Nick Desaulniers
7eceaf5bbf
lib/string.c: implement a basic bcmp ...
[ Upstream commit 5f074f3e192f10c9fade898b9b3b8812e3d83342 ]
A recent optimization in Clang (r355672) lowers comparisons of the
return value of memcmp against zero to comparisons of the return value
of bcmp against zero. This helps some platforms that implement bcmp
more efficiently than memcmp. glibc simply aliases bcmp to memcmp, but
an optimized implementation is in the works.
This results in linkage failures for all targets with Clang due to the
undefined symbol. For now, just implement bcmp as a tailcail to memcmp
to unbreak the build. This routine can be further optimized in the
future.
Other ideas discussed:
* A weak alias was discussed, but breaks for architectures that define
their own implementations of memcmp since aliases to declarations are
not permitted (only definitions). Arch-specific memcmp
implementations typically declare memcmp in C headers, but implement
them in assembly.
* -ffreestanding also is used sporadically throughout the kernel.
* -fno-builtin-bcmp doesn't work when doing LTO.
Link: https://bugs.llvm.org/show_bug.cgi?id=41035
Link: https://code.woboq.org/userspace/glibc/string/memcmp.c.html#bcmp
Link: 8e16d73346https://github.com/ClangBuiltLinux/linux/issues/416
Link: http://lkml.kernel.org/r/20190313211335.165605-1-ndesaulniers@google.com
Signed-off-by: Nick Desaulniers <ndesaulniers@google.com>
Reported-by: Nathan Chancellor <natechancellor@gmail.com>
Reported-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Suggested-by: Arnd Bergmann <arnd@arndb.de>
Suggested-by: James Y Knight <jyknight@google.com>
Suggested-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Suggested-by: Nathan Chancellor <natechancellor@gmail.com>
Suggested-by: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Acked-by: Steven Rostedt (VMware) <rostedt@goodmis.org>
Reviewed-by: Nathan Chancellor <natechancellor@gmail.com>
Tested-by: Nathan Chancellor <natechancellor@gmail.com>
Reviewed-by: Masahiro Yamada <yamada.masahiro@socionext.com>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Cc: David Laight <David.Laight@ACULAB.COM>
Cc: Rasmus Villemoes <linux@rasmusvillemoes.dk>
Cc: Namhyung Kim <namhyung@kernel.org>
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
Cc: Alexander Shishkin <alexander.shishkin@linux.intel.com>
Cc: Dan Williams <dan.j.williams@intel.com>
Cc: <stable@vger.kernel.org>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>
2019-04-17 08:36:39 +02:00
Merge branch 'for-linus' of git://git.kernel.org/pub/scm/linux/kernel/git/jikos/trivial
2016-03-17 21:38:27 -07:00
fonts: Add 6x10 font
2014-10-09 11:35:48 +03:00
lz4: fix bogus gcc warning
2017-09-02 07:07:54 +02:00
lzo: check for length overrun in variable length encoding.
2014-09-28 11:08:01 +02:00
lib/mpi: Fix umul_ppmm() for MIPS64r6
2018-03-03 10:23:23 +01:00
ARM: 8833/1: Ensure that NEON code always compiles with Clang
2019-04-05 22:29:11 +02:00
lib/xz: enable all filters by default in Kconfig
2014-06-04 16:54:18 -07:00
zlib_deflate/deftree: remove bi_reverse()
2015-09-10 13:29:01 -07:00
zlib: clean up some dead code
2014-08-06 18:01:24 -07:00
ASN.1: check for error from ASN1_OP_END__ACT actions
2017-12-14 09:28:12 +01:00
assoc_array: Fix shortcut creation
2019-03-23 13:19:42 +01:00
locking/atomic: Implement atomic{,64,_long}_fetch_{add,sub,and,andnot,or,xor}{,_relaxed,_acquire,_release}()
2016-06-16 10:48:32 +02:00
atomic64: no need for CONFIG_ARCH_HAS_ATOMIC64_DEC_IF_POSITIVE
2016-10-07 18:46:30 -07:00
syscalls: implement execveat() system call
2014-12-13 12:42:51 -08:00
lib/bitmap.c: enhance bitmap syntax
2016-10-11 15:06:30 -07:00
ARM: 8187/1: add CONFIG_HAVE_ARCH_BITREVERSE to support rbit instruction
2014-12-22 16:43:06 +00:00
kprobes: Prohibit probing on bsearch()
2019-04-05 22:29:11 +02:00
treewide: Remove old email address
2015-11-23 09:44:58 +01:00
lib/bug.c: use common WARN helper
2016-03-17 15:09:34 -07:00
random: replace non-blocking pool with a Chacha20-based CRNG
2016-07-03 00:57:23 -04:00
ipv4: Update parameters for csum_tcpudp_magic to their original types
2016-03-13 23:55:13 -04:00
lib/clz_ctz.c: add prototype declarations in lib/clz_ctz.c
2014-04-03 16:21:12 -07:00
lib/cmdline.c: fix get_options() overflow while parsing ranges
2017-06-29 13:00:28 +02:00
audit: Add generic compat syscall support
2014-03-20 10:11:35 -04:00
fault-injection/cpu: Convert to hotplug state machine
2016-09-19 21:44:31 +02:00
sched/topology: Rename topology_thread_cpumask() to topology_sibling_cpumask()
2015-05-27 15:22:15 +02:00
sched/fair, cpumask: Export for_each_cpu_wrap()
2017-07-21 07:42:23 +02:00
lib: crc-itu-t.[ch] fix 0x0x prefix in integer constants
2015-05-26 15:26:43 +02:00
lib: introduce crc_t10dif_update()
2015-05-30 22:42:24 -07:00
lib/crc7: Shift crc7() output left 1 bit
2014-05-16 14:26:52 -04:00
crc32: use ktime_get_ns() for measurement
2016-08-02 19:35:08 -04:00
kbuild: include core debug info when DEBUG_INFO_REDUCED
2015-06-11 15:08:32 +02:00
locking/lockdep: Fix debug_locks off performance problem
2018-11-13 11:16:48 -08:00
debugobjects: avoid recursive calls with kmemleak
2018-12-17 09:38:35 +01:00
lib/decompress: set the compressor name to NULL on error
2015-07-17 16:39:54 -07:00
lib/decompressors: use real out buf size for gunzip with kernel
2015-09-10 13:29:01 -07:00
lib/decompressors: use real out buf size for gunzip with kernel
2015-09-10 13:29:01 -07:00
lib/decompressors: use real out buf size for gunzip with kernel
2015-09-10 13:29:01 -07:00
lib/decompress_unlzma: Do a NULL check for pointer
2015-09-10 13:29:01 -07:00
lib/decompressors: use real out buf size for gunzip with kernel
2015-09-10 13:29:01 -07:00
lib/decompressors: use real out buf size for gunzip with kernel
2015-09-10 13:29:01 -07:00
devres: use to_pci_dev()
2016-02-07 23:17:59 -08:00
lib/digsig: fix dereference of NULL user_key_payload
2017-10-27 10:38:08 +02:00
__div64_32(): make it overridable at compile time
2015-11-16 14:42:12 -05:00
dmaengine updates for 4.8-rc1
2016-10-06 17:13:54 -07:00
dma-mapping: use unsigned long for dma_attrs
2016-08-04 08:50:07 -04:00
dump_stack: avoid potential deadlocks
2016-02-05 18:10:40 -08:00
dynamic-debug-howto: fix optional/omitted ending line number to be LARGE instead of 0
2017-12-14 09:28:22 +01:00
lib/dynamic_queue_limits.c: simplify includes
2015-02-12 18:54:15 -08:00
lib/cpio: Make find_cpio_data()'s offset arg optional
2016-06-08 11:04:19 +02:00
extable: add support for relative extables to search and sort routines
2016-02-24 14:57:26 +00:00
fault-inject: fix inverted interval/probability values in printk
2015-10-23 17:55:10 +09:00
lib: add fdt_empty_tree.c
2014-04-30 19:49:37 +01:00
lib: rename lib/find_next_bit.c to lib/find_bit.c
2015-04-17 09:03:54 -04:00
reciprocal_divide: update/correction of the algorithm
2014-01-21 23:17:20 -08:00
lib+mm: fix few spelling mistakes
2016-02-15 11:18:23 +01:00
lib/GCD.c: use binary GCD algorithm instead of Euclidean
2016-05-20 17:58:30 -07:00
lib: crc32: constify crc32 lookup table
2015-02-13 21:21:35 -08:00
lib/genalloc.c: make the avail variable an atomic_long_t
2017-12-14 09:28:22 +01:00
lib/glob.c: add CONFIG_GLOB_SELFTEST
2014-08-06 18:01:25 -07:00
lib/halfmd4.c: use rol32 inline function in the ROUND macro
2015-11-06 17:50:42 -08:00
lib/hexdump.c: truncate output in case of overflow
2015-11-06 17:50:42 -08:00
x86/hweight: Get rid of the special calling convention
2016-06-08 15:01:02 +02:00
mm, page_alloc: distinguish between being unable to sleep, unwilling to sleep and avoiding waking kswapd
2015-11-06 17:50:42 -08:00
lib/int_sqrt: optimize initial value compute
2019-04-05 22:29:04 +02:00
lib/interval_tree.c: simplify includes
2015-02-12 18:54:15 -08:00
lib/interval_tree_test.c: allow users to limit scope of endpoint
2018-12-21 14:11:30 +01:00
Kconfig: rename HAS_IOPORT to HAS_IOPORT_MAP
2014-04-07 16:36:11 -07:00
lib/iomap_copy.c: add __ioread32_copy()
2016-01-20 17:09:18 -08:00
Merge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc
2015-11-05 16:34:48 -08:00
lib/iommu-helper: skip to next segment
2016-08-02 19:35:07 -04:00
ioremap: Update pgtable free interfaces with addr
2018-08-17 20:59:29 +02:00
new privimitive: iov_iter_revert()
2017-04-21 09:31:21 +02:00
This adds a new gcc plugin named "latent_entropy". It is designed to
2016-10-15 10:03:15 -07:00
lib/is_single_threaded.c: change current_is_single_threaded() to use for_each_thread()
2015-11-06 17:50:42 -08:00
lib/kasprintf.c: add sanity check to kvasprintf
2016-01-16 11:17:27 -08:00
Merge branch 'akpm' (patches from Andrew)
2016-10-07 21:38:00 -07:00
kasan: rework Kconfig settings
2018-02-25 11:05:55 +01:00
mm, kasan: switch SLUB to stackdepot, enable memory quarantine for SLUB
2016-07-28 16:07:41 -07:00
kgdb: depends on VT
2016-05-23 17:04:14 -07:00
ubsan: allow to disable the null sanitizer
2016-09-20 14:26:08 +02:00
kfifo: use BUG_ON
2014-08-08 15:57:25 -07:00
scsi: klist: Make it safe to use klists in atomic context
2018-10-03 17:01:45 -07:00
kobject: Replace strncpy with memcpy
2018-12-08 13:05:05 +01:00
lib/kobject_uevent.c: remove redundant include
2015-02-12 18:54:15 -08:00
lib/kstrtox.c: smaller _parse_integer()
2016-10-11 15:06:30 -07:00
block: fix blk_stack_limits() regression due to lcm() change
2015-03-31 09:45:50 -06:00
crypto: Work around deallocated stack frame reference gcc bug on sparc.
2017-06-24 07:11:17 +02:00
list: kill list_force_poison()
2016-03-09 15:43:42 -08:00
lib/list_sort: use late_initcall to hook in self tests
2015-06-16 14:12:35 -04:00
lib/llist.c: fix data race in llist_del_first
2015-11-06 17:50:42 -08:00
locking/selftest: Fix output since KERN_CONT changes
2016-11-25 07:12:19 +01:00
locking/lockref: Remove homebrew cmpxchg64_relaxed() macro definition
2015-08-12 11:59:04 +02:00
lru_cache: Converted lc_seq_printf_status to return void
2015-11-25 09:22:02 -07:00
kcov: do not instrument lib/stackdepot.c
2016-10-11 15:06:32 -07:00
lib/md5.c: simplify include
2015-02-12 18:54:15 -08:00
mac_pton: Use bool not int return
2014-06-25 17:45:43 -07:00
net: Add support for CHANGEUPPER notifier error injection
2015-12-03 11:49:23 -05:00
libnl: fix help of _64bit functions
2016-04-23 20:13:24 -04:00
nmi_backtrace: generate one-line reports for idle cpus
2016-10-07 18:46:30 -07:00
include/linux/nodemask.h: create next_node_in() helper
2016-05-19 19:12:14 -07:00
509: fix printing uninitialized stack memory when OID is empty
2018-02-25 11:05:48 +01:00
once: make helper generic for calling functions once
2015-10-08 05:26:36 -07:00
lib/parser.c: put EXPORT_SYMBOLs in the conventional place
2014-01-23 16:36:55 -08:00
libnvdimm for 4.3:
2015-09-08 14:35:59 -07:00
percpu-refcount: init ->confirm_switch member properly
2016-08-11 13:52:23 -04:00
percpu_counter: update debugobjects fixup callbacks return type
2016-05-19 19:12:14 -07:00
mm, page_alloc: rename __GFP_WAIT to __GFP_RECLAIM
2015-11-06 17:50:42 -08:00
lib/plist.c: remove redundant include
2015-02-12 18:54:16 -08:00
Revert "radix tree test suite: fix compilation"
2016-12-09 10:41:42 -08:00
This adds a new gcc plugin named "latent_entropy". It is designed to
2016-10-15 10:03:15 -07:00
lib/ratelimit.c: use deferred printk() version
2017-10-12 11:51:19 +02:00
Introduce rb_replace_node_rcu()
2016-07-06 10:51:14 +01:00
lib/rbtree-test: lower default params
2018-12-21 14:11:30 +01:00
reciprocal_divide: update/correction of the algorithm
2014-01-21 23:17:20 -08:00
rhashtable: add schedule points
2018-10-18 09:13:24 +02:00
sbitmap: initialize weight to zero
2016-09-19 08:19:40 -06:00
scatterlist: fix a typo in comment block of sg_miter_stop()
2016-02-08 10:15:17 -08:00
seq_buf: Make seq_buf_puts() null-terminate the buffer
2019-02-12 19:44:57 +01:00
lib: scatterlist: move SG pool code from SCSI driver to lib/sg_pool.c
2016-04-15 16:53:14 -04:00
lib: scatterlist: add sg splitting function
2015-08-24 14:28:01 -06:00
lib: EXPORT_SYMBOL sha_init
2015-03-23 22:12:08 -04:00
lib/show_mem.c: correct reserved memory calculation
2015-09-08 15:35:28 -07:00
percpu: add preemption checks to __this_cpu ops
2014-04-07 16:36:14 -07:00
lib/sort: Add 64 bit swap function
2015-06-25 17:00:40 -07:00
lib/stackdepot: export save/fetch stack for drivers
2016-11-11 08:12:37 -08:00
lib/stmp_device.c: replace module.h include
2015-02-12 18:54:16 -08:00
lib/string.c: implement a basic bcmp
2019-04-17 08:36:39 +02:00
string_helpers: add kstrdup_quotable_file
2016-04-21 10:47:26 +10:00
lib: harden strncpy_from_user
2016-10-11 15:06:30 -07:00
unsafe_[get|put]_user: change interface to use a error target label
2016-08-08 13:02:01 -07:00
swiotlb: clean up reporting
2018-12-13 09:20:29 +01:00
lib/syscall: Clear return values when no stack
2017-04-08 09:30:35 +02:00
kstrto*: accept "-0" for signed conversion
2015-09-10 13:29:01 -07:00
lib/test-string_helpers.c: fix and improve string_get_size() tests
2016-02-03 08:28:43 -08:00
test_bitmap: unit tests for lib/bitmap.c
2016-02-19 22:54:09 -05:00
test_bpf: Fix testing with CONFIG_BPF_JIT_ALWAYS_ON=y on other arches
2018-11-10 07:42:54 -08:00
test: firmware_class: add asynchronous request trigger
2016-01-07 13:44:22 -07:00
lib/test_hash.c: fix warning in preprocessor symbol evaluation
2016-09-01 17:52:01 -07:00
test_hexdump: use memcpy instead of strncpy
2018-12-08 13:05:04 +01:00
kasan: support use-after-scope detection
2016-11-30 16:32:52 -08:00
test: add minimal module for verification testing
2014-01-23 16:36:57 -08:00
mm, printk: introduce new format string for flags
2016-03-15 16:55:16 -07:00
rhashtable-test: Fix max_size parameter description
2016-08-08 12:52:42 -07:00
locking/static_keys: Provide a selftest
2015-08-03 11:51:12 +02:00
locking/static_keys: Avoid nested functions
2016-02-09 10:27:29 +01:00
usercopy: Adjust tests to deal with SMAP/PAN
2017-06-14 15:06:05 +02:00
lib/uuid: add a test module
2016-05-30 15:26:57 -07:00
lib/textsearch.c: remove textsearch_put reference from comments
2014-10-14 02:18:14 +02:00
timerqueue: Let timerqueue_add/del return information
2015-04-22 17:06:49 +02:00
lib/ubsan.c: don't mark __ubsan_handle_builtin_unreachable as noreturn
2018-11-21 09:26:03 +01:00
lib/ubsan: add type mismatch handler for new GCC/Clang
2018-02-17 13:21:20 +01:00
lib/ucs2_string: Speed up ucs2_utf8size()
2016-09-09 16:08:46 +01:00
lib/uuid.c: use correct offset in uuid parser
2016-05-30 15:26:57 -07:00
lib/vsprintf: Remove atomic-unsafe support for %pCr
2018-07-03 11:23:06 +02:00
lib/win_minmax: windowed min or max estimator
2016-09-21 00:22:59 -04:00
7eceaf5bbf