1config ARM64 2 def_bool y 3 select ACPI_CCA_REQUIRED if ACPI 4 select ACPI_GENERIC_GSI if ACPI 5 select ACPI_GTDT if ACPI 6 select ACPI_IORT if ACPI 7 select ACPI_REDUCED_HARDWARE_ONLY if ACPI 8 select ACPI_MCFG if ACPI 9 select ACPI_SPCR_TABLE if ACPI 10 select ARCH_CLOCKSOURCE_DATA 11 select ARCH_HAS_DEBUG_VIRTUAL 12 select ARCH_HAS_DEVMEM_IS_ALLOWED 13 select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI 14 select ARCH_HAS_ELF_RANDOMIZE 15 select ARCH_HAS_FORTIFY_SOURCE 16 select ARCH_HAS_GCOV_PROFILE_ALL 17 select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA 18 select ARCH_HAS_KCOV 19 select ARCH_HAS_SET_MEMORY 20 select ARCH_HAS_SG_CHAIN 21 select ARCH_HAS_STRICT_KERNEL_RWX 22 select ARCH_HAS_STRICT_MODULE_RWX 23 select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST 24 select ARCH_HAVE_NMI_SAFE_CMPXCHG if ACPI_APEI_SEA 25 select ARCH_INLINE_READ_LOCK if !PREEMPT 26 select ARCH_INLINE_READ_LOCK_BH if !PREEMPT 27 select ARCH_INLINE_READ_LOCK_IRQ if !PREEMPT 28 select ARCH_INLINE_READ_LOCK_IRQSAVE if !PREEMPT 29 select ARCH_INLINE_READ_UNLOCK if !PREEMPT 30 select ARCH_INLINE_READ_UNLOCK_BH if !PREEMPT 31 select ARCH_INLINE_READ_UNLOCK_IRQ if !PREEMPT 32 select ARCH_INLINE_READ_UNLOCK_IRQRESTORE if !PREEMPT 33 select ARCH_INLINE_WRITE_LOCK if !PREEMPT 34 select ARCH_INLINE_WRITE_LOCK_BH if !PREEMPT 35 select ARCH_INLINE_WRITE_LOCK_IRQ if !PREEMPT 36 select ARCH_INLINE_WRITE_LOCK_IRQSAVE if !PREEMPT 37 select ARCH_INLINE_WRITE_UNLOCK if !PREEMPT 38 select ARCH_INLINE_WRITE_UNLOCK_BH if !PREEMPT 39 select ARCH_INLINE_WRITE_UNLOCK_IRQ if !PREEMPT 40 select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE if !PREEMPT 41 select ARCH_USE_CMPXCHG_LOCKREF 42 select ARCH_USE_QUEUED_RWLOCKS 43 select ARCH_SUPPORTS_MEMORY_FAILURE 44 select ARCH_SUPPORTS_ATOMIC_RMW 45 select ARCH_SUPPORTS_NUMA_BALANCING 46 select ARCH_WANT_COMPAT_IPC_PARSE_VERSION 47 select ARCH_WANT_FRAME_POINTERS 48 select ARCH_HAS_UBSAN_SANITIZE_ALL 49 select ARM_AMBA 50 select ARM_ARCH_TIMER 51 select ARM_GIC 52 select AUDIT_ARCH_COMPAT_GENERIC 53 select ARM_GIC_V2M if PCI 54 select ARM_GIC_V3 55 select ARM_GIC_V3_ITS if PCI 56 select ARM_PSCI_FW 57 select BUILDTIME_EXTABLE_SORT 58 select CLONE_BACKWARDS 59 select COMMON_CLK 60 select CPU_PM if (SUSPEND || CPU_IDLE) 61 select DCACHE_WORD_ACCESS 62 select EDAC_SUPPORT 63 select FRAME_POINTER 64 select GENERIC_ALLOCATOR 65 select GENERIC_ARCH_TOPOLOGY 66 select GENERIC_CLOCKEVENTS 67 select GENERIC_CLOCKEVENTS_BROADCAST 68 select GENERIC_CPU_AUTOPROBE 69 select GENERIC_EARLY_IOREMAP 70 select GENERIC_IDLE_POLL_SETUP 71 select GENERIC_IRQ_PROBE 72 select GENERIC_IRQ_SHOW 73 select GENERIC_IRQ_SHOW_LEVEL 74 select GENERIC_PCI_IOMAP 75 select GENERIC_SCHED_CLOCK 76 select GENERIC_SMP_IDLE_THREAD 77 select GENERIC_STRNCPY_FROM_USER 78 select GENERIC_STRNLEN_USER 79 select GENERIC_TIME_VSYSCALL 80 select HANDLE_DOMAIN_IRQ 81 select HARDIRQS_SW_RESEND 82 select HAVE_ACPI_APEI if (ACPI && EFI) 83 select HAVE_ALIGNED_STRUCT_PAGE if SLUB 84 select HAVE_ARCH_AUDITSYSCALL 85 select HAVE_ARCH_BITREVERSE 86 select HAVE_ARCH_HUGE_VMAP 87 select HAVE_ARCH_JUMP_LABEL 88 select HAVE_ARCH_KASAN if SPARSEMEM_VMEMMAP && !(ARM64_16K_PAGES && ARM64_VA_BITS_48) 89 select HAVE_ARCH_KGDB 90 select HAVE_ARCH_MMAP_RND_BITS 91 select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT 92 select HAVE_ARCH_SECCOMP_FILTER 93 select HAVE_ARCH_TRACEHOOK 94 select HAVE_ARCH_TRANSPARENT_HUGEPAGE 95 select HAVE_ARCH_VMAP_STACK 96 select HAVE_ARM_SMCCC 97 select HAVE_EBPF_JIT 98 select HAVE_C_RECORDMCOUNT 99 select HAVE_CC_STACKPROTECTOR 100 select HAVE_CMPXCHG_DOUBLE 101 select HAVE_CMPXCHG_LOCAL 102 select HAVE_CONTEXT_TRACKING 103 select HAVE_DEBUG_BUGVERBOSE 104 select HAVE_DEBUG_KMEMLEAK 105 select HAVE_DMA_API_DEBUG 106 select HAVE_DMA_CONTIGUOUS 107 select HAVE_DYNAMIC_FTRACE 108 select HAVE_EFFICIENT_UNALIGNED_ACCESS 109 select HAVE_FTRACE_MCOUNT_RECORD 110 select HAVE_FUNCTION_TRACER 111 select HAVE_FUNCTION_GRAPH_TRACER 112 select HAVE_GCC_PLUGINS 113 select HAVE_GENERIC_DMA_COHERENT 114 select HAVE_HW_BREAKPOINT if PERF_EVENTS 115 select HAVE_IRQ_TIME_ACCOUNTING 116 select HAVE_MEMBLOCK 117 select HAVE_MEMBLOCK_NODE_MAP if NUMA 118 select HAVE_NMI if ACPI_APEI_SEA 119 select HAVE_PATA_PLATFORM 120 select HAVE_PERF_EVENTS 121 select HAVE_PERF_REGS 122 select HAVE_PERF_USER_STACK_DUMP 123 select HAVE_REGS_AND_STACK_ACCESS_API 124 select HAVE_RCU_TABLE_FREE 125 select HAVE_SYSCALL_TRACEPOINTS 126 select HAVE_KPROBES 127 select HAVE_KRETPROBES 128 select IOMMU_DMA if IOMMU_SUPPORT 129 select IRQ_DOMAIN 130 select IRQ_FORCED_THREADING 131 select MODULES_USE_ELF_RELA 132 select NO_BOOTMEM 133 select OF 134 select OF_EARLY_FLATTREE 135 select OF_RESERVED_MEM 136 select PCI_ECAM if ACPI 137 select POWER_RESET 138 select POWER_SUPPLY 139 select SPARSE_IRQ 140 select SYSCTL_EXCEPTION_TRACE 141 select THREAD_INFO_IN_TASK 142 help 143 ARM 64-bit (AArch64) Linux support. 144 145config 64BIT 146 def_bool y 147 148config ARCH_PHYS_ADDR_T_64BIT 149 def_bool y 150 151config MMU 152 def_bool y 153 154config ARM64_PAGE_SHIFT 155 int 156 default 16 if ARM64_64K_PAGES 157 default 14 if ARM64_16K_PAGES 158 default 12 159 160config ARM64_CONT_SHIFT 161 int 162 default 5 if ARM64_64K_PAGES 163 default 7 if ARM64_16K_PAGES 164 default 4 165 166config ARCH_MMAP_RND_BITS_MIN 167 default 14 if ARM64_64K_PAGES 168 default 16 if ARM64_16K_PAGES 169 default 18 170 171# max bits determined by the following formula: 172# VA_BITS - PAGE_SHIFT - 3 173config ARCH_MMAP_RND_BITS_MAX 174 default 19 if ARM64_VA_BITS=36 175 default 24 if ARM64_VA_BITS=39 176 default 27 if ARM64_VA_BITS=42 177 default 30 if ARM64_VA_BITS=47 178 default 29 if ARM64_VA_BITS=48 && ARM64_64K_PAGES 179 default 31 if ARM64_VA_BITS=48 && ARM64_16K_PAGES 180 default 33 if ARM64_VA_BITS=48 181 default 14 if ARM64_64K_PAGES 182 default 16 if ARM64_16K_PAGES 183 default 18 184 185config ARCH_MMAP_RND_COMPAT_BITS_MIN 186 default 7 if ARM64_64K_PAGES 187 default 9 if ARM64_16K_PAGES 188 default 11 189 190config ARCH_MMAP_RND_COMPAT_BITS_MAX 191 default 16 192 193config NO_IOPORT_MAP 194 def_bool y if !PCI 195 196config STACKTRACE_SUPPORT 197 def_bool y 198 199config ILLEGAL_POINTER_VALUE 200 hex 201 default 0xdead000000000000 202 203config LOCKDEP_SUPPORT 204 def_bool y 205 206config TRACE_IRQFLAGS_SUPPORT 207 def_bool y 208 209config RWSEM_XCHGADD_ALGORITHM 210 def_bool y 211 212config GENERIC_BUG 213 def_bool y 214 depends on BUG 215 216config GENERIC_BUG_RELATIVE_POINTERS 217 def_bool y 218 depends on GENERIC_BUG 219 220config GENERIC_HWEIGHT 221 def_bool y 222 223config GENERIC_CSUM 224 def_bool y 225 226config GENERIC_CALIBRATE_DELAY 227 def_bool y 228 229config ZONE_DMA 230 def_bool y 231 232config HAVE_GENERIC_GUP 233 def_bool y 234 235config ARCH_DMA_ADDR_T_64BIT 236 def_bool y 237 238config NEED_DMA_MAP_STATE 239 def_bool y 240 241config NEED_SG_DMA_LENGTH 242 def_bool y 243 244config SMP 245 def_bool y 246 247config SWIOTLB 248 def_bool y 249 250config IOMMU_HELPER 251 def_bool SWIOTLB 252 253config KERNEL_MODE_NEON 254 def_bool y 255 256config FIX_EARLYCON_MEM 257 def_bool y 258 259config PGTABLE_LEVELS 260 int 261 default 2 if ARM64_16K_PAGES && ARM64_VA_BITS_36 262 default 2 if ARM64_64K_PAGES && ARM64_VA_BITS_42 263 default 3 if ARM64_64K_PAGES && ARM64_VA_BITS_48 264 default 3 if ARM64_4K_PAGES && ARM64_VA_BITS_39 265 default 3 if ARM64_16K_PAGES && ARM64_VA_BITS_47 266 default 4 if !ARM64_64K_PAGES && ARM64_VA_BITS_48 267 268config ARCH_SUPPORTS_UPROBES 269 def_bool y 270 271config ARCH_PROC_KCORE_TEXT 272 def_bool y 273 274source "init/Kconfig" 275 276source "kernel/Kconfig.freezer" 277 278source "arch/arm64/Kconfig.platforms" 279 280menu "Bus support" 281 282config PCI 283 bool "PCI support" 284 help 285 This feature enables support for PCI bus system. If you say Y 286 here, the kernel will include drivers and infrastructure code 287 to support PCI bus devices. 288 289config PCI_DOMAINS 290 def_bool PCI 291 292config PCI_DOMAINS_GENERIC 293 def_bool PCI 294 295config PCI_SYSCALL 296 def_bool PCI 297 298source "drivers/pci/Kconfig" 299 300endmenu 301 302menu "Kernel Features" 303 304menu "ARM errata workarounds via the alternatives framework" 305 306config ARM64_ERRATUM_826319 307 bool "Cortex-A53: 826319: System might deadlock if a write cannot complete until read data is accepted" 308 default y 309 help 310 This option adds an alternative code sequence to work around ARM 311 erratum 826319 on Cortex-A53 parts up to r0p2 with an AMBA 4 ACE or 312 AXI master interface and an L2 cache. 313 314 If a Cortex-A53 uses an AMBA AXI4 ACE interface to other processors 315 and is unable to accept a certain write via this interface, it will 316 not progress on read data presented on the read data channel and the 317 system can deadlock. 318 319 The workaround promotes data cache clean instructions to 320 data cache clean-and-invalidate. 321 Please note that this does not necessarily enable the workaround, 322 as it depends on the alternative framework, which will only patch 323 the kernel if an affected CPU is detected. 324 325 If unsure, say Y. 326 327config ARM64_ERRATUM_827319 328 bool "Cortex-A53: 827319: Data cache clean instructions might cause overlapping transactions to the interconnect" 329 default y 330 help 331 This option adds an alternative code sequence to work around ARM 332 erratum 827319 on Cortex-A53 parts up to r0p2 with an AMBA 5 CHI 333 master interface and an L2 cache. 334 335 Under certain conditions this erratum can cause a clean line eviction 336 to occur at the same time as another transaction to the same address 337 on the AMBA 5 CHI interface, which can cause data corruption if the 338 interconnect reorders the two transactions. 339 340 The workaround promotes data cache clean instructions to 341 data cache clean-and-invalidate. 342 Please note that this does not necessarily enable the workaround, 343 as it depends on the alternative framework, which will only patch 344 the kernel if an affected CPU is detected. 345 346 If unsure, say Y. 347 348config ARM64_ERRATUM_824069 349 bool "Cortex-A53: 824069: Cache line might not be marked as clean after a CleanShared snoop" 350 default y 351 help 352 This option adds an alternative code sequence to work around ARM 353 erratum 824069 on Cortex-A53 parts up to r0p2 when it is connected 354 to a coherent interconnect. 355 356 If a Cortex-A53 processor is executing a store or prefetch for 357 write instruction at the same time as a processor in another 358 cluster is executing a cache maintenance operation to the same 359 address, then this erratum might cause a clean cache line to be 360 incorrectly marked as dirty. 361 362 The workaround promotes data cache clean instructions to 363 data cache clean-and-invalidate. 364 Please note that this option does not necessarily enable the 365 workaround, as it depends on the alternative framework, which will 366 only patch the kernel if an affected CPU is detected. 367 368 If unsure, say Y. 369 370config ARM64_ERRATUM_819472 371 bool "Cortex-A53: 819472: Store exclusive instructions might cause data corruption" 372 default y 373 help 374 This option adds an alternative code sequence to work around ARM 375 erratum 819472 on Cortex-A53 parts up to r0p1 with an L2 cache 376 present when it is connected to a coherent interconnect. 377 378 If the processor is executing a load and store exclusive sequence at 379 the same time as a processor in another cluster is executing a cache 380 maintenance operation to the same address, then this erratum might 381 cause data corruption. 382 383 The workaround promotes data cache clean instructions to 384 data cache clean-and-invalidate. 385 Please note that this does not necessarily enable the workaround, 386 as it depends on the alternative framework, which will only patch 387 the kernel if an affected CPU is detected. 388 389 If unsure, say Y. 390 391config ARM64_ERRATUM_832075 392 bool "Cortex-A57: 832075: possible deadlock on mixing exclusive memory accesses with device loads" 393 default y 394 help 395 This option adds an alternative code sequence to work around ARM 396 erratum 832075 on Cortex-A57 parts up to r1p2. 397 398 Affected Cortex-A57 parts might deadlock when exclusive load/store 399 instructions to Write-Back memory are mixed with Device loads. 400 401 The workaround is to promote device loads to use Load-Acquire 402 semantics. 403 Please note that this does not necessarily enable the workaround, 404 as it depends on the alternative framework, which will only patch 405 the kernel if an affected CPU is detected. 406 407 If unsure, say Y. 408 409config ARM64_ERRATUM_834220 410 bool "Cortex-A57: 834220: Stage 2 translation fault might be incorrectly reported in presence of a Stage 1 fault" 411 depends on KVM 412 default y 413 help 414 This option adds an alternative code sequence to work around ARM 415 erratum 834220 on Cortex-A57 parts up to r1p2. 416 417 Affected Cortex-A57 parts might report a Stage 2 translation 418 fault as the result of a Stage 1 fault for load crossing a 419 page boundary when there is a permission or device memory 420 alignment fault at Stage 1 and a translation fault at Stage 2. 421 422 The workaround is to verify that the Stage 1 translation 423 doesn't generate a fault before handling the Stage 2 fault. 424 Please note that this does not necessarily enable the workaround, 425 as it depends on the alternative framework, which will only patch 426 the kernel if an affected CPU is detected. 427 428 If unsure, say Y. 429 430config ARM64_ERRATUM_845719 431 bool "Cortex-A53: 845719: a load might read incorrect data" 432 depends on COMPAT 433 default y 434 help 435 This option adds an alternative code sequence to work around ARM 436 erratum 845719 on Cortex-A53 parts up to r0p4. 437 438 When running a compat (AArch32) userspace on an affected Cortex-A53 439 part, a load at EL0 from a virtual address that matches the bottom 32 440 bits of the virtual address used by a recent load at (AArch64) EL1 441 might return incorrect data. 442 443 The workaround is to write the contextidr_el1 register on exception 444 return to a 32-bit task. 445 Please note that this does not necessarily enable the workaround, 446 as it depends on the alternative framework, which will only patch 447 the kernel if an affected CPU is detected. 448 449 If unsure, say Y. 450 451config ARM64_ERRATUM_843419 452 bool "Cortex-A53: 843419: A load or store might access an incorrect address" 453 default y 454 select ARM64_MODULE_CMODEL_LARGE if MODULES 455 help 456 This option links the kernel with '--fix-cortex-a53-843419' and 457 builds modules using the large memory model in order to avoid the use 458 of the ADRP instruction, which can cause a subsequent memory access 459 to use an incorrect address on Cortex-A53 parts up to r0p4. 460 461 If unsure, say Y. 462 463config CAVIUM_ERRATUM_22375 464 bool "Cavium erratum 22375, 24313" 465 default y 466 help 467 Enable workaround for erratum 22375, 24313. 468 469 This implements two gicv3-its errata workarounds for ThunderX. Both 470 with small impact affecting only ITS table allocation. 471 472 erratum 22375: only alloc 8MB table size 473 erratum 24313: ignore memory access type 474 475 The fixes are in ITS initialization and basically ignore memory access 476 type and table size provided by the TYPER and BASER registers. 477 478 If unsure, say Y. 479 480config CAVIUM_ERRATUM_23144 481 bool "Cavium erratum 23144: ITS SYNC hang on dual socket system" 482 depends on NUMA 483 default y 484 help 485 ITS SYNC command hang for cross node io and collections/cpu mapping. 486 487 If unsure, say Y. 488 489config CAVIUM_ERRATUM_23154 490 bool "Cavium erratum 23154: Access to ICC_IAR1_EL1 is not sync'ed" 491 default y 492 help 493 The gicv3 of ThunderX requires a modified version for 494 reading the IAR status to ensure data synchronization 495 (access to icc_iar1_el1 is not sync'ed before and after). 496 497 If unsure, say Y. 498 499config CAVIUM_ERRATUM_27456 500 bool "Cavium erratum 27456: Broadcast TLBI instructions may cause icache corruption" 501 default y 502 help 503 On ThunderX T88 pass 1.x through 2.1 parts, broadcast TLBI 504 instructions may cause the icache to become corrupted if it 505 contains data for a non-current ASID. The fix is to 506 invalidate the icache when changing the mm context. 507 508 If unsure, say Y. 509 510config CAVIUM_ERRATUM_30115 511 bool "Cavium erratum 30115: Guest may disable interrupts in host" 512 default y 513 help 514 On ThunderX T88 pass 1.x through 2.2, T81 pass 1.0 through 515 1.2, and T83 Pass 1.0, KVM guest execution may disable 516 interrupts in host. Trapping both GICv3 group-0 and group-1 517 accesses sidesteps the issue. 518 519 If unsure, say Y. 520 521config QCOM_FALKOR_ERRATUM_1003 522 bool "Falkor E1003: Incorrect translation due to ASID change" 523 default y 524 select ARM64_PAN if ARM64_SW_TTBR0_PAN 525 help 526 On Falkor v1, an incorrect ASID may be cached in the TLB when ASID 527 and BADDR are changed together in TTBRx_EL1. The workaround for this 528 issue is to use a reserved ASID in cpu_do_switch_mm() before 529 switching to the new ASID. Saying Y here selects ARM64_PAN if 530 ARM64_SW_TTBR0_PAN is selected. This is done because implementing and 531 maintaining the E1003 workaround in the software PAN emulation code 532 would be an unnecessary complication. The affected Falkor v1 CPU 533 implements ARMv8.1 hardware PAN support and using hardware PAN 534 support versus software PAN emulation is mutually exclusive at 535 runtime. 536 537 If unsure, say Y. 538 539config QCOM_FALKOR_ERRATUM_1009 540 bool "Falkor E1009: Prematurely complete a DSB after a TLBI" 541 default y 542 help 543 On Falkor v1, the CPU may prematurely complete a DSB following a 544 TLBI xxIS invalidate maintenance operation. Repeat the TLBI operation 545 one more time to fix the issue. 546 547 If unsure, say Y. 548 549config QCOM_QDF2400_ERRATUM_0065 550 bool "QDF2400 E0065: Incorrect GITS_TYPER.ITT_Entry_size" 551 default y 552 help 553 On Qualcomm Datacenter Technologies QDF2400 SoC, ITS hardware reports 554 ITE size incorrectly. The GITS_TYPER.ITT_Entry_size field should have 555 been indicated as 16Bytes (0xf), not 8Bytes (0x7). 556 557 If unsure, say Y. 558 559endmenu 560 561 562choice 563 prompt "Page size" 564 default ARM64_4K_PAGES 565 help 566 Page size (translation granule) configuration. 567 568config ARM64_4K_PAGES 569 bool "4KB" 570 help 571 This feature enables 4KB pages support. 572 573config ARM64_16K_PAGES 574 bool "16KB" 575 help 576 The system will use 16KB pages support. AArch32 emulation 577 requires applications compiled with 16K (or a multiple of 16K) 578 aligned segments. 579 580config ARM64_64K_PAGES 581 bool "64KB" 582 help 583 This feature enables 64KB pages support (4KB by default) 584 allowing only two levels of page tables and faster TLB 585 look-up. AArch32 emulation requires applications compiled 586 with 64K aligned segments. 587 588endchoice 589 590choice 591 prompt "Virtual address space size" 592 default ARM64_VA_BITS_39 if ARM64_4K_PAGES 593 default ARM64_VA_BITS_47 if ARM64_16K_PAGES 594 default ARM64_VA_BITS_42 if ARM64_64K_PAGES 595 help 596 Allows choosing one of multiple possible virtual address 597 space sizes. The level of translation table is determined by 598 a combination of page size and virtual address space size. 599 600config ARM64_VA_BITS_36 601 bool "36-bit" if EXPERT 602 depends on ARM64_16K_PAGES 603 604config ARM64_VA_BITS_39 605 bool "39-bit" 606 depends on ARM64_4K_PAGES 607 608config ARM64_VA_BITS_42 609 bool "42-bit" 610 depends on ARM64_64K_PAGES 611 612config ARM64_VA_BITS_47 613 bool "47-bit" 614 depends on ARM64_16K_PAGES 615 616config ARM64_VA_BITS_48 617 bool "48-bit" 618 619endchoice 620 621config ARM64_VA_BITS 622 int 623 default 36 if ARM64_VA_BITS_36 624 default 39 if ARM64_VA_BITS_39 625 default 42 if ARM64_VA_BITS_42 626 default 47 if ARM64_VA_BITS_47 627 default 48 if ARM64_VA_BITS_48 628 629config CPU_BIG_ENDIAN 630 bool "Build big-endian kernel" 631 help 632 Say Y if you plan on running a kernel in big-endian mode. 633 634config SCHED_MC 635 bool "Multi-core scheduler support" 636 help 637 Multi-core scheduler support improves the CPU scheduler's decision 638 making when dealing with multi-core CPU chips at a cost of slightly 639 increased overhead in some places. If unsure say N here. 640 641config SCHED_SMT 642 bool "SMT scheduler support" 643 help 644 Improves the CPU scheduler's decision making when dealing with 645 MultiThreading at a cost of slightly increased overhead in some 646 places. If unsure say N here. 647 648config NR_CPUS 649 int "Maximum number of CPUs (2-4096)" 650 range 2 4096 651 # These have to remain sorted largest to smallest 652 default "64" 653 654config HOTPLUG_CPU 655 bool "Support for hot-pluggable CPUs" 656 select GENERIC_IRQ_MIGRATION 657 help 658 Say Y here to experiment with turning CPUs off and on. CPUs 659 can be controlled through /sys/devices/system/cpu. 660 661# Common NUMA Features 662config NUMA 663 bool "Numa Memory Allocation and Scheduler Support" 664 select ACPI_NUMA if ACPI 665 select OF_NUMA 666 help 667 Enable NUMA (Non Uniform Memory Access) support. 668 669 The kernel will try to allocate memory used by a CPU on the 670 local memory of the CPU and add some more 671 NUMA awareness to the kernel. 672 673config NODES_SHIFT 674 int "Maximum NUMA Nodes (as a power of 2)" 675 range 1 10 676 default "2" 677 depends on NEED_MULTIPLE_NODES 678 help 679 Specify the maximum number of NUMA Nodes available on the target 680 system. Increases memory reserved to accommodate various tables. 681 682config USE_PERCPU_NUMA_NODE_ID 683 def_bool y 684 depends on NUMA 685 686config HAVE_SETUP_PER_CPU_AREA 687 def_bool y 688 depends on NUMA 689 690config NEED_PER_CPU_EMBED_FIRST_CHUNK 691 def_bool y 692 depends on NUMA 693 694config HOLES_IN_ZONE 695 def_bool y 696 depends on NUMA 697 698source kernel/Kconfig.preempt 699source kernel/Kconfig.hz 700 701config ARCH_SUPPORTS_DEBUG_PAGEALLOC 702 def_bool y 703 704config ARCH_HAS_HOLES_MEMORYMODEL 705 def_bool y if SPARSEMEM 706 707config ARCH_SPARSEMEM_ENABLE 708 def_bool y 709 select SPARSEMEM_VMEMMAP_ENABLE 710 711config ARCH_SPARSEMEM_DEFAULT 712 def_bool ARCH_SPARSEMEM_ENABLE 713 714config ARCH_SELECT_MEMORY_MODEL 715 def_bool ARCH_SPARSEMEM_ENABLE 716 717config HAVE_ARCH_PFN_VALID 718 def_bool ARCH_HAS_HOLES_MEMORYMODEL || !SPARSEMEM 719 720config HW_PERF_EVENTS 721 def_bool y 722 depends on ARM_PMU 723 724config SYS_SUPPORTS_HUGETLBFS 725 def_bool y 726 727config ARCH_WANT_HUGE_PMD_SHARE 728 def_bool y if ARM64_4K_PAGES || (ARM64_16K_PAGES && !ARM64_VA_BITS_36) 729 730config ARCH_HAS_CACHE_LINE_SIZE 731 def_bool y 732 733source "mm/Kconfig" 734 735config SECCOMP 736 bool "Enable seccomp to safely compute untrusted bytecode" 737 ---help--- 738 This kernel feature is useful for number crunching applications 739 that may need to compute untrusted bytecode during their 740 execution. By using pipes or other transports made available to 741 the process as file descriptors supporting the read/write 742 syscalls, it's possible to isolate those applications in 743 their own address space using seccomp. Once seccomp is 744 enabled via prctl(PR_SET_SECCOMP), it cannot be disabled 745 and the task is only allowed to execute a few safe syscalls 746 defined by each seccomp mode. 747 748config PARAVIRT 749 bool "Enable paravirtualization code" 750 help 751 This changes the kernel so it can modify itself when it is run 752 under a hypervisor, potentially improving performance significantly 753 over full virtualization. 754 755config PARAVIRT_TIME_ACCOUNTING 756 bool "Paravirtual steal time accounting" 757 select PARAVIRT 758 default n 759 help 760 Select this option to enable fine granularity task steal time 761 accounting. Time spent executing other tasks in parallel with 762 the current vCPU is discounted from the vCPU power. To account for 763 that, there can be a small performance impact. 764 765 If in doubt, say N here. 766 767config KEXEC 768 depends on PM_SLEEP_SMP 769 select KEXEC_CORE 770 bool "kexec system call" 771 ---help--- 772 kexec is a system call that implements the ability to shutdown your 773 current kernel, and to start another kernel. It is like a reboot 774 but it is independent of the system firmware. And like a reboot 775 you can start any kernel with it, not just Linux. 776 777config CRASH_DUMP 778 bool "Build kdump crash kernel" 779 help 780 Generate crash dump after being started by kexec. This should 781 be normally only set in special crash dump kernels which are 782 loaded in the main kernel with kexec-tools into a specially 783 reserved region and then later executed after a crash by 784 kdump/kexec. 785 786 For more details see Documentation/kdump/kdump.txt 787 788config XEN_DOM0 789 def_bool y 790 depends on XEN 791 792config XEN 793 bool "Xen guest support on ARM64" 794 depends on ARM64 && OF 795 select SWIOTLB_XEN 796 select PARAVIRT 797 help 798 Say Y if you want to run Linux in a Virtual Machine on Xen on ARM64. 799 800config FORCE_MAX_ZONEORDER 801 int 802 default "14" if (ARM64_64K_PAGES && TRANSPARENT_HUGEPAGE) 803 default "12" if (ARM64_16K_PAGES && TRANSPARENT_HUGEPAGE) 804 default "11" 805 help 806 The kernel memory allocator divides physically contiguous memory 807 blocks into "zones", where each zone is a power of two number of 808 pages. This option selects the largest power of two that the kernel 809 keeps in the memory allocator. If you need to allocate very large 810 blocks of physically contiguous memory, then you may need to 811 increase this value. 812 813 This config option is actually maximum order plus one. For example, 814 a value of 11 means that the largest free memory block is 2^10 pages. 815 816 We make sure that we can allocate upto a HugePage size for each configuration. 817 Hence we have : 818 MAX_ORDER = (PMD_SHIFT - PAGE_SHIFT) + 1 => PAGE_SHIFT - 2 819 820 However for 4K, we choose a higher default value, 11 as opposed to 10, giving us 821 4M allocations matching the default size used by generic code. 822 823menuconfig ARMV8_DEPRECATED 824 bool "Emulate deprecated/obsolete ARMv8 instructions" 825 depends on COMPAT 826 help 827 Legacy software support may require certain instructions 828 that have been deprecated or obsoleted in the architecture. 829 830 Enable this config to enable selective emulation of these 831 features. 832 833 If unsure, say Y 834 835if ARMV8_DEPRECATED 836 837config SWP_EMULATION 838 bool "Emulate SWP/SWPB instructions" 839 help 840 ARMv8 obsoletes the use of A32 SWP/SWPB instructions such that 841 they are always undefined. Say Y here to enable software 842 emulation of these instructions for userspace using LDXR/STXR. 843 844 In some older versions of glibc [<=2.8] SWP is used during futex 845 trylock() operations with the assumption that the code will not 846 be preempted. This invalid assumption may be more likely to fail 847 with SWP emulation enabled, leading to deadlock of the user 848 application. 849 850 NOTE: when accessing uncached shared regions, LDXR/STXR rely 851 on an external transaction monitoring block called a global 852 monitor to maintain update atomicity. If your system does not 853 implement a global monitor, this option can cause programs that 854 perform SWP operations to uncached memory to deadlock. 855 856 If unsure, say Y 857 858config CP15_BARRIER_EMULATION 859 bool "Emulate CP15 Barrier instructions" 860 help 861 The CP15 barrier instructions - CP15ISB, CP15DSB, and 862 CP15DMB - are deprecated in ARMv8 (and ARMv7). It is 863 strongly recommended to use the ISB, DSB, and DMB 864 instructions instead. 865 866 Say Y here to enable software emulation of these 867 instructions for AArch32 userspace code. When this option is 868 enabled, CP15 barrier usage is traced which can help 869 identify software that needs updating. 870 871 If unsure, say Y 872 873config SETEND_EMULATION 874 bool "Emulate SETEND instruction" 875 help 876 The SETEND instruction alters the data-endianness of the 877 AArch32 EL0, and is deprecated in ARMv8. 878 879 Say Y here to enable software emulation of the instruction 880 for AArch32 userspace code. 881 882 Note: All the cpus on the system must have mixed endian support at EL0 883 for this feature to be enabled. If a new CPU - which doesn't support mixed 884 endian - is hotplugged in after this feature has been enabled, there could 885 be unexpected results in the applications. 886 887 If unsure, say Y 888endif 889 890config ARM64_SW_TTBR0_PAN 891 bool "Emulate Privileged Access Never using TTBR0_EL1 switching" 892 help 893 Enabling this option prevents the kernel from accessing 894 user-space memory directly by pointing TTBR0_EL1 to a reserved 895 zeroed area and reserved ASID. The user access routines 896 restore the valid TTBR0_EL1 temporarily. 897 898menu "ARMv8.1 architectural features" 899 900config ARM64_HW_AFDBM 901 bool "Support for hardware updates of the Access and Dirty page flags" 902 default y 903 help 904 The ARMv8.1 architecture extensions introduce support for 905 hardware updates of the access and dirty information in page 906 table entries. When enabled in TCR_EL1 (HA and HD bits) on 907 capable processors, accesses to pages with PTE_AF cleared will 908 set this bit instead of raising an access flag fault. 909 Similarly, writes to read-only pages with the DBM bit set will 910 clear the read-only bit (AP[2]) instead of raising a 911 permission fault. 912 913 Kernels built with this configuration option enabled continue 914 to work on pre-ARMv8.1 hardware and the performance impact is 915 minimal. If unsure, say Y. 916 917config ARM64_PAN 918 bool "Enable support for Privileged Access Never (PAN)" 919 default y 920 help 921 Privileged Access Never (PAN; part of the ARMv8.1 Extensions) 922 prevents the kernel or hypervisor from accessing user-space (EL0) 923 memory directly. 924 925 Choosing this option will cause any unprotected (not using 926 copy_to_user et al) memory access to fail with a permission fault. 927 928 The feature is detected at runtime, and will remain as a 'nop' 929 instruction if the cpu does not implement the feature. 930 931config ARM64_LSE_ATOMICS 932 bool "Atomic instructions" 933 help 934 As part of the Large System Extensions, ARMv8.1 introduces new 935 atomic instructions that are designed specifically to scale in 936 very large systems. 937 938 Say Y here to make use of these instructions for the in-kernel 939 atomic routines. This incurs a small overhead on CPUs that do 940 not support these instructions and requires the kernel to be 941 built with binutils >= 2.25. 942 943config ARM64_VHE 944 bool "Enable support for Virtualization Host Extensions (VHE)" 945 default y 946 help 947 Virtualization Host Extensions (VHE) allow the kernel to run 948 directly at EL2 (instead of EL1) on processors that support 949 it. This leads to better performance for KVM, as they reduce 950 the cost of the world switch. 951 952 Selecting this option allows the VHE feature to be detected 953 at runtime, and does not affect processors that do not 954 implement this feature. 955 956endmenu 957 958menu "ARMv8.2 architectural features" 959 960config ARM64_UAO 961 bool "Enable support for User Access Override (UAO)" 962 default y 963 help 964 User Access Override (UAO; part of the ARMv8.2 Extensions) 965 causes the 'unprivileged' variant of the load/store instructions to 966 be overriden to be privileged. 967 968 This option changes get_user() and friends to use the 'unprivileged' 969 variant of the load/store instructions. This ensures that user-space 970 really did have access to the supplied memory. When addr_limit is 971 set to kernel memory the UAO bit will be set, allowing privileged 972 access to kernel memory. 973 974 Choosing this option will cause copy_to_user() et al to use user-space 975 memory permissions. 976 977 The feature is detected at runtime, the kernel will use the 978 regular load/store instructions if the cpu does not implement the 979 feature. 980 981config ARM64_PMEM 982 bool "Enable support for persistent memory" 983 select ARCH_HAS_PMEM_API 984 select ARCH_HAS_UACCESS_FLUSHCACHE 985 help 986 Say Y to enable support for the persistent memory API based on the 987 ARMv8.2 DCPoP feature. 988 989 The feature is detected at runtime, and the kernel will use DC CVAC 990 operations if DC CVAP is not supported (following the behaviour of 991 DC CVAP itself if the system does not define a point of persistence). 992 993endmenu 994 995config ARM64_MODULE_CMODEL_LARGE 996 bool 997 998config ARM64_MODULE_PLTS 999 bool 1000 select ARM64_MODULE_CMODEL_LARGE 1001 select HAVE_MOD_ARCH_SPECIFIC 1002 1003config RELOCATABLE 1004 bool 1005 help 1006 This builds the kernel as a Position Independent Executable (PIE), 1007 which retains all relocation metadata required to relocate the 1008 kernel binary at runtime to a different virtual address than the 1009 address it was linked at. 1010 Since AArch64 uses the RELA relocation format, this requires a 1011 relocation pass at runtime even if the kernel is loaded at the 1012 same address it was linked at. 1013 1014config RANDOMIZE_BASE 1015 bool "Randomize the address of the kernel image" 1016 select ARM64_MODULE_PLTS if MODULES 1017 select RELOCATABLE 1018 help 1019 Randomizes the virtual address at which the kernel image is 1020 loaded, as a security feature that deters exploit attempts 1021 relying on knowledge of the location of kernel internals. 1022 1023 It is the bootloader's job to provide entropy, by passing a 1024 random u64 value in /chosen/kaslr-seed at kernel entry. 1025 1026 When booting via the UEFI stub, it will invoke the firmware's 1027 EFI_RNG_PROTOCOL implementation (if available) to supply entropy 1028 to the kernel proper. In addition, it will randomise the physical 1029 location of the kernel Image as well. 1030 1031 If unsure, say N. 1032 1033config RANDOMIZE_MODULE_REGION_FULL 1034 bool "Randomize the module region independently from the core kernel" 1035 depends on RANDOMIZE_BASE 1036 default y 1037 help 1038 Randomizes the location of the module region without considering the 1039 location of the core kernel. This way, it is impossible for modules 1040 to leak information about the location of core kernel data structures 1041 but it does imply that function calls between modules and the core 1042 kernel will need to be resolved via veneers in the module PLT. 1043 1044 When this option is not set, the module region will be randomized over 1045 a limited range that contains the [_stext, _etext] interval of the 1046 core kernel, so branch relocations are always in range. 1047 1048endmenu 1049 1050menu "Boot options" 1051 1052config ARM64_ACPI_PARKING_PROTOCOL 1053 bool "Enable support for the ARM64 ACPI parking protocol" 1054 depends on ACPI 1055 help 1056 Enable support for the ARM64 ACPI parking protocol. If disabled 1057 the kernel will not allow booting through the ARM64 ACPI parking 1058 protocol even if the corresponding data is present in the ACPI 1059 MADT table. 1060 1061config CMDLINE 1062 string "Default kernel command string" 1063 default "" 1064 help 1065 Provide a set of default command-line options at build time by 1066 entering them here. As a minimum, you should specify the the 1067 root device (e.g. root=/dev/nfs). 1068 1069config CMDLINE_FORCE 1070 bool "Always use the default kernel command string" 1071 help 1072 Always use the default kernel command string, even if the boot 1073 loader passes other arguments to the kernel. 1074 This is useful if you cannot or don't want to change the 1075 command-line options your boot loader passes to the kernel. 1076 1077config EFI_STUB 1078 bool 1079 1080config EFI 1081 bool "UEFI runtime support" 1082 depends on OF && !CPU_BIG_ENDIAN 1083 select LIBFDT 1084 select UCS2_STRING 1085 select EFI_PARAMS_FROM_FDT 1086 select EFI_RUNTIME_WRAPPERS 1087 select EFI_STUB 1088 select EFI_ARMSTUB 1089 default y 1090 help 1091 This option provides support for runtime services provided 1092 by UEFI firmware (such as non-volatile variables, realtime 1093 clock, and platform reset). A UEFI stub is also provided to 1094 allow the kernel to be booted as an EFI application. This 1095 is only useful on systems that have UEFI firmware. 1096 1097config DMI 1098 bool "Enable support for SMBIOS (DMI) tables" 1099 depends on EFI 1100 default y 1101 help 1102 This enables SMBIOS/DMI feature for systems. 1103 1104 This option is only useful on systems that have UEFI firmware. 1105 However, even with this option, the resultant kernel should 1106 continue to boot on existing non-UEFI platforms. 1107 1108endmenu 1109 1110menu "Userspace binary formats" 1111 1112source "fs/Kconfig.binfmt" 1113 1114config COMPAT 1115 bool "Kernel support for 32-bit EL0" 1116 depends on ARM64_4K_PAGES || EXPERT 1117 select COMPAT_BINFMT_ELF if BINFMT_ELF 1118 select HAVE_UID16 1119 select OLD_SIGSUSPEND3 1120 select COMPAT_OLD_SIGACTION 1121 help 1122 This option enables support for a 32-bit EL0 running under a 64-bit 1123 kernel at EL1. AArch32-specific components such as system calls, 1124 the user helper functions, VFP support and the ptrace interface are 1125 handled appropriately by the kernel. 1126 1127 If you use a page size other than 4KB (i.e, 16KB or 64KB), please be aware 1128 that you will only be able to execute AArch32 binaries that were compiled 1129 with page size aligned segments. 1130 1131 If you want to execute 32-bit userspace applications, say Y. 1132 1133config SYSVIPC_COMPAT 1134 def_bool y 1135 depends on COMPAT && SYSVIPC 1136 1137endmenu 1138 1139menu "Power management options" 1140 1141source "kernel/power/Kconfig" 1142 1143config ARCH_HIBERNATION_POSSIBLE 1144 def_bool y 1145 depends on CPU_PM 1146 1147config ARCH_HIBERNATION_HEADER 1148 def_bool y 1149 depends on HIBERNATION 1150 1151config ARCH_SUSPEND_POSSIBLE 1152 def_bool y 1153 1154endmenu 1155 1156menu "CPU Power Management" 1157 1158source "drivers/cpuidle/Kconfig" 1159 1160source "drivers/cpufreq/Kconfig" 1161 1162endmenu 1163 1164source "net/Kconfig" 1165 1166source "drivers/Kconfig" 1167 1168source "drivers/firmware/Kconfig" 1169 1170source "drivers/acpi/Kconfig" 1171 1172source "fs/Kconfig" 1173 1174source "arch/arm64/kvm/Kconfig" 1175 1176source "arch/arm64/Kconfig.debug" 1177 1178source "security/Kconfig" 1179 1180source "crypto/Kconfig" 1181if CRYPTO 1182source "arch/arm64/crypto/Kconfig" 1183endif 1184 1185source "lib/Kconfig" 1186