1# SPDX-License-Identifier: GPL-2.0-only 2# 3# Library configuration 4# 5 6config BINARY_PRINTF 7 def_bool n 8 9menu "Library routines" 10 11config RAID6_PQ 12 tristate 13 14config RAID6_PQ_BENCHMARK 15 bool "Automatically choose fastest RAID6 PQ functions" 16 depends on RAID6_PQ 17 default y 18 help 19 Benchmark all available RAID6 PQ functions on init and choose the 20 fastest one. 21 22config LINEAR_RANGES 23 tristate 24 25config PACKING 26 bool "Generic bitfield packing and unpacking" 27 select BITREVERSE 28 default n 29 help 30 This option provides the packing() helper function, which permits 31 converting bitfields between a CPU-usable representation and a 32 memory representation that can have any combination of these quirks: 33 - Is little endian (bytes are reversed within a 32-bit group) 34 - The least-significant 32-bit word comes first (within a 64-bit 35 group) 36 - The most significant bit of a byte is at its right (bit 0 of a 37 register description is numerically 2^7). 38 Drivers may use these helpers to match the bit indices as described 39 in the data sheets of the peripherals they are in control of. 40 41 When in doubt, say N. 42 43config PACKING_KUNIT_TEST 44 tristate "KUnit tests for packing library" if !KUNIT_ALL_TESTS 45 depends on PACKING && KUNIT 46 default KUNIT_ALL_TESTS 47 help 48 This builds KUnit tests for the packing library. 49 50 For more information on KUnit and unit tests in general, 51 please refer to the KUnit documentation in Documentation/dev-tools/kunit/. 52 53 When in doubt, say N. 54 55config BITREVERSE 56 tristate 57 58config HAVE_ARCH_BITREVERSE 59 bool 60 default n 61 help 62 This option enables the use of hardware bit-reversal instructions on 63 architectures which support such operations. 64 65config ARCH_HAS_STRNCPY_FROM_USER 66 bool 67 68config ARCH_HAS_STRNLEN_USER 69 bool 70 71config GENERIC_STRNCPY_FROM_USER 72 def_bool !ARCH_HAS_STRNCPY_FROM_USER 73 74config GENERIC_STRNLEN_USER 75 def_bool !ARCH_HAS_STRNLEN_USER 76 77config GENERIC_NET_UTILS 78 bool 79 80source "lib/math/Kconfig" 81 82config NO_GENERIC_PCI_IOPORT_MAP 83 bool 84 85config GENERIC_IOMAP 86 bool 87 select GENERIC_PCI_IOMAP 88 89config STMP_DEVICE 90 bool 91 92config ARCH_USE_CMPXCHG_LOCKREF 93 bool 94 95config ARCH_HAS_FAST_MULTIPLIER 96 bool 97 98config ARCH_USE_SYM_ANNOTATIONS 99 bool 100 101config INDIRECT_PIO 102 bool "Access I/O in non-MMIO mode" 103 depends on ARM64 104 depends on HAS_IOPORT 105 help 106 On some platforms where no separate I/O space exists, there are I/O 107 hosts which can not be accessed in MMIO mode. Using the logical PIO 108 mechanism, the host-local I/O resource can be mapped into system 109 logic PIO space shared with MMIO hosts, such as PCI/PCIe, then the 110 system can access the I/O devices with the mapped-logic PIO through 111 I/O accessors. 112 113 This way has relatively little I/O performance cost. Please make 114 sure your devices really need this configure item enabled. 115 116 When in doubt, say N. 117 118config INDIRECT_IOMEM 119 bool 120 help 121 This is selected by other options/architectures to provide the 122 emulated iomem accessors. 123 124config INDIRECT_IOMEM_FALLBACK 125 bool 126 depends on INDIRECT_IOMEM 127 help 128 If INDIRECT_IOMEM is selected, this enables falling back to plain 129 mmio accesses when the IO memory address is not a registered 130 emulated region. 131 132config TRACE_MMIO_ACCESS 133 bool "Register read/write tracing" 134 depends on TRACING && ARCH_HAVE_TRACE_MMIO_ACCESS 135 help 136 Create tracepoints for MMIO read/write operations. These trace events 137 can be used for logging all MMIO read/write operations. 138 139source "lib/crypto/Kconfig" 140 141config CRC_CCITT 142 tristate 143 144config CRC16 145 tristate 146 147config CRC_T10DIF 148 tristate "CRC calculation for the T10 Data Integrity Field" 149 help 150 This option is only needed if a module that's not in the 151 kernel tree needs to calculate CRC checks for use with the 152 SCSI data integrity subsystem. 153 154config ARCH_HAS_CRC_T10DIF 155 bool 156 157config CRC_T10DIF_ARCH 158 tristate 159 default CRC_T10DIF if ARCH_HAS_CRC_T10DIF && CRC_OPTIMIZATIONS 160 161config CRC_ITU_T 162 tristate "CRC ITU-T V.41 functions" 163 help 164 This option is provided for the case where no in-kernel-tree 165 modules require CRC ITU-T V.41 functions, but a module built outside 166 the kernel tree does. Such modules that use library CRC ITU-T V.41 167 functions require M here. 168 169config CRC32 170 tristate 171 select BITREVERSE 172 173config ARCH_HAS_CRC32 174 bool 175 176config CRC32_ARCH 177 tristate 178 default CRC32 if ARCH_HAS_CRC32 && CRC_OPTIMIZATIONS 179 180config CRC64 181 tristate 182 183config ARCH_HAS_CRC64 184 bool 185 186config CRC64_ARCH 187 tristate 188 default CRC64 if ARCH_HAS_CRC64 && CRC_OPTIMIZATIONS 189 190config CRC4 191 tristate 192 193config CRC7 194 tristate 195 196config LIBCRC32C 197 tristate 198 select CRC32 199 help 200 This option just selects CRC32 and is provided for compatibility 201 purposes until the users are updated to select CRC32 directly. 202 203config CRC8 204 tristate 205 206config CRC_OPTIMIZATIONS 207 bool "Enable optimized CRC implementations" if EXPERT 208 default y 209 help 210 Disabling this option reduces code size slightly by disabling the 211 architecture-optimized implementations of any CRC variants that are 212 enabled. CRC checksumming performance may get much slower. 213 214 Keep this enabled unless you're really trying to minimize the size of 215 the kernel. 216 217config XXHASH 218 tristate 219 220config AUDIT_GENERIC 221 bool 222 depends on AUDIT && !AUDIT_ARCH 223 default y 224 225config AUDIT_ARCH_COMPAT_GENERIC 226 bool 227 default n 228 229config AUDIT_COMPAT_GENERIC 230 bool 231 depends on AUDIT_GENERIC && AUDIT_ARCH_COMPAT_GENERIC && COMPAT 232 default y 233 234config RANDOM32_SELFTEST 235 bool "PRNG perform self test on init" 236 help 237 This option enables the 32 bit PRNG library functions to perform a 238 self test on initialization. 239 240# 241# compression support is select'ed if needed 242# 243config 842_COMPRESS 244 select CRC32 245 tristate 246 247config 842_DECOMPRESS 248 select CRC32 249 tristate 250 251config ZLIB_INFLATE 252 tristate 253 254config ZLIB_DEFLATE 255 tristate 256 select BITREVERSE 257 258config ZLIB_DFLTCC 259 def_bool y 260 depends on S390 261 prompt "Enable s390x DEFLATE CONVERSION CALL support for kernel zlib" 262 help 263 Enable s390x hardware support for zlib in the kernel. 264 265config LZO_COMPRESS 266 tristate 267 268config LZO_DECOMPRESS 269 tristate 270 271config LZ4_COMPRESS 272 tristate 273 274config LZ4HC_COMPRESS 275 tristate 276 277config LZ4_DECOMPRESS 278 tristate 279 280config ZSTD_COMMON 281 select XXHASH 282 tristate 283 284config ZSTD_COMPRESS 285 select ZSTD_COMMON 286 tristate 287 288config ZSTD_DECOMPRESS 289 select ZSTD_COMMON 290 tristate 291 292source "lib/xz/Kconfig" 293 294# 295# These all provide a common interface (hence the apparent duplication with 296# ZLIB_INFLATE; DECOMPRESS_GZIP is just a wrapper.) 297# 298config DECOMPRESS_GZIP 299 select ZLIB_INFLATE 300 tristate 301 302config DECOMPRESS_BZIP2 303 tristate 304 305config DECOMPRESS_LZMA 306 tristate 307 308config DECOMPRESS_XZ 309 select XZ_DEC 310 tristate 311 312config DECOMPRESS_LZO 313 select LZO_DECOMPRESS 314 tristate 315 316config DECOMPRESS_LZ4 317 select LZ4_DECOMPRESS 318 tristate 319 320config DECOMPRESS_ZSTD 321 select ZSTD_DECOMPRESS 322 tristate 323 324# 325# Generic allocator support is selected if needed 326# 327config GENERIC_ALLOCATOR 328 bool 329 330# 331# reed solomon support is select'ed if needed 332# 333config REED_SOLOMON 334 tristate 335 336config REED_SOLOMON_ENC8 337 bool 338 339config REED_SOLOMON_DEC8 340 bool 341 342config REED_SOLOMON_ENC16 343 bool 344 345config REED_SOLOMON_DEC16 346 bool 347 348# 349# BCH support is selected if needed 350# 351config BCH 352 tristate 353 select BITREVERSE 354 355config BCH_CONST_PARAMS 356 bool 357 help 358 Drivers may select this option to force specific constant 359 values for parameters 'm' (Galois field order) and 't' 360 (error correction capability). Those specific values must 361 be set by declaring default values for symbols BCH_CONST_M 362 and BCH_CONST_T. 363 Doing so will enable extra compiler optimizations, 364 improving encoding and decoding performance up to 2x for 365 usual (m,t) values (typically such that m*t < 200). 366 When this option is selected, the BCH library supports 367 only a single (m,t) configuration. This is mainly useful 368 for NAND flash board drivers requiring known, fixed BCH 369 parameters. 370 371config BCH_CONST_M 372 int 373 range 5 15 374 help 375 Constant value for Galois field order 'm'. If 'k' is the 376 number of data bits to protect, 'm' should be chosen such 377 that (k + m*t) <= 2**m - 1. 378 Drivers should declare a default value for this symbol if 379 they select option BCH_CONST_PARAMS. 380 381config BCH_CONST_T 382 int 383 help 384 Constant value for error correction capability in bits 't'. 385 Drivers should declare a default value for this symbol if 386 they select option BCH_CONST_PARAMS. 387 388# 389# Textsearch support is select'ed if needed 390# 391config TEXTSEARCH 392 bool 393 394config TEXTSEARCH_KMP 395 tristate 396 397config TEXTSEARCH_BM 398 tristate 399 400config TEXTSEARCH_FSM 401 tristate 402 403config BTREE 404 bool 405 406config INTERVAL_TREE 407 bool 408 help 409 Simple, embeddable, interval-tree. Can find the start of an 410 overlapping range in log(n) time and then iterate over all 411 overlapping nodes. The algorithm is implemented as an 412 augmented rbtree. 413 414 See: 415 416 Documentation/core-api/rbtree.rst 417 418 for more information. 419 420config INTERVAL_TREE_SPAN_ITER 421 bool 422 depends on INTERVAL_TREE 423 424config XARRAY_MULTI 425 bool 426 help 427 Support entries which occupy multiple consecutive indices in the 428 XArray. 429 430config ASSOCIATIVE_ARRAY 431 bool 432 help 433 Generic associative array. Can be searched and iterated over whilst 434 it is being modified. It is also reasonably quick to search and 435 modify. The algorithms are non-recursive, and the trees are highly 436 capacious. 437 438 See: 439 440 Documentation/core-api/assoc_array.rst 441 442 for more information. 443 444config CLOSURES 445 bool 446 447config HAS_IOMEM 448 bool 449 depends on !NO_IOMEM 450 default y 451 452config HAS_IOPORT 453 bool 454 455config HAS_IOPORT_MAP 456 bool 457 depends on HAS_IOMEM && !NO_IOPORT_MAP 458 default y 459 460source "kernel/dma/Kconfig" 461 462config SGL_ALLOC 463 bool 464 default n 465 466config IOMMU_HELPER 467 bool 468 469config CHECK_SIGNATURE 470 bool 471 472config CPUMASK_OFFSTACK 473 bool "Force CPU masks off stack" if DEBUG_PER_CPU_MAPS 474 help 475 Use dynamic allocation for cpumask_var_t, instead of putting 476 them on the stack. This is a bit more expensive, but avoids 477 stack overflow. 478 479config FORCE_NR_CPUS 480 def_bool !SMP 481 482config CPU_RMAP 483 bool 484 depends on SMP 485 486config DQL 487 bool 488 489config GLOB 490 bool 491# This actually supports modular compilation, but the module overhead 492# is ridiculous for the amount of code involved. Until an out-of-tree 493# driver asks for it, we'll just link it directly it into the kernel 494# when required. Since we're ignoring out-of-tree users, there's also 495# no need bother prompting for a manual decision: 496# prompt "glob_match() function" 497 help 498 This option provides a glob_match function for performing 499 simple text pattern matching. It originated in the ATA code 500 to blacklist particular drive models, but other device drivers 501 may need similar functionality. 502 503 All drivers in the Linux kernel tree that require this function 504 should automatically select this option. Say N unless you 505 are compiling an out-of tree driver which tells you that it 506 depends on this. 507 508config GLOB_SELFTEST 509 tristate "glob self-test on init" 510 depends on GLOB 511 help 512 This option enables a simple self-test of the glob_match 513 function on startup. It is primarily useful for people 514 working on the code to ensure they haven't introduced any 515 regressions. 516 517 It only adds a little bit of code and slows kernel boot (or 518 module load) by a small amount, so you're welcome to play with 519 it, but you probably don't need it. 520 521# 522# Netlink attribute parsing support is select'ed if needed 523# 524config NLATTR 525 bool 526 527# 528# Generic 64-bit atomic support is selected if needed 529# 530config GENERIC_ATOMIC64 531 bool 532 533config LRU_CACHE 534 tristate 535 536config CLZ_TAB 537 bool 538 539config IRQ_POLL 540 bool "IRQ polling library" 541 help 542 Helper library to poll interrupt mitigation using polling. 543 544config MPILIB 545 tristate 546 select CLZ_TAB 547 help 548 Multiprecision maths library from GnuPG. 549 It is used to implement RSA digital signature verification, 550 which is used by IMA/EVM digital signature extension. 551 552config SIGNATURE 553 tristate 554 depends on KEYS 555 select CRYPTO 556 select CRYPTO_SHA1 557 select MPILIB 558 help 559 Digital signature verification. Currently only RSA is supported. 560 Implementation is done using GnuPG MPI library 561 562config DIMLIB 563 tristate 564 depends on NET 565 help 566 Dynamic Interrupt Moderation library. 567 Implements an algorithm for dynamically changing CQ moderation values 568 according to run time performance. 569 570# 571# libfdt files, only selected if needed. 572# 573config LIBFDT 574 bool 575 576config OID_REGISTRY 577 tristate 578 help 579 Enable fast lookup object identifier registry. 580 581config UCS2_STRING 582 tristate 583 584# 585# generic vdso 586# 587source "lib/vdso/Kconfig" 588 589source "lib/fonts/Kconfig" 590 591config SG_SPLIT 592 def_bool n 593 help 594 Provides a helper to split scatterlists into chunks, each chunk being 595 a scatterlist. This should be selected by a driver or an API which 596 whishes to split a scatterlist amongst multiple DMA channels. 597 598config SG_POOL 599 def_bool n 600 help 601 Provides a helper to allocate chained scatterlists. This should be 602 selected by a driver or an API which whishes to allocate chained 603 scatterlist. 604 605# 606# sg chaining option 607# 608 609config ARCH_NO_SG_CHAIN 610 def_bool n 611 612config ARCH_HAS_PMEM_API 613 bool 614 615config MEMREGION 616 bool 617 618config ARCH_HAS_CPU_CACHE_INVALIDATE_MEMREGION 619 bool 620 621config ARCH_HAS_MEMREMAP_COMPAT_ALIGN 622 bool 623 624# use memcpy to implement user copies for nommu architectures 625config UACCESS_MEMCPY 626 bool 627 628config ARCH_HAS_UACCESS_FLUSHCACHE 629 bool 630 631# arch has a concept of a recoverable synchronous exception due to a 632# memory-read error like x86 machine-check or ARM data-abort, and 633# implements copy_mc_to_{user,kernel} to abort and report 634# 'bytes-transferred' if that exception fires when accessing the source 635# buffer. 636config ARCH_HAS_COPY_MC 637 bool 638 639# Temporary. Goes away when all archs are cleaned up 640config ARCH_STACKWALK 641 bool 642 643config STACKDEPOT 644 bool 645 select STACKTRACE 646 help 647 Stack depot: stack trace storage that avoids duplication 648 649config STACKDEPOT_ALWAYS_INIT 650 bool 651 select STACKDEPOT 652 help 653 Always initialize stack depot during early boot 654 655config STACKDEPOT_MAX_FRAMES 656 int "Maximum number of frames in trace saved in stack depot" 657 range 1 256 658 default 64 659 depends on STACKDEPOT 660 661config REF_TRACKER 662 bool 663 depends on STACKTRACE_SUPPORT 664 select STACKDEPOT 665 666config SBITMAP 667 bool 668 669config PARMAN 670 tristate "parman" if COMPILE_TEST 671 672config OBJAGG 673 tristate "objagg" if COMPILE_TEST 674 675config LWQ_TEST 676 bool "Boot-time test for lwq queuing" 677 help 678 Run boot-time test of light-weight queuing. 679 680endmenu 681 682config GENERIC_IOREMAP 683 bool 684 685config GENERIC_LIB_ASHLDI3 686 bool 687 688config GENERIC_LIB_ASHRDI3 689 bool 690 691config GENERIC_LIB_LSHRDI3 692 bool 693 694config GENERIC_LIB_MULDI3 695 bool 696 697config GENERIC_LIB_CMPDI2 698 bool 699 700config GENERIC_LIB_UCMPDI2 701 bool 702 703config GENERIC_LIB_DEVMEM_IS_ALLOWED 704 bool 705 706config PLDMFW 707 bool 708 default n 709 710config ASN1_ENCODER 711 tristate 712 713config POLYNOMIAL 714 tristate 715 716config FIRMWARE_TABLE 717 bool 718 719config UNION_FIND 720 bool 721 722config MIN_HEAP 723 bool 724