Kconfig 43 KB

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  1. config 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 ACPI_PPTT if ACPI
  11. select ARCH_CLOCKSOURCE_DATA
  12. select ARCH_HAS_DEBUG_VIRTUAL
  13. select ARCH_HAS_DEVMEM_IS_ALLOWED
  14. select ARCH_HAS_ACPI_TABLE_UPGRADE if ACPI
  15. select ARCH_HAS_ELF_RANDOMIZE
  16. select ARCH_HAS_FAST_MULTIPLIER
  17. select ARCH_HAS_FORTIFY_SOURCE
  18. select ARCH_HAS_GCOV_PROFILE_ALL
  19. select ARCH_HAS_GIGANTIC_PAGE if (MEMORY_ISOLATION && COMPACTION) || CMA
  20. select ARCH_HAS_KCOV
  21. select ARCH_HAS_MEMBARRIER_SYNC_CORE
  22. select ARCH_HAS_PTE_SPECIAL
  23. select ARCH_HAS_SET_MEMORY
  24. select ARCH_HAS_SG_CHAIN
  25. select ARCH_HAS_STRICT_KERNEL_RWX
  26. select ARCH_HAS_STRICT_MODULE_RWX
  27. select ARCH_HAS_SYSCALL_WRAPPER
  28. select ARCH_HAS_TICK_BROADCAST if GENERIC_CLOCKEVENTS_BROADCAST
  29. select ARCH_HAVE_NMI_SAFE_CMPXCHG
  30. select ARCH_INLINE_READ_LOCK if !PREEMPT
  31. select ARCH_INLINE_READ_LOCK_BH if !PREEMPT
  32. select ARCH_INLINE_READ_LOCK_IRQ if !PREEMPT
  33. select ARCH_INLINE_READ_LOCK_IRQSAVE if !PREEMPT
  34. select ARCH_INLINE_READ_UNLOCK if !PREEMPT
  35. select ARCH_INLINE_READ_UNLOCK_BH if !PREEMPT
  36. select ARCH_INLINE_READ_UNLOCK_IRQ if !PREEMPT
  37. select ARCH_INLINE_READ_UNLOCK_IRQRESTORE if !PREEMPT
  38. select ARCH_INLINE_WRITE_LOCK if !PREEMPT
  39. select ARCH_INLINE_WRITE_LOCK_BH if !PREEMPT
  40. select ARCH_INLINE_WRITE_LOCK_IRQ if !PREEMPT
  41. select ARCH_INLINE_WRITE_LOCK_IRQSAVE if !PREEMPT
  42. select ARCH_INLINE_WRITE_UNLOCK if !PREEMPT
  43. select ARCH_INLINE_WRITE_UNLOCK_BH if !PREEMPT
  44. select ARCH_INLINE_WRITE_UNLOCK_IRQ if !PREEMPT
  45. select ARCH_INLINE_WRITE_UNLOCK_IRQRESTORE if !PREEMPT
  46. select ARCH_INLINE_SPIN_TRYLOCK if !PREEMPT
  47. select ARCH_INLINE_SPIN_TRYLOCK_BH if !PREEMPT
  48. select ARCH_INLINE_SPIN_LOCK if !PREEMPT
  49. select ARCH_INLINE_SPIN_LOCK_BH if !PREEMPT
  50. select ARCH_INLINE_SPIN_LOCK_IRQ if !PREEMPT
  51. select ARCH_INLINE_SPIN_LOCK_IRQSAVE if !PREEMPT
  52. select ARCH_INLINE_SPIN_UNLOCK if !PREEMPT
  53. select ARCH_INLINE_SPIN_UNLOCK_BH if !PREEMPT
  54. select ARCH_INLINE_SPIN_UNLOCK_IRQ if !PREEMPT
  55. select ARCH_INLINE_SPIN_UNLOCK_IRQRESTORE if !PREEMPT
  56. select ARCH_USE_CMPXCHG_LOCKREF
  57. select ARCH_USE_QUEUED_RWLOCKS
  58. select ARCH_USE_QUEUED_SPINLOCKS
  59. select ARCH_SUPPORTS_MEMORY_FAILURE
  60. select ARCH_SUPPORTS_ATOMIC_RMW
  61. select ARCH_SUPPORTS_INT128 if GCC_VERSION >= 50000 || CC_IS_CLANG
  62. select ARCH_SUPPORTS_NUMA_BALANCING
  63. select ARCH_WANT_COMPAT_IPC_PARSE_VERSION
  64. select ARCH_WANT_FRAME_POINTERS
  65. select ARCH_HAS_UBSAN_SANITIZE_ALL
  66. select ARM_AMBA
  67. select ARM_ARCH_TIMER
  68. select ARM_GIC
  69. select AUDIT_ARCH_COMPAT_GENERIC
  70. select ARM_GIC_V2M if PCI
  71. select ARM_GIC_V3
  72. select ARM_GIC_V3_ITS if PCI
  73. select ARM_PSCI_FW
  74. select BUILDTIME_EXTABLE_SORT
  75. select CLONE_BACKWARDS
  76. select COMMON_CLK
  77. select CPU_PM if (SUSPEND || CPU_IDLE)
  78. select DCACHE_WORD_ACCESS
  79. select DMA_DIRECT_OPS
  80. select EDAC_SUPPORT
  81. select FRAME_POINTER
  82. select GENERIC_ALLOCATOR
  83. select GENERIC_ARCH_TOPOLOGY
  84. select GENERIC_CLOCKEVENTS
  85. select GENERIC_CLOCKEVENTS_BROADCAST
  86. select GENERIC_CPU_AUTOPROBE
  87. select GENERIC_CPU_VULNERABILITIES
  88. select GENERIC_EARLY_IOREMAP
  89. select GENERIC_IDLE_POLL_SETUP
  90. select GENERIC_IRQ_MULTI_HANDLER
  91. select GENERIC_IRQ_PROBE
  92. select GENERIC_IRQ_SHOW
  93. select GENERIC_IRQ_SHOW_LEVEL
  94. select GENERIC_PCI_IOMAP
  95. select GENERIC_SCHED_CLOCK
  96. select GENERIC_SMP_IDLE_THREAD
  97. select GENERIC_STRNCPY_FROM_USER
  98. select GENERIC_STRNLEN_USER
  99. select GENERIC_TIME_VSYSCALL
  100. select HANDLE_DOMAIN_IRQ
  101. select HARDIRQS_SW_RESEND
  102. select HAVE_ACPI_APEI if (ACPI && EFI)
  103. select HAVE_ALIGNED_STRUCT_PAGE if SLUB
  104. select HAVE_ARCH_AUDITSYSCALL
  105. select HAVE_ARCH_BITREVERSE
  106. select HAVE_ARCH_HUGE_VMAP
  107. select HAVE_ARCH_JUMP_LABEL
  108. select HAVE_ARCH_KASAN if !(ARM64_16K_PAGES && ARM64_VA_BITS_48)
  109. select HAVE_ARCH_KGDB
  110. select HAVE_ARCH_MMAP_RND_BITS
  111. select HAVE_ARCH_MMAP_RND_COMPAT_BITS if COMPAT
  112. select HAVE_ARCH_PREL32_RELOCATIONS
  113. select HAVE_ARCH_SECCOMP_FILTER
  114. select HAVE_ARCH_STACKLEAK
  115. select HAVE_ARCH_THREAD_STRUCT_WHITELIST
  116. select HAVE_ARCH_TRACEHOOK
  117. select HAVE_ARCH_TRANSPARENT_HUGEPAGE
  118. select HAVE_ARCH_VMAP_STACK
  119. select HAVE_ARM_SMCCC
  120. select HAVE_EBPF_JIT
  121. select HAVE_C_RECORDMCOUNT
  122. select HAVE_CMPXCHG_DOUBLE
  123. select HAVE_CMPXCHG_LOCAL
  124. select HAVE_CONTEXT_TRACKING
  125. select HAVE_DEBUG_BUGVERBOSE
  126. select HAVE_DEBUG_KMEMLEAK
  127. select HAVE_DMA_CONTIGUOUS
  128. select HAVE_DYNAMIC_FTRACE
  129. select HAVE_EFFICIENT_UNALIGNED_ACCESS
  130. select HAVE_FTRACE_MCOUNT_RECORD
  131. select HAVE_FUNCTION_TRACER
  132. select HAVE_FUNCTION_GRAPH_TRACER
  133. select HAVE_GCC_PLUGINS
  134. select HAVE_GENERIC_DMA_COHERENT
  135. select HAVE_HW_BREAKPOINT if PERF_EVENTS
  136. select HAVE_IRQ_TIME_ACCOUNTING
  137. select HAVE_MEMBLOCK
  138. select HAVE_MEMBLOCK_NODE_MAP if NUMA
  139. select HAVE_NMI
  140. select HAVE_PATA_PLATFORM
  141. select HAVE_PERF_EVENTS
  142. select HAVE_PERF_REGS
  143. select HAVE_PERF_USER_STACK_DUMP
  144. select HAVE_REGS_AND_STACK_ACCESS_API
  145. select HAVE_RCU_TABLE_FREE
  146. select HAVE_RSEQ
  147. select HAVE_STACKPROTECTOR
  148. select HAVE_SYSCALL_TRACEPOINTS
  149. select HAVE_KPROBES
  150. select HAVE_KRETPROBES
  151. select IOMMU_DMA if IOMMU_SUPPORT
  152. select IRQ_DOMAIN
  153. select IRQ_FORCED_THREADING
  154. select MODULES_USE_ELF_RELA
  155. select MULTI_IRQ_HANDLER
  156. select NEED_DMA_MAP_STATE
  157. select NEED_SG_DMA_LENGTH
  158. select NO_BOOTMEM
  159. select OF
  160. select OF_EARLY_FLATTREE
  161. select OF_RESERVED_MEM
  162. select PCI_ECAM if ACPI
  163. select POWER_RESET
  164. select POWER_SUPPLY
  165. select REFCOUNT_FULL
  166. select SPARSE_IRQ
  167. select SWIOTLB
  168. select SYSCTL_EXCEPTION_TRACE
  169. select THREAD_INFO_IN_TASK
  170. help
  171. ARM 64-bit (AArch64) Linux support.
  172. config 64BIT
  173. def_bool y
  174. config MMU
  175. def_bool y
  176. config ARM64_PAGE_SHIFT
  177. int
  178. default 16 if ARM64_64K_PAGES
  179. default 14 if ARM64_16K_PAGES
  180. default 12
  181. config ARM64_CONT_SHIFT
  182. int
  183. default 5 if ARM64_64K_PAGES
  184. default 7 if ARM64_16K_PAGES
  185. default 4
  186. config ARCH_MMAP_RND_BITS_MIN
  187. default 14 if ARM64_64K_PAGES
  188. default 16 if ARM64_16K_PAGES
  189. default 18
  190. # max bits determined by the following formula:
  191. # VA_BITS - PAGE_SHIFT - 3
  192. config ARCH_MMAP_RND_BITS_MAX
  193. default 19 if ARM64_VA_BITS=36
  194. default 24 if ARM64_VA_BITS=39
  195. default 27 if ARM64_VA_BITS=42
  196. default 30 if ARM64_VA_BITS=47
  197. default 29 if ARM64_VA_BITS=48 && ARM64_64K_PAGES
  198. default 31 if ARM64_VA_BITS=48 && ARM64_16K_PAGES
  199. default 33 if ARM64_VA_BITS=48
  200. default 14 if ARM64_64K_PAGES
  201. default 16 if ARM64_16K_PAGES
  202. default 18
  203. config ARCH_MMAP_RND_COMPAT_BITS_MIN
  204. default 7 if ARM64_64K_PAGES
  205. default 9 if ARM64_16K_PAGES
  206. default 11
  207. config ARCH_MMAP_RND_COMPAT_BITS_MAX
  208. default 16
  209. config NO_IOPORT_MAP
  210. def_bool y if !PCI
  211. config STACKTRACE_SUPPORT
  212. def_bool y
  213. config ILLEGAL_POINTER_VALUE
  214. hex
  215. default 0xdead000000000000
  216. config LOCKDEP_SUPPORT
  217. def_bool y
  218. config TRACE_IRQFLAGS_SUPPORT
  219. def_bool y
  220. config RWSEM_XCHGADD_ALGORITHM
  221. def_bool y
  222. config GENERIC_BUG
  223. def_bool y
  224. depends on BUG
  225. config GENERIC_BUG_RELATIVE_POINTERS
  226. def_bool y
  227. depends on GENERIC_BUG
  228. config GENERIC_HWEIGHT
  229. def_bool y
  230. config GENERIC_CSUM
  231. def_bool y
  232. config GENERIC_CALIBRATE_DELAY
  233. def_bool y
  234. config ZONE_DMA32
  235. bool "Support DMA32 zone" if EXPERT
  236. default y
  237. config HAVE_GENERIC_GUP
  238. def_bool y
  239. config SMP
  240. def_bool y
  241. config KERNEL_MODE_NEON
  242. def_bool y
  243. config FIX_EARLYCON_MEM
  244. def_bool y
  245. config PGTABLE_LEVELS
  246. int
  247. default 2 if ARM64_16K_PAGES && ARM64_VA_BITS_36
  248. default 2 if ARM64_64K_PAGES && ARM64_VA_BITS_42
  249. default 3 if ARM64_64K_PAGES && ARM64_VA_BITS_48
  250. default 3 if ARM64_4K_PAGES && ARM64_VA_BITS_39
  251. default 3 if ARM64_16K_PAGES && ARM64_VA_BITS_47
  252. default 4 if !ARM64_64K_PAGES && ARM64_VA_BITS_48
  253. config ARCH_SUPPORTS_UPROBES
  254. def_bool y
  255. config ARCH_PROC_KCORE_TEXT
  256. def_bool y
  257. source "arch/arm64/Kconfig.platforms"
  258. menu "Bus support"
  259. config PCI
  260. bool "PCI support"
  261. help
  262. This feature enables support for PCI bus system. If you say Y
  263. here, the kernel will include drivers and infrastructure code
  264. to support PCI bus devices.
  265. config PCI_DOMAINS
  266. def_bool PCI
  267. config PCI_DOMAINS_GENERIC
  268. def_bool PCI
  269. config PCI_SYSCALL
  270. def_bool PCI
  271. source "drivers/pci/Kconfig"
  272. endmenu
  273. menu "Kernel Features"
  274. menu "ARM errata workarounds via the alternatives framework"
  275. config ARM64_ERRATUM_826319
  276. bool "Cortex-A53: 826319: System might deadlock if a write cannot complete until read data is accepted"
  277. default y
  278. help
  279. This option adds an alternative code sequence to work around ARM
  280. erratum 826319 on Cortex-A53 parts up to r0p2 with an AMBA 4 ACE or
  281. AXI master interface and an L2 cache.
  282. If a Cortex-A53 uses an AMBA AXI4 ACE interface to other processors
  283. and is unable to accept a certain write via this interface, it will
  284. not progress on read data presented on the read data channel and the
  285. system can deadlock.
  286. The workaround promotes data cache clean instructions to
  287. data cache clean-and-invalidate.
  288. Please note that this does not necessarily enable the workaround,
  289. as it depends on the alternative framework, which will only patch
  290. the kernel if an affected CPU is detected.
  291. If unsure, say Y.
  292. config ARM64_ERRATUM_827319
  293. bool "Cortex-A53: 827319: Data cache clean instructions might cause overlapping transactions to the interconnect"
  294. default y
  295. help
  296. This option adds an alternative code sequence to work around ARM
  297. erratum 827319 on Cortex-A53 parts up to r0p2 with an AMBA 5 CHI
  298. master interface and an L2 cache.
  299. Under certain conditions this erratum can cause a clean line eviction
  300. to occur at the same time as another transaction to the same address
  301. on the AMBA 5 CHI interface, which can cause data corruption if the
  302. interconnect reorders the two transactions.
  303. The workaround promotes data cache clean instructions to
  304. data cache clean-and-invalidate.
  305. Please note that this does not necessarily enable the workaround,
  306. as it depends on the alternative framework, which will only patch
  307. the kernel if an affected CPU is detected.
  308. If unsure, say Y.
  309. config ARM64_ERRATUM_824069
  310. bool "Cortex-A53: 824069: Cache line might not be marked as clean after a CleanShared snoop"
  311. default y
  312. help
  313. This option adds an alternative code sequence to work around ARM
  314. erratum 824069 on Cortex-A53 parts up to r0p2 when it is connected
  315. to a coherent interconnect.
  316. If a Cortex-A53 processor is executing a store or prefetch for
  317. write instruction at the same time as a processor in another
  318. cluster is executing a cache maintenance operation to the same
  319. address, then this erratum might cause a clean cache line to be
  320. incorrectly marked as dirty.
  321. The workaround promotes data cache clean instructions to
  322. data cache clean-and-invalidate.
  323. Please note that this option does not necessarily enable the
  324. workaround, as it depends on the alternative framework, which will
  325. only patch the kernel if an affected CPU is detected.
  326. If unsure, say Y.
  327. config ARM64_ERRATUM_819472
  328. bool "Cortex-A53: 819472: Store exclusive instructions might cause data corruption"
  329. default y
  330. help
  331. This option adds an alternative code sequence to work around ARM
  332. erratum 819472 on Cortex-A53 parts up to r0p1 with an L2 cache
  333. present when it is connected to a coherent interconnect.
  334. If the processor is executing a load and store exclusive sequence at
  335. the same time as a processor in another cluster is executing a cache
  336. maintenance operation to the same address, then this erratum might
  337. cause data corruption.
  338. The workaround promotes data cache clean instructions to
  339. data cache clean-and-invalidate.
  340. Please note that this does not necessarily enable the workaround,
  341. as it depends on the alternative framework, which will only patch
  342. the kernel if an affected CPU is detected.
  343. If unsure, say Y.
  344. config ARM64_ERRATUM_832075
  345. bool "Cortex-A57: 832075: possible deadlock on mixing exclusive memory accesses with device loads"
  346. default y
  347. help
  348. This option adds an alternative code sequence to work around ARM
  349. erratum 832075 on Cortex-A57 parts up to r1p2.
  350. Affected Cortex-A57 parts might deadlock when exclusive load/store
  351. instructions to Write-Back memory are mixed with Device loads.
  352. The workaround is to promote device loads to use Load-Acquire
  353. semantics.
  354. Please note that this does not necessarily enable the workaround,
  355. as it depends on the alternative framework, which will only patch
  356. the kernel if an affected CPU is detected.
  357. If unsure, say Y.
  358. config ARM64_ERRATUM_834220
  359. bool "Cortex-A57: 834220: Stage 2 translation fault might be incorrectly reported in presence of a Stage 1 fault"
  360. depends on KVM
  361. default y
  362. help
  363. This option adds an alternative code sequence to work around ARM
  364. erratum 834220 on Cortex-A57 parts up to r1p2.
  365. Affected Cortex-A57 parts might report a Stage 2 translation
  366. fault as the result of a Stage 1 fault for load crossing a
  367. page boundary when there is a permission or device memory
  368. alignment fault at Stage 1 and a translation fault at Stage 2.
  369. The workaround is to verify that the Stage 1 translation
  370. doesn't generate a fault before handling the Stage 2 fault.
  371. Please note that this does not necessarily enable the workaround,
  372. as it depends on the alternative framework, which will only patch
  373. the kernel if an affected CPU is detected.
  374. If unsure, say Y.
  375. config ARM64_ERRATUM_845719
  376. bool "Cortex-A53: 845719: a load might read incorrect data"
  377. depends on COMPAT
  378. default y
  379. help
  380. This option adds an alternative code sequence to work around ARM
  381. erratum 845719 on Cortex-A53 parts up to r0p4.
  382. When running a compat (AArch32) userspace on an affected Cortex-A53
  383. part, a load at EL0 from a virtual address that matches the bottom 32
  384. bits of the virtual address used by a recent load at (AArch64) EL1
  385. might return incorrect data.
  386. The workaround is to write the contextidr_el1 register on exception
  387. return to a 32-bit task.
  388. Please note that this does not necessarily enable the workaround,
  389. as it depends on the alternative framework, which will only patch
  390. the kernel if an affected CPU is detected.
  391. If unsure, say Y.
  392. config ARM64_ERRATUM_843419
  393. bool "Cortex-A53: 843419: A load or store might access an incorrect address"
  394. default y
  395. select ARM64_MODULE_PLTS if MODULES
  396. help
  397. This option links the kernel with '--fix-cortex-a53-843419' and
  398. enables PLT support to replace certain ADRP instructions, which can
  399. cause subsequent memory accesses to use an incorrect address on
  400. Cortex-A53 parts up to r0p4.
  401. If unsure, say Y.
  402. config ARM64_ERRATUM_1024718
  403. bool "Cortex-A55: 1024718: Update of DBM/AP bits without break before make might result in incorrect update"
  404. default y
  405. help
  406. This option adds work around for Arm Cortex-A55 Erratum 1024718.
  407. Affected Cortex-A55 cores (all revisions) could cause incorrect
  408. update of the hardware dirty bit when the DBM/AP bits are updated
  409. without a break-before-make. The work around is to disable the usage
  410. of hardware DBM locally on the affected cores. CPUs not affected by
  411. erratum will continue to use the feature.
  412. If unsure, say Y.
  413. config ARM64_ERRATUM_1463225
  414. bool "Cortex-A76: Software Step might prevent interrupt recognition"
  415. default y
  416. help
  417. This option adds a workaround for Arm Cortex-A76 erratum 1463225.
  418. On the affected Cortex-A76 cores (r0p0 to r3p1), software stepping
  419. of a system call instruction (SVC) can prevent recognition of
  420. subsequent interrupts when software stepping is disabled in the
  421. exception handler of the system call and either kernel debugging
  422. is enabled or VHE is in use.
  423. Work around the erratum by triggering a dummy step exception
  424. when handling a system call from a task that is being stepped
  425. in a VHE configuration of the kernel.
  426. If unsure, say Y.
  427. config ARM64_ERRATUM_1542419
  428. bool "Neoverse-N1: workaround mis-ordering of instruction fetches"
  429. default y
  430. help
  431. This option adds a workaround for ARM Neoverse-N1 erratum
  432. 1542419.
  433. Affected Neoverse-N1 cores could execute a stale instruction when
  434. modified by another CPU. The workaround depends on a firmware
  435. counterpart.
  436. Workaround the issue by hiding the DIC feature from EL0. This
  437. forces user-space to perform cache maintenance.
  438. If unsure, say Y.
  439. config CAVIUM_ERRATUM_22375
  440. bool "Cavium erratum 22375, 24313"
  441. default y
  442. help
  443. Enable workaround for erratum 22375, 24313.
  444. This implements two gicv3-its errata workarounds for ThunderX. Both
  445. with small impact affecting only ITS table allocation.
  446. erratum 22375: only alloc 8MB table size
  447. erratum 24313: ignore memory access type
  448. The fixes are in ITS initialization and basically ignore memory access
  449. type and table size provided by the TYPER and BASER registers.
  450. If unsure, say Y.
  451. config CAVIUM_ERRATUM_23144
  452. bool "Cavium erratum 23144: ITS SYNC hang on dual socket system"
  453. depends on NUMA
  454. default y
  455. help
  456. ITS SYNC command hang for cross node io and collections/cpu mapping.
  457. If unsure, say Y.
  458. config CAVIUM_ERRATUM_23154
  459. bool "Cavium erratum 23154: Access to ICC_IAR1_EL1 is not sync'ed"
  460. default y
  461. help
  462. The gicv3 of ThunderX requires a modified version for
  463. reading the IAR status to ensure data synchronization
  464. (access to icc_iar1_el1 is not sync'ed before and after).
  465. If unsure, say Y.
  466. config CAVIUM_ERRATUM_27456
  467. bool "Cavium erratum 27456: Broadcast TLBI instructions may cause icache corruption"
  468. default y
  469. help
  470. On ThunderX T88 pass 1.x through 2.1 parts, broadcast TLBI
  471. instructions may cause the icache to become corrupted if it
  472. contains data for a non-current ASID. The fix is to
  473. invalidate the icache when changing the mm context.
  474. If unsure, say Y.
  475. config CAVIUM_ERRATUM_30115
  476. bool "Cavium erratum 30115: Guest may disable interrupts in host"
  477. default y
  478. help
  479. On ThunderX T88 pass 1.x through 2.2, T81 pass 1.0 through
  480. 1.2, and T83 Pass 1.0, KVM guest execution may disable
  481. interrupts in host. Trapping both GICv3 group-0 and group-1
  482. accesses sidesteps the issue.
  483. If unsure, say Y.
  484. config QCOM_FALKOR_ERRATUM_1003
  485. bool "Falkor E1003: Incorrect translation due to ASID change"
  486. default y
  487. help
  488. On Falkor v1, an incorrect ASID may be cached in the TLB when ASID
  489. and BADDR are changed together in TTBRx_EL1. Since we keep the ASID
  490. in TTBR1_EL1, this situation only occurs in the entry trampoline and
  491. then only for entries in the walk cache, since the leaf translation
  492. is unchanged. Work around the erratum by invalidating the walk cache
  493. entries for the trampoline before entering the kernel proper.
  494. config QCOM_FALKOR_ERRATUM_1009
  495. bool "Falkor E1009: Prematurely complete a DSB after a TLBI"
  496. default y
  497. help
  498. On Falkor v1, the CPU may prematurely complete a DSB following a
  499. TLBI xxIS invalidate maintenance operation. Repeat the TLBI operation
  500. one more time to fix the issue.
  501. If unsure, say Y.
  502. config QCOM_QDF2400_ERRATUM_0065
  503. bool "QDF2400 E0065: Incorrect GITS_TYPER.ITT_Entry_size"
  504. default y
  505. help
  506. On Qualcomm Datacenter Technologies QDF2400 SoC, ITS hardware reports
  507. ITE size incorrectly. The GITS_TYPER.ITT_Entry_size field should have
  508. been indicated as 16Bytes (0xf), not 8Bytes (0x7).
  509. If unsure, say Y.
  510. config SOCIONEXT_SYNQUACER_PREITS
  511. bool "Socionext Synquacer: Workaround for GICv3 pre-ITS"
  512. default y
  513. help
  514. Socionext Synquacer SoCs implement a separate h/w block to generate
  515. MSI doorbell writes with non-zero values for the device ID.
  516. If unsure, say Y.
  517. config HISILICON_ERRATUM_161600802
  518. bool "Hip07 161600802: Erroneous redistributor VLPI base"
  519. default y
  520. help
  521. The HiSilicon Hip07 SoC usees the wrong redistributor base
  522. when issued ITS commands such as VMOVP and VMAPP, and requires
  523. a 128kB offset to be applied to the target address in this commands.
  524. If unsure, say Y.
  525. config QCOM_FALKOR_ERRATUM_E1041
  526. bool "Falkor E1041: Speculative instruction fetches might cause errant memory access"
  527. default y
  528. help
  529. Falkor CPU may speculatively fetch instructions from an improper
  530. memory location when MMU translation is changed from SCTLR_ELn[M]=1
  531. to SCTLR_ELn[M]=0. Prefix an ISB instruction to fix the problem.
  532. If unsure, say Y.
  533. endmenu
  534. choice
  535. prompt "Page size"
  536. default ARM64_4K_PAGES
  537. help
  538. Page size (translation granule) configuration.
  539. config ARM64_4K_PAGES
  540. bool "4KB"
  541. help
  542. This feature enables 4KB pages support.
  543. config ARM64_16K_PAGES
  544. bool "16KB"
  545. help
  546. The system will use 16KB pages support. AArch32 emulation
  547. requires applications compiled with 16K (or a multiple of 16K)
  548. aligned segments.
  549. config ARM64_64K_PAGES
  550. bool "64KB"
  551. help
  552. This feature enables 64KB pages support (4KB by default)
  553. allowing only two levels of page tables and faster TLB
  554. look-up. AArch32 emulation requires applications compiled
  555. with 64K aligned segments.
  556. endchoice
  557. choice
  558. prompt "Virtual address space size"
  559. default ARM64_VA_BITS_39 if ARM64_4K_PAGES
  560. default ARM64_VA_BITS_47 if ARM64_16K_PAGES
  561. default ARM64_VA_BITS_42 if ARM64_64K_PAGES
  562. help
  563. Allows choosing one of multiple possible virtual address
  564. space sizes. The level of translation table is determined by
  565. a combination of page size and virtual address space size.
  566. config ARM64_VA_BITS_36
  567. bool "36-bit" if EXPERT
  568. depends on ARM64_16K_PAGES
  569. config ARM64_VA_BITS_39
  570. bool "39-bit"
  571. depends on ARM64_4K_PAGES
  572. config ARM64_VA_BITS_42
  573. bool "42-bit"
  574. depends on ARM64_64K_PAGES
  575. config ARM64_VA_BITS_47
  576. bool "47-bit"
  577. depends on ARM64_16K_PAGES
  578. config ARM64_VA_BITS_48
  579. bool "48-bit"
  580. endchoice
  581. config ARM64_VA_BITS
  582. int
  583. default 36 if ARM64_VA_BITS_36
  584. default 39 if ARM64_VA_BITS_39
  585. default 42 if ARM64_VA_BITS_42
  586. default 47 if ARM64_VA_BITS_47
  587. default 48 if ARM64_VA_BITS_48
  588. choice
  589. prompt "Physical address space size"
  590. default ARM64_PA_BITS_48
  591. help
  592. Choose the maximum physical address range that the kernel will
  593. support.
  594. config ARM64_PA_BITS_48
  595. bool "48-bit"
  596. config ARM64_PA_BITS_52
  597. bool "52-bit (ARMv8.2)"
  598. depends on ARM64_64K_PAGES
  599. depends on ARM64_PAN || !ARM64_SW_TTBR0_PAN
  600. help
  601. Enable support for a 52-bit physical address space, introduced as
  602. part of the ARMv8.2-LPA extension.
  603. With this enabled, the kernel will also continue to work on CPUs that
  604. do not support ARMv8.2-LPA, but with some added memory overhead (and
  605. minor performance overhead).
  606. endchoice
  607. config ARM64_PA_BITS
  608. int
  609. default 48 if ARM64_PA_BITS_48
  610. default 52 if ARM64_PA_BITS_52
  611. config CPU_BIG_ENDIAN
  612. bool "Build big-endian kernel"
  613. help
  614. Say Y if you plan on running a kernel in big-endian mode.
  615. config SCHED_MC
  616. bool "Multi-core scheduler support"
  617. help
  618. Multi-core scheduler support improves the CPU scheduler's decision
  619. making when dealing with multi-core CPU chips at a cost of slightly
  620. increased overhead in some places. If unsure say N here.
  621. config SCHED_SMT
  622. bool "SMT scheduler support"
  623. help
  624. Improves the CPU scheduler's decision making when dealing with
  625. MultiThreading at a cost of slightly increased overhead in some
  626. places. If unsure say N here.
  627. config NR_CPUS
  628. int "Maximum number of CPUs (2-4096)"
  629. range 2 4096
  630. # These have to remain sorted largest to smallest
  631. default "64"
  632. config HOTPLUG_CPU
  633. bool "Support for hot-pluggable CPUs"
  634. select GENERIC_IRQ_MIGRATION
  635. help
  636. Say Y here to experiment with turning CPUs off and on. CPUs
  637. can be controlled through /sys/devices/system/cpu.
  638. # Common NUMA Features
  639. config NUMA
  640. bool "Numa Memory Allocation and Scheduler Support"
  641. select ACPI_NUMA if ACPI
  642. select OF_NUMA
  643. help
  644. Enable NUMA (Non Uniform Memory Access) support.
  645. The kernel will try to allocate memory used by a CPU on the
  646. local memory of the CPU and add some more
  647. NUMA awareness to the kernel.
  648. config NODES_SHIFT
  649. int "Maximum NUMA Nodes (as a power of 2)"
  650. range 1 10
  651. default "2"
  652. depends on NEED_MULTIPLE_NODES
  653. help
  654. Specify the maximum number of NUMA Nodes available on the target
  655. system. Increases memory reserved to accommodate various tables.
  656. config USE_PERCPU_NUMA_NODE_ID
  657. def_bool y
  658. depends on NUMA
  659. config HAVE_SETUP_PER_CPU_AREA
  660. def_bool y
  661. depends on NUMA
  662. config NEED_PER_CPU_EMBED_FIRST_CHUNK
  663. def_bool y
  664. depends on NUMA
  665. config HOLES_IN_ZONE
  666. def_bool y
  667. source kernel/Kconfig.hz
  668. config ARCH_SUPPORTS_DEBUG_PAGEALLOC
  669. def_bool y
  670. config ARCH_HAS_HOLES_MEMORYMODEL
  671. def_bool y if SPARSEMEM
  672. config ARCH_SPARSEMEM_ENABLE
  673. def_bool y
  674. select SPARSEMEM_VMEMMAP_ENABLE
  675. config ARCH_SPARSEMEM_DEFAULT
  676. def_bool ARCH_SPARSEMEM_ENABLE
  677. config ARCH_SELECT_MEMORY_MODEL
  678. def_bool ARCH_SPARSEMEM_ENABLE
  679. config ARCH_FLATMEM_ENABLE
  680. def_bool !NUMA
  681. config HAVE_ARCH_PFN_VALID
  682. def_bool ARCH_HAS_HOLES_MEMORYMODEL || !SPARSEMEM
  683. config HW_PERF_EVENTS
  684. def_bool y
  685. depends on ARM_PMU
  686. config SYS_SUPPORTS_HUGETLBFS
  687. def_bool y
  688. config ARCH_WANT_HUGE_PMD_SHARE
  689. def_bool y if ARM64_4K_PAGES || (ARM64_16K_PAGES && !ARM64_VA_BITS_36)
  690. config ARCH_HAS_CACHE_LINE_SIZE
  691. def_bool y
  692. config SECCOMP
  693. bool "Enable seccomp to safely compute untrusted bytecode"
  694. ---help---
  695. This kernel feature is useful for number crunching applications
  696. that may need to compute untrusted bytecode during their
  697. execution. By using pipes or other transports made available to
  698. the process as file descriptors supporting the read/write
  699. syscalls, it's possible to isolate those applications in
  700. their own address space using seccomp. Once seccomp is
  701. enabled via prctl(PR_SET_SECCOMP), it cannot be disabled
  702. and the task is only allowed to execute a few safe syscalls
  703. defined by each seccomp mode.
  704. config PARAVIRT
  705. bool "Enable paravirtualization code"
  706. help
  707. This changes the kernel so it can modify itself when it is run
  708. under a hypervisor, potentially improving performance significantly
  709. over full virtualization.
  710. config PARAVIRT_TIME_ACCOUNTING
  711. bool "Paravirtual steal time accounting"
  712. select PARAVIRT
  713. default n
  714. help
  715. Select this option to enable fine granularity task steal time
  716. accounting. Time spent executing other tasks in parallel with
  717. the current vCPU is discounted from the vCPU power. To account for
  718. that, there can be a small performance impact.
  719. If in doubt, say N here.
  720. config KEXEC
  721. depends on PM_SLEEP_SMP
  722. select KEXEC_CORE
  723. bool "kexec system call"
  724. ---help---
  725. kexec is a system call that implements the ability to shutdown your
  726. current kernel, and to start another kernel. It is like a reboot
  727. but it is independent of the system firmware. And like a reboot
  728. you can start any kernel with it, not just Linux.
  729. config CRASH_DUMP
  730. bool "Build kdump crash kernel"
  731. help
  732. Generate crash dump after being started by kexec. This should
  733. be normally only set in special crash dump kernels which are
  734. loaded in the main kernel with kexec-tools into a specially
  735. reserved region and then later executed after a crash by
  736. kdump/kexec.
  737. For more details see Documentation/kdump/kdump.txt
  738. config XEN_DOM0
  739. def_bool y
  740. depends on XEN
  741. config XEN
  742. bool "Xen guest support on ARM64"
  743. depends on ARM64 && OF
  744. select SWIOTLB_XEN
  745. select PARAVIRT
  746. help
  747. Say Y if you want to run Linux in a Virtual Machine on Xen on ARM64.
  748. config FORCE_MAX_ZONEORDER
  749. int
  750. default "14" if (ARM64_64K_PAGES && TRANSPARENT_HUGEPAGE)
  751. default "12" if (ARM64_16K_PAGES && TRANSPARENT_HUGEPAGE)
  752. default "11"
  753. help
  754. The kernel memory allocator divides physically contiguous memory
  755. blocks into "zones", where each zone is a power of two number of
  756. pages. This option selects the largest power of two that the kernel
  757. keeps in the memory allocator. If you need to allocate very large
  758. blocks of physically contiguous memory, then you may need to
  759. increase this value.
  760. This config option is actually maximum order plus one. For example,
  761. a value of 11 means that the largest free memory block is 2^10 pages.
  762. We make sure that we can allocate upto a HugePage size for each configuration.
  763. Hence we have :
  764. MAX_ORDER = (PMD_SHIFT - PAGE_SHIFT) + 1 => PAGE_SHIFT - 2
  765. However for 4K, we choose a higher default value, 11 as opposed to 10, giving us
  766. 4M allocations matching the default size used by generic code.
  767. config UNMAP_KERNEL_AT_EL0
  768. bool "Unmap kernel when running in userspace (aka \"KAISER\")" if EXPERT
  769. default y
  770. help
  771. Speculation attacks against some high-performance processors can
  772. be used to bypass MMU permission checks and leak kernel data to
  773. userspace. This can be defended against by unmapping the kernel
  774. when running in userspace, mapping it back in on exception entry
  775. via a trampoline page in the vector table.
  776. If unsure, say Y.
  777. config HARDEN_BRANCH_PREDICTOR
  778. bool "Harden the branch predictor against aliasing attacks" if EXPERT
  779. default y
  780. help
  781. Speculation attacks against some high-performance processors rely on
  782. being able to manipulate the branch predictor for a victim context by
  783. executing aliasing branches in the attacker context. Such attacks
  784. can be partially mitigated against by clearing internal branch
  785. predictor state and limiting the prediction logic in some situations.
  786. This config option will take CPU-specific actions to harden the
  787. branch predictor against aliasing attacks and may rely on specific
  788. instruction sequences or control bits being set by the system
  789. firmware.
  790. If unsure, say Y.
  791. config HARDEN_EL2_VECTORS
  792. bool "Harden EL2 vector mapping against system register leak" if EXPERT
  793. default y
  794. help
  795. Speculation attacks against some high-performance processors can
  796. be used to leak privileged information such as the vector base
  797. register, resulting in a potential defeat of the EL2 layout
  798. randomization.
  799. This config option will map the vectors to a fixed location,
  800. independent of the EL2 code mapping, so that revealing VBAR_EL2
  801. to an attacker does not give away any extra information. This
  802. only gets enabled on affected CPUs.
  803. If unsure, say Y.
  804. config ARM64_SSBD
  805. bool "Speculative Store Bypass Disable" if EXPERT
  806. default y
  807. help
  808. This enables mitigation of the bypassing of previous stores
  809. by speculative loads.
  810. If unsure, say Y.
  811. menuconfig ARMV8_DEPRECATED
  812. bool "Emulate deprecated/obsolete ARMv8 instructions"
  813. depends on COMPAT
  814. depends on SYSCTL
  815. help
  816. Legacy software support may require certain instructions
  817. that have been deprecated or obsoleted in the architecture.
  818. Enable this config to enable selective emulation of these
  819. features.
  820. If unsure, say Y
  821. if ARMV8_DEPRECATED
  822. config SWP_EMULATION
  823. bool "Emulate SWP/SWPB instructions"
  824. help
  825. ARMv8 obsoletes the use of A32 SWP/SWPB instructions such that
  826. they are always undefined. Say Y here to enable software
  827. emulation of these instructions for userspace using LDXR/STXR.
  828. In some older versions of glibc [<=2.8] SWP is used during futex
  829. trylock() operations with the assumption that the code will not
  830. be preempted. This invalid assumption may be more likely to fail
  831. with SWP emulation enabled, leading to deadlock of the user
  832. application.
  833. NOTE: when accessing uncached shared regions, LDXR/STXR rely
  834. on an external transaction monitoring block called a global
  835. monitor to maintain update atomicity. If your system does not
  836. implement a global monitor, this option can cause programs that
  837. perform SWP operations to uncached memory to deadlock.
  838. If unsure, say Y
  839. config CP15_BARRIER_EMULATION
  840. bool "Emulate CP15 Barrier instructions"
  841. help
  842. The CP15 barrier instructions - CP15ISB, CP15DSB, and
  843. CP15DMB - are deprecated in ARMv8 (and ARMv7). It is
  844. strongly recommended to use the ISB, DSB, and DMB
  845. instructions instead.
  846. Say Y here to enable software emulation of these
  847. instructions for AArch32 userspace code. When this option is
  848. enabled, CP15 barrier usage is traced which can help
  849. identify software that needs updating.
  850. If unsure, say Y
  851. config SETEND_EMULATION
  852. bool "Emulate SETEND instruction"
  853. help
  854. The SETEND instruction alters the data-endianness of the
  855. AArch32 EL0, and is deprecated in ARMv8.
  856. Say Y here to enable software emulation of the instruction
  857. for AArch32 userspace code.
  858. Note: All the cpus on the system must have mixed endian support at EL0
  859. for this feature to be enabled. If a new CPU - which doesn't support mixed
  860. endian - is hotplugged in after this feature has been enabled, there could
  861. be unexpected results in the applications.
  862. If unsure, say Y
  863. endif
  864. config ARM64_SW_TTBR0_PAN
  865. bool "Emulate Privileged Access Never using TTBR0_EL1 switching"
  866. help
  867. Enabling this option prevents the kernel from accessing
  868. user-space memory directly by pointing TTBR0_EL1 to a reserved
  869. zeroed area and reserved ASID. The user access routines
  870. restore the valid TTBR0_EL1 temporarily.
  871. menu "ARMv8.1 architectural features"
  872. config ARM64_HW_AFDBM
  873. bool "Support for hardware updates of the Access and Dirty page flags"
  874. default y
  875. help
  876. The ARMv8.1 architecture extensions introduce support for
  877. hardware updates of the access and dirty information in page
  878. table entries. When enabled in TCR_EL1 (HA and HD bits) on
  879. capable processors, accesses to pages with PTE_AF cleared will
  880. set this bit instead of raising an access flag fault.
  881. Similarly, writes to read-only pages with the DBM bit set will
  882. clear the read-only bit (AP[2]) instead of raising a
  883. permission fault.
  884. Kernels built with this configuration option enabled continue
  885. to work on pre-ARMv8.1 hardware and the performance impact is
  886. minimal. If unsure, say Y.
  887. config ARM64_PAN
  888. bool "Enable support for Privileged Access Never (PAN)"
  889. default y
  890. help
  891. Privileged Access Never (PAN; part of the ARMv8.1 Extensions)
  892. prevents the kernel or hypervisor from accessing user-space (EL0)
  893. memory directly.
  894. Choosing this option will cause any unprotected (not using
  895. copy_to_user et al) memory access to fail with a permission fault.
  896. The feature is detected at runtime, and will remain as a 'nop'
  897. instruction if the cpu does not implement the feature.
  898. config ARM64_LSE_ATOMICS
  899. bool "Atomic instructions"
  900. default y
  901. help
  902. As part of the Large System Extensions, ARMv8.1 introduces new
  903. atomic instructions that are designed specifically to scale in
  904. very large systems.
  905. Say Y here to make use of these instructions for the in-kernel
  906. atomic routines. This incurs a small overhead on CPUs that do
  907. not support these instructions and requires the kernel to be
  908. built with binutils >= 2.25 in order for the new instructions
  909. to be used.
  910. config ARM64_VHE
  911. bool "Enable support for Virtualization Host Extensions (VHE)"
  912. default y
  913. help
  914. Virtualization Host Extensions (VHE) allow the kernel to run
  915. directly at EL2 (instead of EL1) on processors that support
  916. it. This leads to better performance for KVM, as they reduce
  917. the cost of the world switch.
  918. Selecting this option allows the VHE feature to be detected
  919. at runtime, and does not affect processors that do not
  920. implement this feature.
  921. endmenu
  922. menu "ARMv8.2 architectural features"
  923. config ARM64_UAO
  924. bool "Enable support for User Access Override (UAO)"
  925. default y
  926. help
  927. User Access Override (UAO; part of the ARMv8.2 Extensions)
  928. causes the 'unprivileged' variant of the load/store instructions to
  929. be overridden to be privileged.
  930. This option changes get_user() and friends to use the 'unprivileged'
  931. variant of the load/store instructions. This ensures that user-space
  932. really did have access to the supplied memory. When addr_limit is
  933. set to kernel memory the UAO bit will be set, allowing privileged
  934. access to kernel memory.
  935. Choosing this option will cause copy_to_user() et al to use user-space
  936. memory permissions.
  937. The feature is detected at runtime, the kernel will use the
  938. regular load/store instructions if the cpu does not implement the
  939. feature.
  940. config ARM64_PMEM
  941. bool "Enable support for persistent memory"
  942. select ARCH_HAS_PMEM_API
  943. select ARCH_HAS_UACCESS_FLUSHCACHE
  944. help
  945. Say Y to enable support for the persistent memory API based on the
  946. ARMv8.2 DCPoP feature.
  947. The feature is detected at runtime, and the kernel will use DC CVAC
  948. operations if DC CVAP is not supported (following the behaviour of
  949. DC CVAP itself if the system does not define a point of persistence).
  950. config ARM64_RAS_EXTN
  951. bool "Enable support for RAS CPU Extensions"
  952. default y
  953. help
  954. CPUs that support the Reliability, Availability and Serviceability
  955. (RAS) Extensions, part of ARMv8.2 are able to track faults and
  956. errors, classify them and report them to software.
  957. On CPUs with these extensions system software can use additional
  958. barriers to determine if faults are pending and read the
  959. classification from a new set of registers.
  960. Selecting this feature will allow the kernel to use these barriers
  961. and access the new registers if the system supports the extension.
  962. Platform RAS features may additionally depend on firmware support.
  963. endmenu
  964. config ARM64_SVE
  965. bool "ARM Scalable Vector Extension support"
  966. default y
  967. depends on !KVM || ARM64_VHE
  968. help
  969. The Scalable Vector Extension (SVE) is an extension to the AArch64
  970. execution state which complements and extends the SIMD functionality
  971. of the base architecture to support much larger vectors and to enable
  972. additional vectorisation opportunities.
  973. To enable use of this extension on CPUs that implement it, say Y.
  974. Note that for architectural reasons, firmware _must_ implement SVE
  975. support when running on SVE capable hardware. The required support
  976. is present in:
  977. * version 1.5 and later of the ARM Trusted Firmware
  978. * the AArch64 boot wrapper since commit 5e1261e08abf
  979. ("bootwrapper: SVE: Enable SVE for EL2 and below").
  980. For other firmware implementations, consult the firmware documentation
  981. or vendor.
  982. If you need the kernel to boot on SVE-capable hardware with broken
  983. firmware, you may need to say N here until you get your firmware
  984. fixed. Otherwise, you may experience firmware panics or lockups when
  985. booting the kernel. If unsure and you are not observing these
  986. symptoms, you should assume that it is safe to say Y.
  987. CPUs that support SVE are architecturally required to support the
  988. Virtualization Host Extensions (VHE), so the kernel makes no
  989. provision for supporting SVE alongside KVM without VHE enabled.
  990. Thus, you will need to enable CONFIG_ARM64_VHE if you want to support
  991. KVM in the same kernel image.
  992. config ARM64_MODULE_PLTS
  993. bool
  994. select HAVE_MOD_ARCH_SPECIFIC
  995. config RELOCATABLE
  996. bool
  997. help
  998. This builds the kernel as a Position Independent Executable (PIE),
  999. which retains all relocation metadata required to relocate the
  1000. kernel binary at runtime to a different virtual address than the
  1001. address it was linked at.
  1002. Since AArch64 uses the RELA relocation format, this requires a
  1003. relocation pass at runtime even if the kernel is loaded at the
  1004. same address it was linked at.
  1005. config RANDOMIZE_BASE
  1006. bool "Randomize the address of the kernel image"
  1007. select ARM64_MODULE_PLTS if MODULES
  1008. select RELOCATABLE
  1009. help
  1010. Randomizes the virtual address at which the kernel image is
  1011. loaded, as a security feature that deters exploit attempts
  1012. relying on knowledge of the location of kernel internals.
  1013. It is the bootloader's job to provide entropy, by passing a
  1014. random u64 value in /chosen/kaslr-seed at kernel entry.
  1015. When booting via the UEFI stub, it will invoke the firmware's
  1016. EFI_RNG_PROTOCOL implementation (if available) to supply entropy
  1017. to the kernel proper. In addition, it will randomise the physical
  1018. location of the kernel Image as well.
  1019. If unsure, say N.
  1020. config RANDOMIZE_MODULE_REGION_FULL
  1021. bool "Randomize the module region over a 4 GB range"
  1022. depends on RANDOMIZE_BASE
  1023. default y
  1024. help
  1025. Randomizes the location of the module region inside a 4 GB window
  1026. covering the core kernel. This way, it is less likely for modules
  1027. to leak information about the location of core kernel data structures
  1028. but it does imply that function calls between modules and the core
  1029. kernel will need to be resolved via veneers in the module PLT.
  1030. When this option is not set, the module region will be randomized over
  1031. a limited range that contains the [_stext, _etext] interval of the
  1032. core kernel, so branch relocations are always in range.
  1033. endmenu
  1034. menu "Boot options"
  1035. config ARM64_ACPI_PARKING_PROTOCOL
  1036. bool "Enable support for the ARM64 ACPI parking protocol"
  1037. depends on ACPI
  1038. help
  1039. Enable support for the ARM64 ACPI parking protocol. If disabled
  1040. the kernel will not allow booting through the ARM64 ACPI parking
  1041. protocol even if the corresponding data is present in the ACPI
  1042. MADT table.
  1043. config CMDLINE
  1044. string "Default kernel command string"
  1045. default ""
  1046. help
  1047. Provide a set of default command-line options at build time by
  1048. entering them here. As a minimum, you should specify the the
  1049. root device (e.g. root=/dev/nfs).
  1050. config CMDLINE_FORCE
  1051. bool "Always use the default kernel command string"
  1052. help
  1053. Always use the default kernel command string, even if the boot
  1054. loader passes other arguments to the kernel.
  1055. This is useful if you cannot or don't want to change the
  1056. command-line options your boot loader passes to the kernel.
  1057. config EFI_STUB
  1058. bool
  1059. config EFI
  1060. bool "UEFI runtime support"
  1061. depends on OF && !CPU_BIG_ENDIAN
  1062. depends on KERNEL_MODE_NEON
  1063. select ARCH_SUPPORTS_ACPI
  1064. select LIBFDT
  1065. select UCS2_STRING
  1066. select EFI_PARAMS_FROM_FDT
  1067. select EFI_RUNTIME_WRAPPERS
  1068. select EFI_STUB
  1069. select EFI_ARMSTUB
  1070. default y
  1071. help
  1072. This option provides support for runtime services provided
  1073. by UEFI firmware (such as non-volatile variables, realtime
  1074. clock, and platform reset). A UEFI stub is also provided to
  1075. allow the kernel to be booted as an EFI application. This
  1076. is only useful on systems that have UEFI firmware.
  1077. config DMI
  1078. bool "Enable support for SMBIOS (DMI) tables"
  1079. depends on EFI
  1080. default y
  1081. help
  1082. This enables SMBIOS/DMI feature for systems.
  1083. This option is only useful on systems that have UEFI firmware.
  1084. However, even with this option, the resultant kernel should
  1085. continue to boot on existing non-UEFI platforms.
  1086. endmenu
  1087. config COMPAT
  1088. bool "Kernel support for 32-bit EL0"
  1089. depends on ARM64_4K_PAGES || EXPERT
  1090. select COMPAT_BINFMT_ELF if BINFMT_ELF
  1091. select HAVE_UID16
  1092. select OLD_SIGSUSPEND3
  1093. select COMPAT_OLD_SIGACTION
  1094. help
  1095. This option enables support for a 32-bit EL0 running under a 64-bit
  1096. kernel at EL1. AArch32-specific components such as system calls,
  1097. the user helper functions, VFP support and the ptrace interface are
  1098. handled appropriately by the kernel.
  1099. If you use a page size other than 4KB (i.e, 16KB or 64KB), please be aware
  1100. that you will only be able to execute AArch32 binaries that were compiled
  1101. with page size aligned segments.
  1102. If you want to execute 32-bit userspace applications, say Y.
  1103. config SYSVIPC_COMPAT
  1104. def_bool y
  1105. depends on COMPAT && SYSVIPC
  1106. menu "Power management options"
  1107. source "kernel/power/Kconfig"
  1108. config ARCH_HIBERNATION_POSSIBLE
  1109. def_bool y
  1110. depends on CPU_PM
  1111. config ARCH_HIBERNATION_HEADER
  1112. def_bool y
  1113. depends on HIBERNATION
  1114. config ARCH_SUSPEND_POSSIBLE
  1115. def_bool y
  1116. endmenu
  1117. menu "CPU Power Management"
  1118. source "drivers/cpuidle/Kconfig"
  1119. source "drivers/cpufreq/Kconfig"
  1120. endmenu
  1121. source "drivers/firmware/Kconfig"
  1122. source "drivers/acpi/Kconfig"
  1123. source "arch/arm64/kvm/Kconfig"
  1124. if CRYPTO
  1125. source "arch/arm64/crypto/Kconfig"
  1126. endif