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