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 "CRC-CCITT functions" 143 help 144 This option is provided for the case where no in-kernel-tree 145 modules require CRC-CCITT functions, but a module built outside 146 the kernel tree does. Such modules that use library CRC-CCITT 147 functions require M here. 148 149config CRC16 150 tristate "CRC16 functions" 151 help 152 This option is provided for the case where no in-kernel-tree 153 modules require CRC16 functions, but a module built outside 154 the kernel tree does. Such modules that use library CRC16 155 functions require M here. 156 157config CRC_T10DIF 158 tristate "CRC calculation for the T10 Data Integrity Field" 159 help 160 This option is only needed if a module that's not in the 161 kernel tree needs to calculate CRC checks for use with the 162 SCSI data integrity subsystem. 163 164config ARCH_HAS_CRC_T10DIF 165 bool 166 167config CRC_T10DIF_ARCH 168 tristate 169 default CRC_T10DIF if ARCH_HAS_CRC_T10DIF && CRC_OPTIMIZATIONS 170 171config CRC_ITU_T 172 tristate "CRC ITU-T V.41 functions" 173 help 174 This option is provided for the case where no in-kernel-tree 175 modules require CRC ITU-T V.41 functions, but a module built outside 176 the kernel tree does. Such modules that use library CRC ITU-T V.41 177 functions require M here. 178 179config CRC32 180 tristate "CRC32/CRC32c functions" 181 default y 182 select BITREVERSE 183 help 184 This option is provided for the case where no in-kernel-tree 185 modules require CRC32/CRC32c functions, but a module built outside 186 the kernel tree does. Such modules that use library CRC32/CRC32c 187 functions require M here. 188 189config ARCH_HAS_CRC32 190 bool 191 192config CRC32_ARCH 193 tristate 194 default CRC32 if ARCH_HAS_CRC32 && CRC_OPTIMIZATIONS 195 196config CRC64 197 tristate "CRC64 functions" 198 help 199 This option is provided for the case where no in-kernel-tree 200 modules require CRC64 functions, but a module built outside 201 the kernel tree does. Such modules that use library CRC64 202 functions require M here. 203 204config ARCH_HAS_CRC64 205 bool 206 207config CRC64_ARCH 208 tristate 209 default CRC64 if ARCH_HAS_CRC64 && CRC_OPTIMIZATIONS 210 211config CRC4 212 tristate 213 214config CRC7 215 tristate "CRC7 functions" 216 help 217 This option is provided for the case where no in-kernel-tree 218 modules require CRC7 functions, but a module built outside 219 the kernel tree does. Such modules that use library CRC7 220 functions require M here. 221 222config LIBCRC32C 223 tristate "CRC32c (Castagnoli, et al) Cyclic Redundancy-Check" 224 select CRC32 225 help 226 This option just selects CRC32 and is provided for compatibility 227 purposes until the users are updated to select CRC32 directly. 228 229config CRC8 230 tristate "CRC8 function" 231 help 232 This option provides CRC8 function. Drivers may select this 233 when they need to do cyclic redundancy check according CRC8 234 algorithm. Module will be called crc8. 235 236config CRC_OPTIMIZATIONS 237 bool "Enable optimized CRC implementations" if EXPERT 238 default y 239 help 240 Disabling this option reduces code size slightly by disabling the 241 architecture-optimized implementations of any CRC variants that are 242 enabled. CRC checksumming performance may get much slower. 243 244 Keep this enabled unless you're really trying to minimize the size of 245 the kernel. 246 247config XXHASH 248 tristate 249 250config AUDIT_GENERIC 251 bool 252 depends on AUDIT && !AUDIT_ARCH 253 default y 254 255config AUDIT_ARCH_COMPAT_GENERIC 256 bool 257 default n 258 259config AUDIT_COMPAT_GENERIC 260 bool 261 depends on AUDIT_GENERIC && AUDIT_ARCH_COMPAT_GENERIC && COMPAT 262 default y 263 264config RANDOM32_SELFTEST 265 bool "PRNG perform self test on init" 266 help 267 This option enables the 32 bit PRNG library functions to perform a 268 self test on initialization. 269 270# 271# compression support is select'ed if needed 272# 273config 842_COMPRESS 274 select CRC32 275 tristate 276 277config 842_DECOMPRESS 278 select CRC32 279 tristate 280 281config ZLIB_INFLATE 282 tristate 283 284config ZLIB_DEFLATE 285 tristate 286 select BITREVERSE 287 288config ZLIB_DFLTCC 289 def_bool y 290 depends on S390 291 prompt "Enable s390x DEFLATE CONVERSION CALL support for kernel zlib" 292 help 293 Enable s390x hardware support for zlib in the kernel. 294 295config LZO_COMPRESS 296 tristate 297 298config LZO_DECOMPRESS 299 tristate 300 301config LZ4_COMPRESS 302 tristate 303 304config LZ4HC_COMPRESS 305 tristate 306 307config LZ4_DECOMPRESS 308 tristate 309 310config ZSTD_COMMON 311 select XXHASH 312 tristate 313 314config ZSTD_COMPRESS 315 select ZSTD_COMMON 316 tristate 317 318config ZSTD_DECOMPRESS 319 select ZSTD_COMMON 320 tristate 321 322source "lib/xz/Kconfig" 323 324# 325# These all provide a common interface (hence the apparent duplication with 326# ZLIB_INFLATE; DECOMPRESS_GZIP is just a wrapper.) 327# 328config DECOMPRESS_GZIP 329 select ZLIB_INFLATE 330 tristate 331 332config DECOMPRESS_BZIP2 333 tristate 334 335config DECOMPRESS_LZMA 336 tristate 337 338config DECOMPRESS_XZ 339 select XZ_DEC 340 tristate 341 342config DECOMPRESS_LZO 343 select LZO_DECOMPRESS 344 tristate 345 346config DECOMPRESS_LZ4 347 select LZ4_DECOMPRESS 348 tristate 349 350config DECOMPRESS_ZSTD 351 select ZSTD_DECOMPRESS 352 tristate 353 354# 355# Generic allocator support is selected if needed 356# 357config GENERIC_ALLOCATOR 358 bool 359 360# 361# reed solomon support is select'ed if needed 362# 363config REED_SOLOMON 364 tristate 365 366config REED_SOLOMON_ENC8 367 bool 368 369config REED_SOLOMON_DEC8 370 bool 371 372config REED_SOLOMON_ENC16 373 bool 374 375config REED_SOLOMON_DEC16 376 bool 377 378# 379# BCH support is selected if needed 380# 381config BCH 382 tristate 383 select BITREVERSE 384 385config BCH_CONST_PARAMS 386 bool 387 help 388 Drivers may select this option to force specific constant 389 values for parameters 'm' (Galois field order) and 't' 390 (error correction capability). Those specific values must 391 be set by declaring default values for symbols BCH_CONST_M 392 and BCH_CONST_T. 393 Doing so will enable extra compiler optimizations, 394 improving encoding and decoding performance up to 2x for 395 usual (m,t) values (typically such that m*t < 200). 396 When this option is selected, the BCH library supports 397 only a single (m,t) configuration. This is mainly useful 398 for NAND flash board drivers requiring known, fixed BCH 399 parameters. 400 401config BCH_CONST_M 402 int 403 range 5 15 404 help 405 Constant value for Galois field order 'm'. If 'k' is the 406 number of data bits to protect, 'm' should be chosen such 407 that (k + m*t) <= 2**m - 1. 408 Drivers should declare a default value for this symbol if 409 they select option BCH_CONST_PARAMS. 410 411config BCH_CONST_T 412 int 413 help 414 Constant value for error correction capability in bits 't'. 415 Drivers should declare a default value for this symbol if 416 they select option BCH_CONST_PARAMS. 417 418# 419# Textsearch support is select'ed if needed 420# 421config TEXTSEARCH 422 bool 423 424config TEXTSEARCH_KMP 425 tristate 426 427config TEXTSEARCH_BM 428 tristate 429 430config TEXTSEARCH_FSM 431 tristate 432 433config BTREE 434 bool 435 436config INTERVAL_TREE 437 bool 438 help 439 Simple, embeddable, interval-tree. Can find the start of an 440 overlapping range in log(n) time and then iterate over all 441 overlapping nodes. The algorithm is implemented as an 442 augmented rbtree. 443 444 See: 445 446 Documentation/core-api/rbtree.rst 447 448 for more information. 449 450config INTERVAL_TREE_SPAN_ITER 451 bool 452 depends on INTERVAL_TREE 453 454config XARRAY_MULTI 455 bool 456 help 457 Support entries which occupy multiple consecutive indices in the 458 XArray. 459 460config ASSOCIATIVE_ARRAY 461 bool 462 help 463 Generic associative array. Can be searched and iterated over whilst 464 it is being modified. It is also reasonably quick to search and 465 modify. The algorithms are non-recursive, and the trees are highly 466 capacious. 467 468 See: 469 470 Documentation/core-api/assoc_array.rst 471 472 for more information. 473 474config CLOSURES 475 bool 476 477config HAS_IOMEM 478 bool 479 depends on !NO_IOMEM 480 default y 481 482config HAS_IOPORT 483 bool 484 485config HAS_IOPORT_MAP 486 bool 487 depends on HAS_IOMEM && !NO_IOPORT_MAP 488 default y 489 490source "kernel/dma/Kconfig" 491 492config SGL_ALLOC 493 bool 494 default n 495 496config IOMMU_HELPER 497 bool 498 499config CHECK_SIGNATURE 500 bool 501 502config CPUMASK_OFFSTACK 503 bool "Force CPU masks off stack" if DEBUG_PER_CPU_MAPS 504 help 505 Use dynamic allocation for cpumask_var_t, instead of putting 506 them on the stack. This is a bit more expensive, but avoids 507 stack overflow. 508 509config FORCE_NR_CPUS 510 def_bool !SMP 511 512config CPU_RMAP 513 bool 514 depends on SMP 515 516config DQL 517 bool 518 519config GLOB 520 bool 521# This actually supports modular compilation, but the module overhead 522# is ridiculous for the amount of code involved. Until an out-of-tree 523# driver asks for it, we'll just link it directly it into the kernel 524# when required. Since we're ignoring out-of-tree users, there's also 525# no need bother prompting for a manual decision: 526# prompt "glob_match() function" 527 help 528 This option provides a glob_match function for performing 529 simple text pattern matching. It originated in the ATA code 530 to blacklist particular drive models, but other device drivers 531 may need similar functionality. 532 533 All drivers in the Linux kernel tree that require this function 534 should automatically select this option. Say N unless you 535 are compiling an out-of tree driver which tells you that it 536 depends on this. 537 538config GLOB_SELFTEST 539 tristate "glob self-test on init" 540 depends on GLOB 541 help 542 This option enables a simple self-test of the glob_match 543 function on startup. It is primarily useful for people 544 working on the code to ensure they haven't introduced any 545 regressions. 546 547 It only adds a little bit of code and slows kernel boot (or 548 module load) by a small amount, so you're welcome to play with 549 it, but you probably don't need it. 550 551# 552# Netlink attribute parsing support is select'ed if needed 553# 554config NLATTR 555 bool 556 557# 558# Generic 64-bit atomic support is selected if needed 559# 560config GENERIC_ATOMIC64 561 bool 562 563config LRU_CACHE 564 tristate 565 566config CLZ_TAB 567 bool 568 569config IRQ_POLL 570 bool "IRQ polling library" 571 help 572 Helper library to poll interrupt mitigation using polling. 573 574config MPILIB 575 tristate 576 select CLZ_TAB 577 help 578 Multiprecision maths library from GnuPG. 579 It is used to implement RSA digital signature verification, 580 which is used by IMA/EVM digital signature extension. 581 582config SIGNATURE 583 tristate 584 depends on KEYS 585 select CRYPTO 586 select CRYPTO_SHA1 587 select MPILIB 588 help 589 Digital signature verification. Currently only RSA is supported. 590 Implementation is done using GnuPG MPI library 591 592config DIMLIB 593 tristate 594 depends on NET 595 help 596 Dynamic Interrupt Moderation library. 597 Implements an algorithm for dynamically changing CQ moderation values 598 according to run time performance. 599 600# 601# libfdt files, only selected if needed. 602# 603config LIBFDT 604 bool 605 606config OID_REGISTRY 607 tristate 608 help 609 Enable fast lookup object identifier registry. 610 611config UCS2_STRING 612 tristate 613 614# 615# generic vdso 616# 617source "lib/vdso/Kconfig" 618 619source "lib/fonts/Kconfig" 620 621config SG_SPLIT 622 def_bool n 623 help 624 Provides a helper to split scatterlists into chunks, each chunk being 625 a scatterlist. This should be selected by a driver or an API which 626 whishes to split a scatterlist amongst multiple DMA channels. 627 628config SG_POOL 629 def_bool n 630 help 631 Provides a helper to allocate chained scatterlists. This should be 632 selected by a driver or an API which whishes to allocate chained 633 scatterlist. 634 635# 636# sg chaining option 637# 638 639config ARCH_NO_SG_CHAIN 640 def_bool n 641 642config ARCH_HAS_PMEM_API 643 bool 644 645config MEMREGION 646 bool 647 648config ARCH_HAS_CPU_CACHE_INVALIDATE_MEMREGION 649 bool 650 651config ARCH_HAS_MEMREMAP_COMPAT_ALIGN 652 bool 653 654# use memcpy to implement user copies for nommu architectures 655config UACCESS_MEMCPY 656 bool 657 658config ARCH_HAS_UACCESS_FLUSHCACHE 659 bool 660 661# arch has a concept of a recoverable synchronous exception due to a 662# memory-read error like x86 machine-check or ARM data-abort, and 663# implements copy_mc_to_{user,kernel} to abort and report 664# 'bytes-transferred' if that exception fires when accessing the source 665# buffer. 666config ARCH_HAS_COPY_MC 667 bool 668 669# Temporary. Goes away when all archs are cleaned up 670config ARCH_STACKWALK 671 bool 672 673config STACKDEPOT 674 bool 675 select STACKTRACE 676 help 677 Stack depot: stack trace storage that avoids duplication 678 679config STACKDEPOT_ALWAYS_INIT 680 bool 681 select STACKDEPOT 682 help 683 Always initialize stack depot during early boot 684 685config STACKDEPOT_MAX_FRAMES 686 int "Maximum number of frames in trace saved in stack depot" 687 range 1 256 688 default 64 689 depends on STACKDEPOT 690 691config REF_TRACKER 692 bool 693 depends on STACKTRACE_SUPPORT 694 select STACKDEPOT 695 696config SBITMAP 697 bool 698 699config PARMAN 700 tristate "parman" if COMPILE_TEST 701 702config OBJAGG 703 tristate "objagg" if COMPILE_TEST 704 705config LWQ_TEST 706 bool "Boot-time test for lwq queuing" 707 help 708 Run boot-time test of light-weight queuing. 709 710endmenu 711 712config GENERIC_IOREMAP 713 bool 714 715config GENERIC_LIB_ASHLDI3 716 bool 717 718config GENERIC_LIB_ASHRDI3 719 bool 720 721config GENERIC_LIB_LSHRDI3 722 bool 723 724config GENERIC_LIB_MULDI3 725 bool 726 727config GENERIC_LIB_CMPDI2 728 bool 729 730config GENERIC_LIB_UCMPDI2 731 bool 732 733config GENERIC_LIB_DEVMEM_IS_ALLOWED 734 bool 735 736config PLDMFW 737 bool 738 default n 739 740config ASN1_ENCODER 741 tristate 742 743config POLYNOMIAL 744 tristate 745 746config FIRMWARE_TABLE 747 bool 748 749config UNION_FIND 750 bool 751 752config MIN_HEAP 753 bool 754