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