v4.19.13 snapshot.
diff --git a/lib/Kconfig b/lib/Kconfig
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+#
+# Library configuration
+#
+
+config BINARY_PRINTF
+ def_bool n
+
+menu "Library routines"
+
+config RAID6_PQ
+ tristate
+
+config BITREVERSE
+ tristate
+
+config HAVE_ARCH_BITREVERSE
+ bool
+ default n
+ depends on BITREVERSE
+ help
+ This option enables the use of hardware bit-reversal instructions on
+ architectures which support such operations.
+
+config RATIONAL
+ bool
+
+config GENERIC_STRNCPY_FROM_USER
+ bool
+
+config GENERIC_STRNLEN_USER
+ bool
+
+config GENERIC_NET_UTILS
+ bool
+
+config GENERIC_FIND_FIRST_BIT
+ bool
+
+config NO_GENERIC_PCI_IOPORT_MAP
+ bool
+
+config GENERIC_PCI_IOMAP
+ bool
+
+config GENERIC_IOMAP
+ bool
+ select GENERIC_PCI_IOMAP
+
+config STMP_DEVICE
+ bool
+
+config ARCH_USE_CMPXCHG_LOCKREF
+ bool
+
+config ARCH_HAS_FAST_MULTIPLIER
+ bool
+
+config INDIRECT_PIO
+ bool "Access I/O in non-MMIO mode"
+ depends on ARM64
+ help
+ On some platforms where no separate I/O space exists, there are I/O
+ hosts which can not be accessed in MMIO mode. Using the logical PIO
+ mechanism, the host-local I/O resource can be mapped into system
+ logic PIO space shared with MMIO hosts, such as PCI/PCIe, then the
+ system can access the I/O devices with the mapped-logic PIO through
+ I/O accessors.
+
+ This way has relatively little I/O performance cost. Please make
+ sure your devices really need this configure item enabled.
+
+ When in doubt, say N.
+
+config CRC_CCITT
+ tristate "CRC-CCITT functions"
+ help
+ This option is provided for the case where no in-kernel-tree
+ modules require CRC-CCITT functions, but a module built outside
+ the kernel tree does. Such modules that use library CRC-CCITT
+ functions require M here.
+
+config CRC16
+ tristate "CRC16 functions"
+ help
+ This option is provided for the case where no in-kernel-tree
+ modules require CRC16 functions, but a module built outside
+ the kernel tree does. Such modules that use library CRC16
+ functions require M here.
+
+config CRC_T10DIF
+ tristate "CRC calculation for the T10 Data Integrity Field"
+ select CRYPTO
+ select CRYPTO_CRCT10DIF
+ help
+ This option is only needed if a module that's not in the
+ kernel tree needs to calculate CRC checks for use with the
+ SCSI data integrity subsystem.
+
+config CRC_ITU_T
+ tristate "CRC ITU-T V.41 functions"
+ help
+ This option is provided for the case where no in-kernel-tree
+ modules require CRC ITU-T V.41 functions, but a module built outside
+ the kernel tree does. Such modules that use library CRC ITU-T V.41
+ functions require M here.
+
+config CRC32
+ tristate "CRC32/CRC32c functions"
+ default y
+ select BITREVERSE
+ help
+ This option is provided for the case where no in-kernel-tree
+ modules require CRC32/CRC32c functions, but a module built outside
+ the kernel tree does. Such modules that use library CRC32/CRC32c
+ functions require M here.
+
+config CRC32_SELFTEST
+ tristate "CRC32 perform self test on init"
+ depends on CRC32
+ help
+ This option enables the CRC32 library functions to perform a
+ self test on initialization. The self test computes crc32_le
+ and crc32_be over byte strings with random alignment and length
+ and computes the total elapsed time and number of bytes processed.
+
+choice
+ prompt "CRC32 implementation"
+ depends on CRC32
+ default CRC32_SLICEBY8
+ help
+ This option allows a kernel builder to override the default choice
+ of CRC32 algorithm. Choose the default ("slice by 8") unless you
+ know that you need one of the others.
+
+config CRC32_SLICEBY8
+ bool "Slice by 8 bytes"
+ help
+ Calculate checksum 8 bytes at a time with a clever slicing algorithm.
+ This is the fastest algorithm, but comes with a 8KiB lookup table.
+ Most modern processors have enough cache to hold this table without
+ thrashing the cache.
+
+ This is the default implementation choice. Choose this one unless
+ you have a good reason not to.
+
+config CRC32_SLICEBY4
+ bool "Slice by 4 bytes"
+ help
+ Calculate checksum 4 bytes at a time with a clever slicing algorithm.
+ This is a bit slower than slice by 8, but has a smaller 4KiB lookup
+ table.
+
+ Only choose this option if you know what you are doing.
+
+config CRC32_SARWATE
+ bool "Sarwate's Algorithm (one byte at a time)"
+ help
+ Calculate checksum a byte at a time using Sarwate's algorithm. This
+ is not particularly fast, but has a small 256 byte lookup table.
+
+ Only choose this option if you know what you are doing.
+
+config CRC32_BIT
+ bool "Classic Algorithm (one bit at a time)"
+ help
+ Calculate checksum one bit at a time. This is VERY slow, but has
+ no lookup table. This is provided as a debugging option.
+
+ Only choose this option if you are debugging crc32.
+
+endchoice
+
+config CRC64
+ tristate "CRC64 functions"
+ help
+ This option is provided for the case where no in-kernel-tree
+ modules require CRC64 functions, but a module built outside
+ the kernel tree does. Such modules that use library CRC64
+ functions require M here.
+
+config CRC4
+ tristate "CRC4 functions"
+ help
+ This option is provided for the case where no in-kernel-tree
+ modules require CRC4 functions, but a module built outside
+ the kernel tree does. Such modules that use library CRC4
+ functions require M here.
+
+config CRC7
+ tristate "CRC7 functions"
+ help
+ This option is provided for the case where no in-kernel-tree
+ modules require CRC7 functions, but a module built outside
+ the kernel tree does. Such modules that use library CRC7
+ functions require M here.
+
+config LIBCRC32C
+ tristate "CRC32c (Castagnoli, et al) Cyclic Redundancy-Check"
+ select CRYPTO
+ select CRYPTO_CRC32C
+ help
+ This option is provided for the case where no in-kernel-tree
+ modules require CRC32c functions, but a module built outside the
+ kernel tree does. Such modules that use library CRC32c functions
+ require M here. See Castagnoli93.
+ Module will be libcrc32c.
+
+config CRC8
+ tristate "CRC8 function"
+ help
+ This option provides CRC8 function. Drivers may select this
+ when they need to do cyclic redundancy check according CRC8
+ algorithm. Module will be called crc8.
+
+config XXHASH
+ tristate
+
+config AUDIT_GENERIC
+ bool
+ depends on AUDIT && !AUDIT_ARCH
+ default y
+
+config AUDIT_ARCH_COMPAT_GENERIC
+ bool
+ default n
+
+config AUDIT_COMPAT_GENERIC
+ bool
+ depends on AUDIT_GENERIC && AUDIT_ARCH_COMPAT_GENERIC && COMPAT
+ default y
+
+config RANDOM32_SELFTEST
+ bool "PRNG perform self test on init"
+ help
+ This option enables the 32 bit PRNG library functions to perform a
+ self test on initialization.
+
+#
+# compression support is select'ed if needed
+#
+config 842_COMPRESS
+ select CRC32
+ tristate
+
+config 842_DECOMPRESS
+ select CRC32
+ tristate
+
+config ZLIB_INFLATE
+ tristate
+
+config ZLIB_DEFLATE
+ tristate
+ select BITREVERSE
+
+config LZO_COMPRESS
+ tristate
+
+config LZO_DECOMPRESS
+ tristate
+
+config LZ4_COMPRESS
+ tristate
+
+config LZ4HC_COMPRESS
+ tristate
+
+config LZ4_DECOMPRESS
+ tristate
+
+config ZSTD_COMPRESS
+ select XXHASH
+ tristate
+
+config ZSTD_DECOMPRESS
+ select XXHASH
+ tristate
+
+source "lib/xz/Kconfig"
+
+#
+# These all provide a common interface (hence the apparent duplication with
+# ZLIB_INFLATE; DECOMPRESS_GZIP is just a wrapper.)
+#
+config DECOMPRESS_GZIP
+ select ZLIB_INFLATE
+ tristate
+
+config DECOMPRESS_BZIP2
+ tristate
+
+config DECOMPRESS_LZMA
+ tristate
+
+config DECOMPRESS_XZ
+ select XZ_DEC
+ tristate
+
+config DECOMPRESS_LZO
+ select LZO_DECOMPRESS
+ tristate
+
+config DECOMPRESS_LZ4
+ select LZ4_DECOMPRESS
+ tristate
+
+#
+# Generic allocator support is selected if needed
+#
+config GENERIC_ALLOCATOR
+ bool
+
+#
+# reed solomon support is select'ed if needed
+#
+config REED_SOLOMON
+ tristate
+
+config REED_SOLOMON_ENC8
+ bool
+
+config REED_SOLOMON_DEC8
+ bool
+
+config REED_SOLOMON_ENC16
+ bool
+
+config REED_SOLOMON_DEC16
+ bool
+
+#
+# BCH support is selected if needed
+#
+config BCH
+ tristate
+
+config BCH_CONST_PARAMS
+ bool
+ help
+ Drivers may select this option to force specific constant
+ values for parameters 'm' (Galois field order) and 't'
+ (error correction capability). Those specific values must
+ be set by declaring default values for symbols BCH_CONST_M
+ and BCH_CONST_T.
+ Doing so will enable extra compiler optimizations,
+ improving encoding and decoding performance up to 2x for
+ usual (m,t) values (typically such that m*t < 200).
+ When this option is selected, the BCH library supports
+ only a single (m,t) configuration. This is mainly useful
+ for NAND flash board drivers requiring known, fixed BCH
+ parameters.
+
+config BCH_CONST_M
+ int
+ range 5 15
+ help
+ Constant value for Galois field order 'm'. If 'k' is the
+ number of data bits to protect, 'm' should be chosen such
+ that (k + m*t) <= 2**m - 1.
+ Drivers should declare a default value for this symbol if
+ they select option BCH_CONST_PARAMS.
+
+config BCH_CONST_T
+ int
+ help
+ Constant value for error correction capability in bits 't'.
+ Drivers should declare a default value for this symbol if
+ they select option BCH_CONST_PARAMS.
+
+#
+# Textsearch support is select'ed if needed
+#
+config TEXTSEARCH
+ bool
+
+config TEXTSEARCH_KMP
+ tristate
+
+config TEXTSEARCH_BM
+ tristate
+
+config TEXTSEARCH_FSM
+ tristate
+
+config BTREE
+ bool
+
+config INTERVAL_TREE
+ bool
+ help
+ Simple, embeddable, interval-tree. Can find the start of an
+ overlapping range in log(n) time and then iterate over all
+ overlapping nodes. The algorithm is implemented as an
+ augmented rbtree.
+
+ See:
+
+ Documentation/rbtree.txt
+
+ for more information.
+
+config RADIX_TREE_MULTIORDER
+ bool
+
+config ASSOCIATIVE_ARRAY
+ bool
+ help
+ Generic associative array. Can be searched and iterated over whilst
+ it is being modified. It is also reasonably quick to search and
+ modify. The algorithms are non-recursive, and the trees are highly
+ capacious.
+
+ See:
+
+ Documentation/core-api/assoc_array.rst
+
+ for more information.
+
+config HAS_IOMEM
+ bool
+ depends on !NO_IOMEM
+ select GENERIC_IO
+ default y
+
+config HAS_IOPORT_MAP
+ bool
+ depends on HAS_IOMEM && !NO_IOPORT_MAP
+ default y
+
+source "kernel/dma/Kconfig"
+
+config SGL_ALLOC
+ bool
+ default n
+
+config IOMMU_HELPER
+ bool
+
+config CHECK_SIGNATURE
+ bool
+
+config CPUMASK_OFFSTACK
+ bool "Force CPU masks off stack" if DEBUG_PER_CPU_MAPS
+ help
+ Use dynamic allocation for cpumask_var_t, instead of putting
+ them on the stack. This is a bit more expensive, but avoids
+ stack overflow.
+
+config CPU_RMAP
+ bool
+ depends on SMP
+
+config DQL
+ bool
+
+config GLOB
+ bool
+# This actually supports modular compilation, but the module overhead
+# is ridiculous for the amount of code involved. Until an out-of-tree
+# driver asks for it, we'll just link it directly it into the kernel
+# when required. Since we're ignoring out-of-tree users, there's also
+# no need bother prompting for a manual decision:
+# prompt "glob_match() function"
+ help
+ This option provides a glob_match function for performing
+ simple text pattern matching. It originated in the ATA code
+ to blacklist particular drive models, but other device drivers
+ may need similar functionality.
+
+ All drivers in the Linux kernel tree that require this function
+ should automatically select this option. Say N unless you
+ are compiling an out-of tree driver which tells you that it
+ depends on this.
+
+config GLOB_SELFTEST
+ tristate "glob self-test on init"
+ depends on GLOB
+ help
+ This option enables a simple self-test of the glob_match
+ function on startup. It is primarily useful for people
+ working on the code to ensure they haven't introduced any
+ regressions.
+
+ It only adds a little bit of code and slows kernel boot (or
+ module load) by a small amount, so you're welcome to play with
+ it, but you probably don't need it.
+
+#
+# Netlink attribute parsing support is select'ed if needed
+#
+config NLATTR
+ bool
+
+#
+# Generic 64-bit atomic support is selected if needed
+#
+config GENERIC_ATOMIC64
+ bool
+
+config LRU_CACHE
+ tristate
+
+config CLZ_TAB
+ bool
+
+config CORDIC
+ tristate "CORDIC algorithm"
+ help
+ This option provides an implementation of the CORDIC algorithm;
+ calculations are in fixed point. Module will be called cordic.
+
+config DDR
+ bool "JEDEC DDR data"
+ help
+ Data from JEDEC specs for DDR SDRAM memories,
+ particularly the AC timing parameters and addressing
+ information. This data is useful for drivers handling
+ DDR SDRAM controllers.
+
+config IRQ_POLL
+ bool "IRQ polling library"
+ help
+ Helper library to poll interrupt mitigation using polling.
+
+config MPILIB
+ tristate
+ select CLZ_TAB
+ help
+ Multiprecision maths library from GnuPG.
+ It is used to implement RSA digital signature verification,
+ which is used by IMA/EVM digital signature extension.
+
+config SIGNATURE
+ tristate
+ depends on KEYS
+ select CRYPTO
+ select CRYPTO_SHA1
+ select MPILIB
+ help
+ Digital signature verification. Currently only RSA is supported.
+ Implementation is done using GnuPG MPI library
+
+#
+# libfdt files, only selected if needed.
+#
+config LIBFDT
+ bool
+
+config OID_REGISTRY
+ tristate
+ help
+ Enable fast lookup object identifier registry.
+
+config UCS2_STRING
+ tristate
+
+source "lib/fonts/Kconfig"
+
+config SG_SPLIT
+ def_bool n
+ help
+ Provides a helper to split scatterlists into chunks, each chunk being
+ a scatterlist. This should be selected by a driver or an API which
+ whishes to split a scatterlist amongst multiple DMA channels.
+
+config SG_POOL
+ def_bool n
+ help
+ Provides a helper to allocate chained scatterlists. This should be
+ selected by a driver or an API which whishes to allocate chained
+ scatterlist.
+
+#
+# sg chaining option
+#
+
+config ARCH_HAS_SG_CHAIN
+ def_bool n
+
+config ARCH_HAS_PMEM_API
+ bool
+
+config ARCH_HAS_UACCESS_FLUSHCACHE
+ bool
+
+config ARCH_HAS_UACCESS_MCSAFE
+ bool
+
+config STACKDEPOT
+ bool
+ select STACKTRACE
+
+config SBITMAP
+ bool
+
+config PARMAN
+ tristate "parman" if COMPILE_TEST
+
+config PRIME_NUMBERS
+ tristate
+
+config STRING_SELFTEST
+ tristate "Test string functions"
+
+endmenu
+
+config GENERIC_LIB_ASHLDI3
+ bool
+
+config GENERIC_LIB_ASHRDI3
+ bool
+
+config GENERIC_LIB_LSHRDI3
+ bool
+
+config GENERIC_LIB_MULDI3
+ bool
+
+config GENERIC_LIB_CMPDI2
+ bool
+
+config GENERIC_LIB_UCMPDI2
+ bool