of instruction fetches" 737 default y 738 help 739 This option adds a workaround for ARM Neoverse-N1 erratum 740 1542419. 741 742 Affected Neoverse-N1 cores could execute a stale instruction when 743 modified by another CPU. The workaround depends on a firmware 744 counterpart. 745 746 Workaround the issue by hiding the DIC feature from EL0. This 747 forces user-space to perform cache maintenance. 748 749 If unsure, say Y. 750 751config ARM64_ERRATUM_1508412 752 bool "Cortex-A77: 1508412: workaround deadlock on sequence of NC/Device load and store exclusive or PAR read" 753 default y 754 help 755 This option adds a workaround for Arm Cortex-A77 erratum 1508412. 756 757 Affected Cortex-A77 cores (r0p0, r1p0) could deadlock on a sequence 758 of a store-exclusive or read of PAR_EL1 and a load with device or 759 non-cacheable memory attributes. The workaround depends on a firmware 760 counterpart. 761 762 KVM guests must also have the workaround implemented or they can 763 deadlock the system. 764 765 Work around the issue by inserting DMB SY barriers around PAR_EL1 766 register reads and warning KVM users. The DMB barrier is sufficient 767 to prevent a speculative PAR_EL1 read. 768 769 If unsure, say Y. 770 771config ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE 772 bool 773 774config ARM64_ERRATUM_2051678 775 bool "Cortex-A510: 2051678: disable Hardware Update of the page table dirty bit" 776 default y 777 help 778 This options adds the workaround for ARM Cortex-A510 erratum ARM64_ERRATUM_2051678. 779 Affected Cortex-A510 might not respect the ordering rules for 780 hardware update of the page table's dirty bit. The workaround 781 is to not enable the feature on affected CPUs. 782 783 If unsure, say Y. 784 785config ARM64_ERRATUM_2077057 786 bool "Cortex-A510: 2077057: workaround software-step corrupting SPSR_EL2" 787 default y 788 help 789 This option adds the workaround for ARM Cortex-A510 erratum 2077057. 790 Affected Cortex-A510 may corrupt SPSR_EL2 when the a step exception is 791 expected, but a Pointer Authentication trap is taken instead. The 792 erratum causes SPSR_EL1 to be copied to SPSR_EL2, which could allow 793 EL1 to cause a return to EL2 with a guest controlled ELR_EL2. 794 795 This can only happen when EL2 is stepping EL1. 796 797 When these conditions occur, the SPSR_EL2 value is unchanged from the 798 previous guest entry, and can be restored from the in-memory copy. 799 800 If unsure, say Y. 801 802config ARM64_ERRATUM_2658417 803 bool "Cortex-A510: 2658417: remove BF16 support due to incorrect result" 804 default y 805 help 806 This option adds the workaround for ARM Cortex-A510 erratum 2658417. 807 Affected Cortex-A510 (r0p0 to r1p1) may produce the wrong result for 808 BFMMLA or VMMLA instructions in rare circumstances when a pair of 809 A510 CPUs are using shared neon hardware. As the sharing is not 810 discoverable by the kernel, hide the BF16 HWCAP to indicate that 811 user-space should not be using these instructions. 812 813 If unsure, say Y. 814 815config ARM64_ERRATUM_2119858 816 bool "Cortex-A710/X2: 2119858: workaround TRBE overwriting trace data in FILL mode" 817 default y 818 depends on CORESIGHT_TRBE 819 select ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE 820 help 821 This option adds the workaround for ARM Cortex-A710/X2 erratum 2119858. 822 823 Affected Cortex-A710/X2 cores could overwrite up to 3 cache lines of trace 824 data at the base of the buffer (pointed to by TRBASER_EL1) in FILL mode in 825 the event of a WRAP event. 826 827 Work around the issue by always making sure we move the TRBPTR_EL1 by 828 256 bytes before enabling the buffer and filling the first 256 bytes of 829 the buffer with ETM ignore packets upon disabling. 830 831 If unsure, say Y. 832 833config ARM64_ERRATUM_2139208 834 bool "Neoverse-N2: 2139208: workaround TRBE overwriting trace data in FILL mode" 835 default y 836 depends on CORESIGHT_TRBE 837 select ARM64_WORKAROUND_TRBE_OVERWRITE_FILL_MODE 838 help 839 This option adds the workaround for ARM Neoverse-N2 erratum 2139208. 840 841 Affected Neoverse-N2 cores could overwrite up to 3 cache lines of trace 842 data at the base of the buffer (pointed to by TRBASER_EL1) in FILL mode in 843 the event of a WRAP event. 844 845 Work around the issue by always making sure we move the TRBPTR_EL1 by 846 256 bytes before enabling the buffer and filling the first 256 bytes of 847 the buffer with ETM ignore packets upon disabling. 848 849 If unsure, say Y. 850 851config ARM64_WORKAROUND_TSB_FLUSH_FAILURE 852 bool 853 854config ARM64_ERRATUM_2054223 855 bool "Cortex-A710: 2054223: workaround TSB instruction failing to flush trace" 856 default y 857 select ARM64_WORKAROUND_TSB_FLUSH_FAILURE 858 help 859 Enable workaround for ARM Cortex-A710 erratum 2054223 860 861 Affected cores may fail to flush the trace data on a TSB instruction, when 862 the PE is in trace prohibited state. This will cause losing a few bytes 863 of the trace cached. 864 865 Workaround is to issue two TSB consecutively on affected cores. 866 867 If unsure, say Y. 868 869config ARM64_ERRATUM_2067961 870 bool "Neoverse-N2: 2067961: workaround TSB instruction failing to flush trace" 871 default y 872 select ARM64_WORKAROUND_TSB_FLUSH_FAILURE 873 help 874 Enable workaround for ARM Neoverse-N2 erratum 2067961 875 876 Affected cores may fail to flush the trace data on a TSB instruction, when 877 the PE is in trace prohibited state. This will cause losing a few bytes 878 of the trace cached. 879 880 Workaround is to issue two TSB consecutively on affected cores. 881 882 If unsure, say Y. 883 884config ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE 885 bool 886 887config ARM64_ERRATUM_2253138 888 bool "Neoverse-N2: 2253138: workaround TRBE writing to address out-of-range" 889 depends on CORESIGHT_TRBE 890 default y 891 select ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE 892 help 893 This option adds the workaround for ARM Neoverse-N2 erratum 2253138. 894 895 Affected Neoverse-N2 cores might write to an out-of-range address, not reserved 896 for TRBE. Under some conditions, the TRBE might generate a write to the next 897 virtually addressed page following the last page of the TRBE address space 898 (i.e., the TRBLIMITR_EL1.LIMIT), instead of wrapping around to the base. 899 900 Work around this in the driver by always making sure that there is a 901 page beyond the TRBLIMITR_EL1.LIMIT, within the space allowed for the TRBE. 902 903 If unsure, say Y. 904 905config ARM64_ERRATUM_2224489 906 bool "Cortex-A710/X2: 2224489: workaround TRBE writing to address out-of-range" 907 depends on CORESIGHT_TRBE 908 default y 909 select ARM64_WORKAROUND_TRBE_WRITE_OUT_OF_RANGE 910 help 911 This option adds the workaround for ARM Cortex-A710/X2 erratum 2224489. 912 913 Affected Cortex-A710/X2 cores might write to an out-of-range address, not reserved 914 for TRBE. Under some conditions, the TRBE might generate a write to the next 915 virtually addressed page following the last page of the TRBE address space 916 (i.e., the TRBLIMITR_EL1.LIMIT), instead of wrapping around to the base. 917 918 Work around this in the driver by always making sure that there is a 919 page beyond the TRBLIMITR_EL1.LIMIT, within the space allowed for the TRBE. 920 921 If unsure, say Y. 922 923config ARM64_ERRATUM_2441009 924 bool "Cortex-A510: Completion of affected memory accesses might not be guaranteed by completion of a TLBI" 925 default y 926 select ARM64_WORKAROUND_REPEAT_TLBI 927 help 928 This option adds a workaround for ARM Cortex-A510 erratum #2441009. 929 930 Under very rare circumstances, affected Cortex-A510 CPUs 931 may not handle a race between a break-before-make sequence on one 932 CPU, and another CPU accessing the same page. This could allow a 933 store to a page that has been unmapped. 934 935 Work around this by adding the affected CPUs to the list that needs 936 TLB sequences to be done twice. 937 938 If unsure, say Y. 939 940config ARM64_ERRATUM_2064142 941 bool "Cortex-A510: 2064142: workaround TRBE register writes while disabled" 942 depends on CORESIGHT_TRBE 943 default y 944 help 945 This option adds the workaround for ARM Cortex-A510 erratum 2064142. 946 947 Affected Cortex-A510 core might fail to write into system registers after the 948 TRBE has been disabled. Under some conditions after the TRBE has been disabled 949 writes into TRBE registers TRBLIMITR_EL1, TRBPTR_EL1, TRBBASER_EL1, TRBSR_EL1, 950 and TRBTRG_EL1 will be ignored and will not be effected. 951 952 Work around this in the driver by executing TSB CSYNC and DSB after collection 953 is stopped and before performing a system register write to one of the affected 954 registers. 955 956 If unsure, say Y. 957 958config ARM64_ERRATUM_2038923 959 bool "Cortex-A510: 2038923: workaround TRBE corruption with enable" 960 depends on CORESIGHT_TRBE 961 default y 962 help 963 This option adds the workaround for ARM Cortex-A510 erratum 2038923. 964 965 Affected Cortex-A510 core might cause an inconsistent view on whether trace is 966 prohibited within the CPU. As a result, the trace buffer or trace buffer state 967 might be corrupted. This happens after TRBE buffer has been enabled by setting 968 TRBLIMITR_EL1.E, followed by just a single context synchronization event before 969 execution changes from a context, in which trace is prohibited to one where it 970 isn't, or vice versa. In these mentioned conditions, the view of whether trace 971 is prohibited is inconsistent between parts of the CPU, and the trace buffer or 972 the trace buffer state might be corrupted. 973 974 Work around this in the driver by preventing an inconsistent view of whether the 975 trace is prohibited or not based on TRBLIMITR_EL1.E by immediately following a 976 change to TRBLIMITR_EL1.E with at least one ISB instruction before an ERET, or 977 two ISB instructions if no ERET is to take place. 978 979 If unsure, say Y. 980 981config ARM64_ERRATUM_1902691 982 bool "Cortex-A510: 1902691: workaround TRBE trace corruption" 983 depends on CORESIGHT_TRBE 984 default y 985 help 986 This option adds the workaround for ARM Cortex-A510 erratum 1902691. 987 988 Affected Cortex-A510 core might cause trace data corruption, when being written 989 into the memory. Effectively TRBE is broken and hence cannot be used to capture 990 trace data. 991 992 Work around this problem in the driver by just preventing TRBE initialization on 993 affected cpus. The firmware must have disabled the access to TRBE for the kernel 994 on such implementations. This will cover the kernel for any firmware that doesn't 995 do this already. 996 997 If unsure, say Y. 998 999config ARM64_ERRATUM_2457168 1000 bool "Cortex-A510: 2457168: workaround for AMEVCNTR01 incrementing incorrectly" 1001 depends on ARM64_AMU_EXTN 1002 default y 1003 help 1004 This option adds the workaround for ARM Cortex-A510 erratum 2457168. 1005 1006 The AMU counter AMEVCNTR01 (constant counter) should increment at the same rate 1007 as the system counter. On affected Cortex-A510 cores AMEVCNTR01 increments 1008 incorrectly giving a significantly higher output value. 1009 1010 Work around this problem by returning 0 when reading the affected counter in 1011 key locations that results in disabling all users of this counter. This effect 1012 is the same to firmware disabling affected counters. 1013 1014 If unsure, say Y. 1015 1016config ARM64_ERRATUM_2645198 1017 bool "Cortex-A715: 2645198: Workaround possible [ESR|FAR]_ELx corruption" 1018 default y 1019 help 1020 This option adds the workaround for ARM Cortex-A715 erratum 2645198. 1021 1022 If a Cortex-A715 cpu sees a page mapping permissions change from executable 1023 to non-executable, it may corrupt the ESR_ELx and FAR_ELx registers on the 1024 next instruction abort caused by permission fault. 1025 1026 Only user-space does executable to non-executable permission transition via 1027 mprotect() system call. Workaround the problem by doing a break-before-make 1028 TLB invalidation, for all changes to executable user space mappings. 1029 1030 If unsure, say Y. 1031 1032config CAVIUM_ERRATUM_22375 1033 bool "Cavium erratum 22375, 24313" 1034 default y 1035 help 1036 Enable workaround for errata 22375 and 24313. 1037 1038 This implements two gicv3-its errata workarounds for ThunderX. Both 1039 with a small impact affecting only ITS table allocation. 1040 1041 erratum 22375: only alloc 8MB table size 1042 erratum 24313: ignore memory access type 1043 1044 The fixes are in ITS initialization and basically ignore memory access 1045 type and table size provided by the TYPER and BASER registers. 1046 1047 If unsure, say Y. 1048 1049config CAVIUM_ERRATUM_23144 1050 bool "Cavium erratum 23144: ITS SYNC hang on dual socket system" 1051 depends on NUMA 1052 default y 1053 help 1054 ITS SYNC command hang for cross node io and collections/cpu mapping. 1055 1056 If unsure, say Y. 1057 1058config CAVIUM_ERRATUM_23154 1059 bool "Cavium errata 23154 and 38545: GICv3 lacks HW synchronisation" 1060 default y 1061 help 1062 The ThunderX GICv3 implementation requires a modified version for 1063 reading the IAR status to ensure data synchronization 1064 (access to icc_iar1_el1 is not sync'ed before and after). 1065 1066 It also suffers from erratum 38545 (also present on Marvell's 1067 OcteonTX and OcteonTX2), resulting in deactivated interrupts being 1068 spuriously presented to the CPU interface. 1069 1070 If unsure, say Y. 1071 1072config CAVIUM_ERRATUM_27456 1073 bool "Cavium erratum 27456: Broadcast TLBI instructions may cause icache corruption" 1074 default y 1075 help 1076 On ThunderX T88 pass 1.x through 2.1 parts, broadcast TLBI 1077 instructions may cause the icache to become corrupted if it 1078 contains data for a non-current ASID. The fix is to 1079 invalidate the icache when changing the mm context. 1080 1081 If unsure, say Y. 1082 1083config CAVIUM_ERRATUM_30115 1084 bool "Cavium erratum 30115: Guest may disable interrupts in host" 1085 default y 1086 help 1087 On ThunderX T88 pass 1.x through 2.2, T81 pass 1.0 through 1088 1.2, and T83 Pass 1.0, KVM guest execution may disable 1089 interrupts in host. Trapping both GICv3 group-0 and group-1 1090 accesses sidesteps the issue. 1091 1092 If unsure, say Y. 1093 1094config CAVIUM_TX2_ERRATUM_219 1095 bool "Cavium ThunderX2 erratum 219: PRFM between TTBR change and ISB fails" 1096 default y 1097 help 1098 On Cavium ThunderX2, a load, store or prefetch instruction between a 1099 TTBR update and the corresponding context synchronizing operation can 1100 cause a spurious Data Abort to be delivered to any hardware thread in 1101 the CPU core. 1102 1103 Work around the issue by avoiding the problematic code sequence and 1104 trapping KVM guest TTBRx_EL1 writes to EL2 when SMT is enabled. The 1105 trap handler performs the corresponding register access, skips the 1106 instruction and ensures context synchronization by virtue of the 1107 exception return. 1108 1109 If unsure, say Y. 1110 1111config FUJITSU_ERRATUM_010001 1112 bool "Fujitsu-A64FX erratum E#010001: Undefined fault may occur wrongly" 1113 default y 1114 help 1115 This option adds a workaround for Fujitsu-A64FX erratum E#010001. 1116 On some variants of the Fujitsu-A64FX cores ver(1.0, 1.1), memory 1117 accesses may cause undefined fault (Data abort, DFSC=0b111111). 1118 This fault occurs under a specific hardware condition when a 1119 load/store instruction performs an address translation using: 1120 case-1 TTBR0_EL1 with TCR_EL1.NFD0 == 1. 1121 case-2 TTBR0_EL2 with TCR_EL2.NFD0 == 1. 1122 case-3 TTBR1_EL1 with TCR_EL1.NFD1 == 1. 1123 case-4 TTBR1_EL2 with TCR_EL2.NFD1 == 1. 1124 1125 The workaround is to ensure these bits are clear in TCR_ELx. 1126 The workaround only affects the Fujitsu-A64FX. 1127 1128 If unsure, say Y. 1129 1130config HISILICON_ERRATUM_161600802 1131 bool "Hip07 161600802: Erroneous redistributor VLPI base" 1132 default y 1133 help 1134 The HiSilicon Hip07 SoC uses the wrong redistributor base 1135 when issued ITS commands such as VMOVP and VMAPP, and requires 1136 a 128kB offset to be applied to the target address in this commands. 1137 1138 If unsure, say Y. 1139 1140config QCOM_FALKOR_ERRATUM_1003 1141 bool "Falkor E1003: Incorrect translation due to ASID change" 1142 default y 1143 help 1144 On Falkor v1, an incorrect ASID may be cached in the TLB when ASID 1145 and BADDR are changed together in TTBRx_EL1. Since we keep the ASID 1146 in TTBR1_EL1, this situation only occurs in the entry trampoline and 1147 then only for entries in the walk cache, since the leaf translation 1148 is unchanged. Work around the erratum by invalidating the walk cache 1149 entries for the trampoline before entering the kernel proper. 1150 1151config QCOM_FALKOR_ERRATUM_1009 1152 bool "Falkor E1009: Prematurely complete a DSB after a TLBI" 1153 default y 1154 select ARM64_WORKAROUND_REPEAT_TLBI 1155 help 1156 On Falkor v1, the CPU may prematurely complete a DSB following a 1157 TLBI xxIS invalidate maintenance operation. Repeat the TLBI operation 1158 one more time to fix the issue. 1159 1160 If unsure, say Y. 1161 1162config QCOM_QDF2400_ERRATUM_0065 1163 bool "QDF2400 E0065: Incorrect GITS_TYPER.ITT_Entry_size" 1164 default y 1165 help 1166 On Qualcomm Datacenter Technologies QDF2400 SoC, ITS hardware reports 1167 ITE size incorrectly. The GITS_TYPER.ITT_Entry_size field should have 1168 been indicated as 16Bytes (0xf), not 8Bytes (0x7). 1169 1170 If unsure, say Y. 1171 1172config QCOM_FALKOR_ERRATUM_E1041 1173 bool "Falkor E1041: Speculative instruction fetches might cause errant memory access" 1174 default y 1175 help 1176 Falkor CPU may speculatively fetch instructions from an improper 1177 memory location when MMU translation is changed from SCTLR_ELn[M]=1 1178 to SCTLR_ELn[M]=0. Prefix an ISB instruction to fix the problem. 1179 1180 If unsure, say Y. 1181 1182config NVIDIA_CARMEL_CNP_ERRATUM 1183 bool "NVIDIA Carmel CNP: CNP on Carmel semantically different than ARM cores" 1184 default y 1185 help 1186 If CNP is enabled on Carmel cores, non-sharable TLBIs on a core will not 1187 invalidate shared TLB entries installed by a different core, as it would 1188 on standard ARM cores. 1189 1190 If unsure, say Y. 1191 1192config ROCKCHIP_ERRATUM_3588001 1193 bool "Rockchip 3588001: GIC600 can not support shareability attributes" 1194 default y 1195 help 1196 The Rockchip RK3588 GIC600 SoC integration does not support ACE/ACE-lite. 1197 This means, that its sharability feature may not be used, even though it 1198 is supported by the IP itself. 1199 1200 If unsure, say Y. 1201 1202config SOCIONEXT_SYNQUACER_PREITS 1203 bool "Socionext Synquacer: Workaround for GICv3 pre-ITS" 1204 default y 1205 help 1206 Socionext Synquacer SoCs implement a separate h/w block to generate 1207 MSI doorbell writes with non-zero values for the device ID. 1208 1209 If unsure, say Y. 1210 1211endmenu # "ARM errata workarounds via the alternatives framework" 1212 1213choice 1214 prompt "Page size" 1215 default ARM64_4K_PAGES 1216 help 1217 Page size (translation granule) configuration. 1218 1219config ARM64_4K_PAGES 1220 bool "4KB" 1221 help 1222 This feature enables 4KB pages support. 1223 1224config ARM64_16K_PAGES 1225 bool "16KB" 1226 help 1227 The system will use 16KB pages support. AArch32 emulation 1228 requires applications compiled with 16K (or a multiple of 16K) 1229 aligned segments. 1230 1231config ARM64_64K_PAGES 1232 bool "64KB" 1233 help 1234 This feature enables 64KB pages support (4KB by default) 1235 allowing only two levels of page tables and faster TLB 1236 look-up. AArch32 emulation requires applications compiled 1237 with 64K aligned segments. 1238 1239endchoice 1240 1241choice 1242 prompt "Virtual address space size" 1243 default ARM64_VA_BITS_39 if ARM64_4K_PAGES 1244 default ARM64_VA_BITS_47 if ARM64_16K_PAGES 1245 default ARM64_VA_BITS_42 if ARM64_64K_PAGES 1246 help 1247 Allows choosing one of multiple possible virtual address 1248 space sizes. The level of translation table is determined by 1249 a combination of page size and virtual address space size. 1250 1251config ARM64_VA_BITS_36 1252 bool "36-bit" if EXPERT 1253 depends on ARM64_16K_PAGES 1254 1255config ARM64_VA_BITS_39 1256 bool "39-bit" 1257 depends on ARM64_4K_PAGES 1258 1259config ARM64_VA_BITS_42 1260 bool "42-bit" 1261 depends on ARM64_64K_PAGES 1262 1263config ARM64_VA_BITS_47 1264 bool "47-bit" 1265 depends on ARM64_16K_PAGES 1266 1267config ARM64_VA_BITS_48 1268 bool "48-bit" 1269 1270config ARM64_VA_BITS_52 1271 bool "52-bit" 1272 depends on ARM64_64K_PAGES && (ARM64_PAN || !ARM64_SW_TTBR0_PAN) 1273 help 1274 Enable 52-bit virtual addressing for userspace when explicitly 1275 requested via a hint to mmap(). The kernel will also use 52-bit 1276 virtual addresses for its own mappings (provided HW support for 1277 this feature is available, otherwise it reverts to 48-bit). 1278 1279 NOTE: Enabling 52-bit virtual addressing in conjunction with 1280 ARMv8.3 Pointer Authentication will result in the PAC being 1281 reduced from 7 bits to 3 bits, which may have a significant 1282 impact on its susceptibility to brute-force attacks. 1283 1284 If unsure, select 48-bit virtual addressing instead. 1285 1286endchoice 1287 1288config ARM64_FORCE_52BIT 1289 bool "Force 52-bit virtual addresses for userspace" 1290 depends on ARM64_VA_BITS_52 && EXPERT 1291 help 1292 For systems with 52-bit userspace VAs enabled, the kernel will attempt 1293 to maintain compatibility with older software by providing 48-bit VAs 1294 unless a hint is supplied to mmap. 1295 1296 This configuration option disables the 48-bit compatibility logic, and 1297 forces all userspace addresses to be 52-bit on HW that supports it. One 1298 should only enable this configuration option for stress testing userspace 1299 memory management code. If unsure say N here. 1300 1301config ARM64_VA_BITS 1302 int 1303 default 36 if ARM64_VA_BITS_36 1304 default 39 if ARM64_VA_BITS_39 1305 default 42 if ARM64_VA_BITS_42 1306 default 47 if ARM64_VA_BITS_47 1307 default 48 if ARM64_VA_BITS_48 1308 default 52 if ARM64_VA_BITS_52 1309 1310choice 1311 prompt "Physical address space size" 1312 default ARM64_PA_BITS_48 1313 help 1314 Choose the maximum physical address range that the kernel will 1315 support. 1316 1317config ARM64_PA_BITS_48 1318 bool "48-bit" 1319 1320config ARM64_PA_BITS_52 1321 bool "52-bit (ARMv8.2)" 1322 depends on ARM64_64K_PAGES 1323 depends on ARM64_PAN || !ARM64_SW_TTBR0_PAN 1324 help 1325 Enable support for a 52-bit physical address space, introduced as 1326 part of the ARMv8.2-LPA extension. 1327 1328 With this enabled, the kernel will also continue to work on CPUs that 1329 do not support ARMv8.2-LPA, but with some added memory overhead (and 1330 minor performance overhead). 1331 1332endchoice 1333 1334config ARM64_PA_BITS 1335 int 1336 default 48 if ARM64_PA_BITS_48 1337 default 52 if ARM64_PA_BITS_52 1338 1339choice 1340 prompt "Endianness" 1341 default CPU_LITTLE_ENDIAN 1342 help 1343 Select the endianness of data accesses performed by the CPU. Userspace 1344 applications will need to be compiled and linked for the endianness 1345 that is selected here. 1346 1347config CPU_BIG_ENDIAN 1348 bool "Build big-endian kernel" 1349 depends on !LD_IS_LLD || LLD_VERSION >= 130000 1350 help 1351 Say Y if you plan on running a kernel with a big-endian userspace. 1352 1353config CPU_LITTLE_ENDIAN 1354 bool "Build little-endian kernel" 1355 help 1356 Say Y if you plan on running a kernel with a little-endian userspace. 1357 This is usually the case for distributions targeting arm64. 1358 1359endchoice 1360 1361config SCHED_MC 1362 bool "Multi-core scheduler support" 1363 help 1364 Multi-core scheduler support improves the CPU scheduler's decision 1365 making when dealing with multi-core CPU chips at a cost of slightly 1366 increased overhead in some places. If unsure say N here. 1367 1368config SCHED_CLUSTER 1369 bool "Cluster scheduler support" 1370 help 1371 Cluster scheduler support improves the CPU scheduler's decision 1372 making when dealing with machines that have clusters of CPUs. 1373 Cluster usually means a couple of CPUs which are placed closely 1374 by sharing mid-level caches, last-level cache tags or internal 1375 busses. 1376 1377config SCHED_SMT 1378 bool "SMT scheduler support" 1379 help 1380 Improves the CPU scheduler's decision making when dealing with 1381 MultiThreading at a cost of slightly increased overhead in some 1382 places. If unsure say N here. 1383 1384config NR_CPUS 1385 int "Maximum number of CPUs (2-4096)" 1386 range 2 4096 1387 default "256" 1388 1389config HOTPLUG_CPU 1390 bool "Support for hot-pluggable CPUs" 1391 select GENERIC_IRQ_MIGRATION 1392 help 1393 Say Y here to experiment with turning CPUs off and on. CPUs 1394 can be controlled through /sys/devices/system/cpu. 1395 1396# Common NUMA Features 1397config NUMA 1398 bool "NUMA Memory Allocation and Scheduler Support" 1399 select GENERIC_ARCH_NUMA 1400 select ACPI_NUMA if ACPI 1401 select OF_NUMA 1402 select HAVE_SETUP_PER_CPU_AREA 1403 select NEED_PER_CPU_EMBED_FIRST_CHUNK 1404 select NEED_PER_CPU_PAGE_FIRST_CHUNK 1405 select USE_PERCPU_NUMA_NODE_ID 1406 help 1407 Enable NUMA (Non-Uniform Memory Access) support. 1408 1409 The kernel will try to allocate memory used by a CPU on the 1410 local memory of the CPU and add some more 1411 NUMA awareness to the kernel. 1412 1413config NODES_SHIFT 1414 int "Maximum NUMA Nodes (as a power of 2)" 1415 range 1 10 1416 default "4" 1417 depends on NUMA 1418 help 1419 Specify the maximum number of NUMA Nodes available on the target 1420 system. Increases memory reserved to accommodate various tables. 1421 1422source "kernel/Kconfig.hz" 1423 1424config ARCH_SPARSEMEM_ENABLE 1425 def_bool y 1426 select SPARSEMEM_VMEMMAP_ENABLE 1427 select SPARSEMEM_VMEMMAP 1428 1429config HW_PERF_EVENTS 1430 def_bool y 1431 depends on ARM_PMU 1432 1433# Supported by clang >= 7.0 or GCC >= 12.0.0 1434config CC_HAVE_SHADOW_CALL_STACK 1435 def_bool $(cc-option, -fsanitize=shadow-call-stack -ffixed-x18) 1436 1437config PARAVIRT 1438 bool "Enable paravirtualization code" 1439 help 1440 This changes the kernel so it can modify itself when it is run 1441 under a hypervisor, potentially improving performance significantly 1442 over full virtualization. 1443 1444config PARAVIRT_TIME_ACCOUNTING 1445 bool "Paravirtual steal time accounting" 1446 select PARAVIRT 1447 help 1448 Select this option to enable fine granularity task steal time 1449 accounting. Time spent executing other tasks in parallel with 1450 the current vCPU is discounted from the vCPU power. To account for 1451 that, there can be a small performance impact. 1452 1453 If in doubt, say N here. 1454 1455config KEXEC 1456 depends on PM_SLEEP_SMP 1457 select KEXEC_CORE 1458 bool "kexec system call" 1459 help 1460 kexec is a system call that implements the ability to shutdown your 1461 current kernel, and to start another kernel. It is like a reboot 1462 but it is independent of the system firmware. And like a reboot 1463 you can start any kernel with it, not just Linux. 1464 1465config KEXEC_FILE 1466 bool "kexec file based system call" 1467 select KEXEC_CORE 1468 select HAVE_IMA_KEXEC if IMA 1469 help 1470 This is new version of kexec system call. This system call is 1471 file based and takes file descriptors as system call argument 1472 for kernel and initramfs as opposed to list of segments as 1473 accepted by previous system call. 1474 1475config KEXEC_SIG 1476 bool "Verify kernel signature during kexec_file_load() syscall" 1477 depends on KEXEC_FILE 1478 help 1479 Select this option to verify a signature with loaded kernel 1480 image. If configured, any attempt of loading a image without 1481 valid signature will fail. 1482 1483 In addition to that option, you need to enable signature 1484 verification for the corresponding kernel image type being 1485 loaded in order for this to work. 1486 1487config KEXEC_IMAGE_VERIFY_SIG 1488 bool "Enable Image signature verification support" 1489 default y 1490 depends on KEXEC_SIG 1491 depends on EFI && SIGNED_PE_FILE_VERIFICATION 1492 help 1493 Enable Image signature verification support. 1494 1495comment "Support for PE file signature verification disabled" 1496 depends on KEXEC_SIG 1497 depends on !EFI || !SIGNED_PE_FILE_VERIFICATION 1498 1499config CRASH_DUMP 1500 bool "Build kdump crash kernel" 1501 help 1502 Generate crash dump after being started by kexec. This should 1503 be normally only set in special crash dump kernels which are 1504 loaded in the main kernel with kexec-tools into a specially 1505 reserved region and then later executed after a crash by 1506 kdump/kexec. 1507 1508 For more details see Documentation/admin-guide/kdump/kdump.rst 1509 1510config TRANS_TABLE 1511 def_bool y 1512 depends on HIBERNATION || KEXEC_CORE 1513 1514config XEN_DOM0 1515 def_bool y 1516 depends on XEN 1517 1518config XEN 1519 bool "Xen guest support on ARM64" 1520 depends on ARM64 && OF 1521 select SWIOTLB_XEN 1522 select PARAVIRT 1523 help 1524 Say Y if you want to run Linux in a Virtual Machine on Xen on ARM64. 1525 1526# include/linux/mmzone.h requires the following to be true: 1527# 1528# MAX_ORDER + PAGE_SHIFT <= SECTION_SIZE_BITS 1529# 1530# so the maximum value of MAX_ORDER is SECTION_SIZE_BITS - PAGE_SHIFT: 1531# 1532# | SECTION_SIZE_BITS | PAGE_SHIFT | max MAX_ORDER | default MAX_ORDER | 1533# ----+-------------------+--------------+-----------------+--------------------+ 1534# 4K | 27 | 12 | 15 | 10 | 1535# 16K | 27 | 14 | 13 | 11 | 1536# 64K | 29 | 16 | 13 | 13 | 1537config ARCH_FORCE_MAX_ORDER 1538 int "Order of maximal physically contiguous allocations" if EXPERT && (ARM64_4K_PAGES || ARM64_16K_PAGES) 1539 default "13" if ARM64_64K_PAGES 1540 default "11" if ARM64_16K_PAGES 1541 default "10" 1542 help 1543 The kernel page allocator limits the size of maximal physically 1544 contiguous allocations. The limit is called MAX_ORDER and it 1545 defines the maximal power of two of number of pages that can be 1546 allocated as a single contiguous block. This option allows 1547 overriding the default setting when ability to allocate very 1548 large blocks of physically contiguous memory is required. 1549 1550 The maximal size of allocation cannot exceed the size of the 1551 section, so the value of MAX_ORDER should satisfy 1552 1553 MAX_ORDER + PAGE_SHIFT <= SECTION_SIZE_BITS 1554 1555 Don't change if unsure. 1556 1557config UNMAP_KERNEL_AT_EL0 1558 bool "Unmap kernel when running in userspace (aka \"KAISER\")" if EXPERT 1559 default y 1560 help 1561 Speculation attacks against some high-performance processors can 1562 be used to bypass MMU permission checks and leak kernel data to 1563 userspace. This can be defended against by unmapping the kernel 1564 when running in userspace, mapping it back in on exception entry 1565 via a trampoline page in the vector table. 1566 1567 If unsure, say Y. 1568 1569config MITIGATE_SPECTRE_BRANCH_HISTORY 1570 bool "Mitigate Spectre style attacks against branch history" if EXPERT 1571 default y 1572 help 1573 Speculation attacks against some high-performance processors can 1574 make use of branch history to influence future speculation. 1575 When taking an exception from user-space, a sequence of branches 1576 or a firmware call overwrites the branch history. 1577 1578config RODATA_FULL_DEFAULT_ENABLED 1579 bool "Apply r/o permissions of VM areas also to their linear aliases" 1580 default y 1581 help 1582 Apply read-only attributes of VM areas to the linear alias of 1583 the backing pages as well. This prevents code or read-only data 1584 from being modified (inadvertently or intentionally) via another 1585 mapping of the same memory page. This additional enhancement can 1586 be turned off at runtime by passing rodata=[off|on] (and turned on 1587 with rodata=full if this option is set to 'n') 1588 1589 This requires the linear region to be mapped down to pages, 1590 which may adversely affect performance in some cases. 1591 1592config ARM64_SW_TTBR0_PAN 1593 bool "Emulate Privileged Access Never using TTBR0_EL1 switching" 1594 help 1595 Enabling this option prevents the kernel from accessing 1596 user-space memory directly by pointing TTBR0_EL1 to a reserved 1597 zeroed area and reserved ASID. The user access routines 1598 restore the valid TTBR0_EL1 temporarily. 1599 1600config ARM64_TAGGED_ADDR_ABI 1601 bool "Enable the tagged user addresses syscall ABI" 1602 default y 1603 help 1604 When this option is enabled, user applications can opt in to a 1605 relaxed ABI via prctl() allowing tagged addresses to be passed 1606 to system calls as pointer arguments. For details, see 1607 Documentation/arm64/tagged-address-abi.rst. 1608 1609menuconfig COMPAT 1610 bool "Kernel support for 32-bit EL0" 1611 depends on ARM64_4K_PAGES || EXPERT 1612 select HAVE_UID16 1613 select OLD_SIGSUSPEND3 1614 select COMPAT_OLD_SIGACTION 1615 help 1616 This option enables support for a 32-bit EL0 running under a 64-bit 1617 kernel at EL1. AArch32-specific components such as system calls, 1618 the user helper functions, VFP support and the ptrace interface are 1619 handled appropriately by the kernel. 1620 1621 If you use a page size other than 4KB (i.e, 16KB or 64KB), please be aware 1622 that you will only be able to execute AArch32 binaries that were compiled 1623 with page size aligned segments. 1624 1625 If you want to execute 32-bit userspace applications, say Y. 1626 1627if COMPAT 1628 1629config KUSER_HELPERS 1630 bool "Enable kuser helpers page for 32-bit applications" 1631 default y 1632 help 1633 Warning: disabling this option may break 32-bit user programs. 1634 1635 Provide kuser helpers to compat tasks. The kernel provides 1636 helper code to userspace in read only form at a fixed location 1637 to allow userspace to be independent of the CPU type fitted to 1638 the system. This permits binaries to be run on ARMv4 through 1639 to ARMv8 without modification. 1640 1641 See Documentation/arm/kernel_user_helpers.rst for details. 1642 1643 However, the fixed address nature of these helpers can be used 1644 by ROP (return orientated programming) authors when creating 1645 exploits. 1646 1647 If all of the binaries and libraries which run on your platform 1648 are built specifically for your platform, and make no use of 1649 these helpers, then you can turn this option off to hinder 1650 such exploits. However, in that case, if a binary or library 1651 relying on those helpers is run, it will not function correctly. 1652 1653 Say N here only if you are absolutely certain that you do not 1654 need these helpers; otherwise, the safe option is to say Y. 1655 1656config COMPAT_VDSO 1657 bool "Enable vDSO for 32-bit applications" 1658 depends on !CPU_BIG_ENDIAN 1659 depends on (CC_IS_CLANG && LD_IS_LLD) || "$(CROSS_COMPILE_COMPAT)" != "" 1660 select GENERIC_COMPAT_VDSO 1661 default y 1662 help 1663 Place in the process address space of 32-bit applications an 1664 ELF shared object providing fast implementations of gettimeofday 1665 and clock_gettime. 1666 1667 You must have a 32-bit build of glibc 2.22 or later for programs 1668 to seamlessly take advantage of this. 1669 1670config THUMB2_COMPAT_VDSO 1671 bool "Compile the 32-bit vDSO for Thumb-2 mode" if EXPERT 1672 depends on COMPAT_VDSO 1673 default y 1674 help 1675 Compile the compat vDSO with '-mthumb -fomit-frame-pointer' if y, 1676 otherwise with '-marm'. 1677 1678config COMPAT_ALIGNMENT_FIXUPS 1679 bool "Fix up misaligned multi-word loads and stores in user space" 1680 1681menuconfig ARMV8_DEPRECATED 1682 bool "Emulate deprecated/obsolete ARMv8 instructions" 1683 depends on SYSCTL 1684 help 1685 Legacy software support may require certain instructions 1686 that have been deprecated or obsoleted in the architecture. 1687 1688 Enable this config to enable selective emulation of these 1689 features. 1690 1691 If unsure, say Y 1692 1693if ARMV8_DEPRECATED 1694 1695config SWP_EMULATION 1696 bool "Emulate SWP/SWPB instructions" 1697 help 1698 ARMv8 obsoletes the use of A32 SWP/SWPB instructions such that 1699 they are always undefined. Say Y here to enable software 1700 emulation of these instructions for userspace using LDXR/STXR. 1701 This feature can be controlled at runtime with the abi.swp 1702 sysctl which is disabled by default. 1703 1704 In some older versions of glibc [<=2.8] SWP is used during futex 1705 trylock() operations with the assumption that the code will not 1706 be preempted. This invalid assumption may be more likely to fail 1707 with SWP emulation enabled, leading to deadlock of the user 1708 application. 1709 1710 NOTE: when accessing uncached shared regions, LDXR/STXR rely 1711 on an external transaction monitoring block called a global 1712 monitor to maintain update atomicity. If your system does not 1713 implement a global monitor, this option can cause programs that 1714 perform SWP operations to uncached memory to deadlock. 1715 1716 If unsure, say Y 1717 1718config CP15_BARRIER_EMULATION 1719 bool "Emulate CP15 Barrier instructions" 1720 help 1721 The CP15 barrier instructions - CP15ISB, CP15DSB, and 1722 CP15DMB - are deprecated in ARMv8 (and ARMv7). It is 1723 strongly recommended to use the ISB, DSB, and DMB 1724 instructions instead. 1725 1726 Say Y here to enable software emulation of these 1727 instructions for AArch32 userspace code. When this option is 1728 enabled, CP15 barrier usage is traced which can help 1729 identify software that needs updating. This feature can be 1730 controlled at runtime with the abi.cp15_barrier sysctl. 1731 1732 If unsure, say Y 1733 1734config SETEND_EMULATION 1735 bool "Emulate SETEND instruction" 1736 help 1737 The SETEND instruction alters the data-endianness of the 1738 AArch32 EL0, and is deprecated in ARMv8. 1739 1740 Say Y here to enable software emulation of the instruction 1741 for AArch32 userspace code. This feature can be controlled 1742 at runtime with the abi.setend sysctl. 1743 1744 Note: All the cpus on the system must have mixed endian support at EL0 1745 for this feature to be enabled. If a new CPU - which doesn't support mixed 1746 endian - is hotplugged in after this feature has been enabled, there could 1747 be unexpected results in the applications. 1748 1749 If unsure, say Y 1750endif # ARMV8_DEPRECATED 1751 1752endif # COMPAT 1753 1754menu "ARMv8.1 architectural features" 1755 1756config ARM64_HW_AFDBM 1757 bool "Support for hardware updates of the Access and Dirty page flags" 1758 default y 1759 help 1760 The ARMv8.1 architecture extensions introduce support for 1761 hardware updates of the access and dirty information in page 1762 table entries. When enabled in TCR_EL1 (HA and HD bits) on 1763 capable processors, accesses to pages with PTE_AF cleared will 1764 set this bit instead of raising an access flag fault. 1765 Similarly, writes to read-only pages with the DBM bit set will 1766 clear the read-only bit (AP[2]) instead of raising a 1767 permission fault. 1768 1769 Kernels built with this configuration option enabled continue 1770 to work on pre-ARMv8.1 hardware and the performance impact is 1771 minimal. If unsure, say Y. 1772 1773config ARM64_PAN 1774 bool "Enable support for Privileged Access Never (PAN)" 1775 default y 1776 help 1777 Privileged Access Never (PAN; part of the ARMv8.1 Extensions) 1778 prevents the kernel or hypervisor from accessing user-space (EL0) 1779 memory directly. 1780 1781 Choosing this option will cause any unprotected (not using 1782 copy_to_user et al) memory access to fail with a permission fault. 1783 1784 The feature is detected at runtime, and will remain as a 'nop' 1785 instruction if the cpu does not implement the feature. 1786 1787config AS_HAS_LDAPR 1788 def_bool $(as-instr,.arch_extension rcpc) 1789 1790config AS_HAS_LSE_ATOMICS 1791 def_bool $(as-instr,.arch_extension lse) 1792 1793config ARM64_LSE_ATOMICS 1794 bool 1795 default ARM64_USE_LSE_ATOMICS 1796 depends on AS_HAS_LSE_ATOMICS 1797 1798config ARM64_USE_LSE_ATOMICS 1799 bool "Atomic instructions" 1800 default y 1801 help 1802 As part of the Large System Extensions, ARMv8.1 introduces new 1803 atomic instructions that are designed specifically to scale in 1804 very large systems. 1805 1806 Say Y here to make use of these instructions for the in-kernel 1807 atomic routines. This incurs a small overhead on CPUs that do 1808 not support these instructions and requires the kernel to be 1809 built with binutils >= 2.25 in order for the new instructions 1810 to be used. 1811 1812endmenu # "ARMv8.1 architectural features" 1813 1814menu "ARMv8.2 architectural features" 1815 1816config AS_HAS_ARMV8_2 1817 def_bool $(cc-option,-Wa$(comma)-march=armv8.2-a) 1818 1819config AS_HAS_SHA3 1820 def_bool $(as-instr,.arch armv8.2-a+sha3) 1821 1822config ARM64_PMEM 1823 bool "Enable support for persistent memory" 1824 select ARCH_HAS_PMEM_API 1825 select ARCH_HAS_UACCESS_FLUSHCACHE 1826 help 1827 Say Y to enable support for the persistent memory API based on the 1828 ARMv8.2 DCPoP feature. 1829 1830 The feature is detected at runtime, and the kernel will use DC CVAC 1831 operations if DC CVAP is not supported (following the behaviour of 1832 DC CVAP itself if the system does not define a point of persistence). 1833 1834config ARM64_RAS_EXTN 1835 bool "Enable support for RAS CPU Extensions" 1836 default y 1837 help 1838 CPUs that support the Reliability, Availability and Serviceability 1839 (RAS) Extensions, part of ARMv8.2 are able to track faults and 1840 errors, classify them and report them to software. 1841 1842 On CPUs with these extensions system software can use additional 1843 barriers to determine if faults are pending and read the 1844 classification from a new set of registers. 1845 1846 Selecting this feature will allow the kernel to use these barriers 1847 and access the new registers if the system supports the extension. 1848 Platform RAS features may additionally depend on firmware support. 1849 1850config ARM64_CNP 1851 bool "Enable support for Common Not Private (CNP) translations" 1852 default y 1853 depends on ARM64_PAN || !ARM64_SW_TTBR0_PAN 1854 help 1855 Common Not Private (CNP) allows translation table entries to 1856 be shared between different PEs in the same inner shareable 1857 domain, so the hardware can use this fact to optimise the 1858 caching of such entries in the TLB. 1859 1860 Selecting this option allows the CNP feature to be detected 1861 at runtime, and does not affect PEs that do not implement 1862 this feature. 1863 1864endmenu # "ARMv8.2 architectural features" 1865 1866menu "ARMv8.3 architectural features" 1867 1868config ARM64_PTR_AUTH 1869 bool "Enable support for pointer authentication" 1870 default y 1871 help 1872 Pointer authentication (part of the ARMv8.3 Extensions) provides 1873 instructions for signing and authenticating pointers against secret 1874 keys, which can be used to mitigate Return Oriented Programming (ROP) 1875 and other attacks. 1876 1877 This option enables these instructions at EL0 (i.e. for userspace). 1878 Choosing this option will cause the kernel to initialise secret keys 1879 for each process at exec() time, with these keys being 1880 context-switched along with the process. 1881 1882 The feature is detected at runtime. If the feature is not present in 1883 hardware it will not be advertised to userspace/KVM guest nor will it 1884 be enabled. 1885 1886 If the feature is present on the boot CPU but not on a late CPU, then 1887 the late CPU will be parked. Also, if the boot CPU does not have 1888 address auth and the late CPU has then the late CPU will still boot 1889 but with the feature disabled. On such a system, this option should 1890 not be selected. 1891 1892config ARM64_PTR_AUTH_KERNEL 1893 bool "Use pointer authentication for kernel" 1894 default y 1895 depends on ARM64_PTR_AUTH 1896 depends on (CC_HAS_SIGN_RETURN_ADDRESS || CC_HAS_BRANCH_PROT_PAC_RET) && AS_HAS_ARMV8_3 1897 # Modern compilers insert a .note.gnu.property section note for PAC 1898 # which is only understood by binutils starting with version 2.33.1. 1899 depends on LD_IS_LLD || LD_VERSION >= 23301 || (CC_IS_GCC && GCC_VERSION < 90100) 1900 depends on !CC_IS_CLANG || AS_HAS_CFI_NEGATE_RA_STATE 1901 depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_ARGS) 1902 help 1903 If the compiler supports the -mbranch-protection or 1904 -msign-return-address flag (e.g. GCC 7 or later), then this option 1905 will cause the kernel itself to be compiled with return address 1906 protection. In this case, and if the target hardware is known to 1907 support pointer authentication, then CONFIG_STACKPROTECTOR can be 1908 disabled with minimal loss of protection. 1909 1910 This feature works with FUNCTION_GRAPH_TRACER option only if 1911 DYNAMIC_FTRACE_WITH_ARGS is enabled. 1912 1913config CC_HAS_BRANCH_PROT_PAC_RET 1914 # GCC 9 or later, clang 8 or later 1915 def_bool $(cc-option,-mbranch-protection=pac-ret+leaf) 1916 1917config CC_HAS_SIGN_RETURN_ADDRESS 1918 # GCC 7, 8 1919 def_bool $(cc-option,-msign-return-address=all) 1920 1921config AS_HAS_ARMV8_3 1922 def_bool $(cc-option,-Wa$(comma)-march=armv8.3-a) 1923 1924config AS_HAS_CFI_NEGATE_RA_STATE 1925 def_bool $(as-instr,.cfi_startproc\n.cfi_negate_ra_state\n.cfi_endproc\n) 1926 1927endmenu # "ARMv8.3 architectural features" 1928 1929menu "ARMv8.4 architectural features" 1930 1931config ARM64_AMU_EXTN 1932 bool "Enable support for the Activity Monitors Unit CPU extension" 1933 default y 1934 help 1935 The activity monitors extension is an optional extension introduced 1936 by the ARMv8.4 CPU architecture. This enables support for version 1 1937 of the activity monitors architecture, AMUv1. 1938 1939 To enable the use of this extension on CPUs that implement it, say Y. 1940 1941 Note that for architectural reasons, firmware _must_ implement AMU 1942 support when running on CPUs that present the activity monitors 1943 extension. The required support is present in: 1944 * Version 1.5 and later of the ARM Trusted Firmware 1945 1946 For kernels that have this configuration enabled but boot with broken 1947 firmware, you may need to say N here until the firmware is fixed. 1948 Otherwise you may experience firmware panics or lockups when 1949 accessing the counter registers. Even if you are not observing these 1950 symptoms, the values returned by the register reads might not 1951 correctly reflect reality. Most commonly, the value read will be 0, 1952 indicating that the counter is not enabled. 1953 1954config AS_HAS_ARMV8_4 1955 def_bool $(cc-option,-Wa$(comma)-march=armv8.4-a) 1956 1957config ARM64_TLB_RANGE 1958 bool "Enable support for tlbi range feature" 1959 default y 1960 depends on AS_HAS_ARMV8_4 1961 help 1962 ARMv8.4-TLBI provides TLBI invalidation instruction that apply to a 1963 range of input addresses. 1964 1965 The feature introduces new assembly instructions, and they were 1966 support when binutils >= 2.30. 1967 1968endmenu # "ARMv8.4 architectural features" 1969 1970menu "ARMv8.5 architectural features" 1971 1972config AS_HAS_ARMV8_5 1973 def_bool $(cc-option,-Wa$(comma)-march=armv8.5-a) 1974 1975config ARM64_BTI 1976 bool "Branch Target Identification support" 1977 default y 1978 help 1979 Branch Target Identification (part of the ARMv8.5 Extensions) 1980 provides a mechanism to limit the set of locations to which computed 1981 branch instructions such as BR or BLR can jump. 1982 1983 To make use of BTI on CPUs that support it, say Y. 1984 1985 BTI is intended to provide complementary protection to other control 1986 flow integrity protection mechanisms, such as the Pointer 1987 authentication mechanism provided as part of the ARMv8.3 Extensions. 1988 For this reason, it does not make sense to enable this option without 1989 also enabling support for pointer authentication. Thus, when 1990 enabling this option you should also select ARM64_PTR_AUTH=y. 1991 1992 Userspace binaries must also be specifically compiled to make use of 1993 this mechanism. If you say N here or the hardware does not support 1994 BTI, such binaries can still run, but you get no additional 1995 enforcement of branch destinations. 1996 1997config ARM64_BTI_KERNEL 1998 bool "Use Branch Target Identification for kernel" 1999 default y 2000 depends on ARM64_BTI 2001 depends on ARM64_PTR_AUTH_KERNEL 2002 depends on CC_HAS_BRANCH_PROT_PAC_RET_BTI 2003 # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=94697 2004 depends on !CC_IS_GCC || GCC_VERSION >= 100100 2005 # https://gcc.gnu.org/bugzilla/show_bug.cgi?id=106671 2006 depends on !CC_IS_GCC 2007 # https://github.com/llvm/llvm-project/commit/a88c722e687e6780dcd6a58718350dc76fcc4cc9 2008 depends on !CC_IS_CLANG || CLANG_VERSION >= 120000 2009 depends on (!FUNCTION_GRAPH_TRACER || DYNAMIC_FTRACE_WITH_ARGS) 2010 help 2011 Build the kernel with Branch Target Identification annotations 2012 and enable enforcement of this for kernel code. When this option 2013 is enabled and the system supports BTI all kernel code including 2014 modular code must have BTI enabled. 2015 2016config CC_HAS_BRANCH_PROT_PAC_RET_BTI 2017 # GCC 9 or later, clang 8 or later 2018 def_bool $(cc-option,-mbranch-protection=pac-ret+leaf+bti) 2019 2020config ARM64_E0PD 2021 bool "Enable support for E0PD" 2022 default y 2023 help 2024 E0PD (part of the ARMv8.5 extensions) allows us to ensure 2025 that EL0 accesses made via TTBR1 always fault in constant time, 2026 providing similar benefits to KASLR as those provided by KPTI, but 2027 with lower overhead and without disrupting legitimate access to 2028 kernel memory such as SPE. 2029 2030 This option enables E0PD for TTBR1 where available. 2031 2032config ARM64_AS_HAS_MTE 2033 # Initial support for MTE went in binutils 2.32.0, checked with 2034 # ".arch armv8.5-a+memtag" below. However, this was incomplete 2035 # as a late addition to the final architecture spec (LDGM/STGM) 2036 # is only supported in the newer 2.32.x and 2.33 binutils 2037 # versions, hence the extra "stgm" instruction check below. 2038 def_bool $(as-instr,.arch armv8.5-a+memtag\nstgm xzr$(comma)[x0]) 2039 2040config ARM64_MTE 2041 bool "Memory Tagging Extension support" 2042 default y 2043 depends on ARM64_AS_HAS_MTE && ARM64_TAGGED_ADDR_ABI 2044 depends on AS_HAS_ARMV8_5 2045 depends on AS_HAS_LSE_ATOMICS 2046 # Required for tag checking in the uaccess routines 2047 depends on ARM64_PAN 2048 select ARCH_HAS_SUBPAGE_FAULTS 2049 select ARCH_USES_HIGH_VMA_FLAGS 2050 select ARCH_USES_PG_ARCH_X 2051 help 2052 Memory Tagging (part of the ARMv8.5 Extensions) provides 2053 architectural support for run-time, always-on detection of 2054 various classes of memory error to aid with software debugging 2055 to eliminate vulnerabilities arising from memory-unsafe 2056 languages. 2057 2058 This option enables the support for the Memory Tagging 2059 Extension at EL0 (i.e. for userspace). 2060 2061 Selecting this option allows the feature to be detected at 2062 runtime. Any secondary CPU not implementing this feature will 2063 not be allowed a late bring-up. 2064 2065 Userspace binaries that want to use this feature must 2066 explicitly opt in. The mechanism for the userspace is 2067 described in: 2068 2069 Documentation/arm64/memory-tagging-extension.rst. 2070 2071endmenu # "ARMv8.5 architectural features" 2072 2073menu "ARMv8.7 architectural features" 2074 2075config ARM64_EPAN 2076 bool "Enable support for Enhanced Privileged Access Never (EPAN)" 2077 default y 2078 depends on ARM64_PAN 2079 help 2080 Enhanced Privileged Access Never (EPAN) allows Privileged 2081 Access Never to be used with Execute-only mappings. 2082 2083 The feature is detected at runtime, and will remain disabled 2084 if the cpu does not implement the feature. 2085endmenu # "ARMv8.7 architectural features" 2086 2087config ARM64_SVE 2088 bool "ARM Scalable Vector Extension support" 2089 default y 2090 help 2091 The Scalable Vector Extension (SVE) is an extension to the AArch64 2092 execution state which complements and extends the SIMD functionality 2093 of the base architecture to support much larger vectors and to enable 2094 additional vectorisation opportunities. 2095 2096 To enable use of this extension on CPUs that implement it, say Y. 2097 2098 On CPUs that support the SVE2 extensions, this option will enable 2099 those too. 2100 2101 Note that for architectural reasons, firmware _must_ implement SVE 2102 support when running on SVE capable hardware. The required support 2103 is present in: 2104 2105 * version 1.5 and later of the ARM Trusted Firmware 2106 * the AArch64 boot wrapper since commit 5e1261e08abf 2107 ("bootwrapper: SVE: Enable SVE for EL2 and below"). 2108 2109 For other firmware implementations, consult the firmware documentation 2110 or vendor. 2111 2112 If you need the kernel to boot on SVE-capable hardware with broken 2113 firmware, you may need to say N here until you get your firmware 2114 fixed. Otherwise, you may experience firmware panics or lockups when 2115 booting the kernel. If unsure and you are not observing these 2116 symptoms, you should assume that it is safe to say Y. 2117 2118config ARM64_SME 2119 bool "ARM Scalable Matrix Extension support" 2120 default y 2121 depends on ARM64_SVE 2122 help 2123 The Scalable Matrix Extension (SME) is an extension to the AArch64 2124 execution state which utilises a substantial subset of the SVE 2125 instruction set, together with the addition of new architectural 2126 register state capable of holding two dimensional matrix tiles to 2127 enable various matrix operations. 2128 2129config ARM64_MODULE_PLTS 2130 bool "Use PLTs to allow module memory to spill over into vmalloc area" 2131 depends on MODULES 2132 select HAVE_MOD_ARCH_SPECIFIC 2133 help 2134 Allocate PLTs when loading modules so that jumps and calls whose 2135 targets are too far away for their relative offsets to be encoded 2136 in the instructions themselves can be bounced via veneers in the 2137 module's PLT. This allows modules to be allocated in the generic 2138 vmalloc area after the dedicated module memory area has been 2139 exhausted. 2140 2141 When running with address space randomization (KASLR), the module 2142 region itself may be too far away for ordinary relative jumps and 2143 calls, and so in that case, module PLTs are required and cannot be 2144 disabled. 2145 2146 Specific errata workaround(s) might also force module PLTs to be 2147 enabled (ARM64_ERRATUM_843419). 2148 2149config ARM64_PSEUDO_NMI 2150 bool "Support for NMI-like interrupts" 2151 select ARM_GIC_V3 2152 help 2153 Adds support for mimicking Non-Maskable Interrupts through the use of 2154 GIC interrupt priority. This support requires version 3 or later of 2155 ARM GIC. 2156 2157 This high priority configuration for interrupts needs to be 2158 explicitly enabled by setting the kernel parameter 2159 "irqchip.gicv3_pseudo_nmi" to 1. 2160 2161 If unsure, say N 2162 2163if ARM64_PSEUDO_NMI 2164config ARM64_DEBUG_PRIORITY_MASKING 2165 bool "Debug interrupt priority masking" 2166 help 2167 This adds runtime checks to functions enabling/disabling 2168 interrupts when using priority masking. The additional checks verify 2169 the validity of ICC_PMR_EL1 when calling concerned functions. 2170 2171 If unsure, say N 2172endif # ARM64_PSEUDO_NMI 2173 2174config RELOCATABLE 2175 bool "Build a relocatable kernel image" if EXPERT 2176 select ARCH_HAS_RELR 2177 default y 2178 help 2179 This builds the kernel as a Position Independent Executable (PIE), 2180 which retains all relocation metadata required to relocate the 2181 kernel binary at runtime to a different virtual address than the 2182 address it was linked at. 2183 Since AArch64 uses the RELA relocation format, this requires a 2184 relocation pass at runtime even if the kernel is loaded at the 2185 same address it was linked at. 2186 2187config RANDOMIZE_BASE 2188 bool "Randomize the address of the kernel image" 2189 select ARM64_MODULE_PLTS if MODULES 2190 select RELOCATABLE 2191 help 2192 Randomizes the virtual address at which the kernel image is 2193 loaded, as a security feature that deters exploit attempts 2194 relying on knowledge of the location of kernel internals. 2195 2196 It is the bootloader's job to provide entropy, by passing a 2197 random u64 value in /chosen/kaslr-seed at kernel entry. 2198 2199 When booting via the UEFI stub, it will invoke the firmware's 2200 EFI_RNG_PROTOCOL implementation (if available) to supply entropy 2201 to the kernel proper. In addition, it will randomise the physical 2202 location of the kernel Image as well. 2203 2204 If unsure, say N. 2205 2206config RANDOMIZE_MODULE_REGION_FULL 2207 bool "Randomize the module region over a 2 GB range" 2208 depends on RANDOMIZE_BASE 2209 default y 2210 help 2211 Randomizes the location of the module region inside a 2 GB window 2212 covering the core kernel. This way, it is less likely for modules 2213 to leak information about the location of core kernel data structures 2214 but it does imply that function calls between modules and the core 2215 kernel will need to be resolved via veneers in the module PLT. 2216 2217 When this option is not set, the module region will be randomized over 2218 a limited range that contains the [_stext, _etext] interval of the 2219 core kernel, so branch relocations are almost always in range unless 2220 ARM64_MODULE_PLTS is enabled and the region is exhausted. In this 2221 particular case of region exhaustion, modules might be able to fall 2222 back to a larger 2GB area. 2223 2224config CC_HAVE_STACKPROTECTOR_SYSREG 2225 def_bool $(cc-option,-mstack-protector-guard=sysreg -mstack-protector-guard-reg=sp_el0 -mstack-protector-guard-offset=0) 2226 2227config STACKPROTECTOR_PER_TASK 2228 def_bool y 2229 depends on STACKPROTECTOR && CC_HAVE_STACKPROTECTOR_SYSREG 2230 2231config UNWIND_PATCH_PAC_INTO_SCS 2232 bool "Enable shadow call stack dynamically using code patching" 2233 # needs Clang with https://reviews.llvm.org/D111780 incorporated 2234 depends on CC_IS_CLANG && CLANG_VERSION >= 150000 2235 depends on ARM64_PTR_AUTH_KERNEL && CC_HAS_BRANCH_PROT_PAC_RET 2236 depends on SHADOW_CALL_STACK 2237 select UNWIND_TABLES 2238 select DYNAMIC_SCS 2239 2240endmenu # "Kernel Features" 2241 2242menu "Boot options" 2243 2244config ARM64_ACPI_PARKING_PROTOCOL 2245 bool "Enable support for the ARM64 ACPI parking protocol" 2246 depends on ACPI 2247 help 2248 Enable support for the ARM64 ACPI parking protocol. If disabled 2249 the kernel will not allow booting through the ARM64 ACPI parking 2250 protocol even if the corresponding data is present in the ACPI 2251 MADT table. 2252 2253config CMDLINE 2254 string "Default kernel command string" 2255 default "" 2256 help 2257 Provide a set of default command-line options at build time by 2258 entering them here. As a minimum, you should specify the the 2259 root device (e.g. root=/dev/nfs). 2260 2261choice 2262 prompt "Kernel command line type" if CMDLINE != "" 2263 default CMDLINE_FROM_BOOTLOADER 2264 help 2265 Choose how the kernel will handle the provided default kernel 2266 command line string. 2267 2268config CMDLINE_FROM_BOOTLOADER 2269 bool "Use bootloader kernel arguments if available" 2270 help 2271 Uses the command-line options passed by the boot loader. If 2272 the boot loader doesn't provide any, the default kernel command 2273 string provided in CMDLINE will be used. 2274 2275config CMDLINE_FORCE 2276 bool "Always use the default kernel command string" 2277 help 2278 Always use the default kernel command string, even if the boot 2279 loader passes other arguments to the kernel. 2280 This is useful if you cannot or don't want to change the 2281 command-line options your boot loader passes to the kernel. 2282 2283endchoice 2284 2285config EFI_STUB 2286 bool 2287 2288config EFI 2289 bool "UEFI runtime support" 2290 depends on OF && !CPU_BIG_ENDIAN 2291 depends on KERNEL_MODE_NEON 2292 select ARCH_SUPPORTS_ACPI 2293 select LIBFDT 2294 select UCS2_STRING 2295 select EFI_PARAMS_FROM_FDT 2296 select EFI_RUNTIME_WRAPPERS 2297 select EFI_STUB 2298 select EFI_GENERIC_STUB 2299 imply IMA_SECURE_AND_OR_TRUSTED_BOOT 2300 default y 2301 help 2302 This option provides support for runtime services provided 2303 by UEFI firmware (such as non-volatile variables, realtime 2304 clock, and platform reset). A UEFI stub is also provided to 2305 allow the kernel to be booted as an EFI application. This 2306 is only useful on systems that have UEFI firmware. 2307 2308config DMI 2309 bool "Enable support for SMBIOS (DMI) tables" 2310 depends on EFI 2311 default y 2312 help 2313 This enables SMBIOS/DMI feature for systems. 2314 2315 This option is only useful on systems that have UEFI firmware. 2316 However, even with this option, the resultant kernel should 2317 continue to boot on existing non-UEFI platforms. 2318 2319endmenu # "Boot options" 2320 2321menu "Power management options" 2322 2323source "kernel/power/Kconfig" 2324 2325config ARCH_HIBERNATION_POSSIBLE 2326 def_bool y 2327 depends on CPU_PM 2328 2329config ARCH_HIBERNATION_HEADER 2330 def_bool y 2331 depends on HIBERNATION 2332 2333config ARCH_SUSPEND_POSSIBLE 2334 def_bool y 2335 2336endmenu # "Power management options" 2337 2338menu "CPU Power Management" 2339 2340source "drivers/cpuidle/Kconfig" 2341 2342source "drivers/cpufreq/Kconfig" 2343 2344endmenu # "CPU Power Management" 2345 2346source "drivers/acpi/Kconfig" 2347 2348source "arch/arm64/kvm/Kconfig" 2349 2350