diff options
| author | Alexander Potapenko <glider@google.com> | 2020-04-06 20:10:19 -0700 |
|---|---|---|
| committer | Linus Torvalds <torvalds@linux-foundation.org> | 2020-04-07 10:43:43 -0700 |
| commit | 7b65942fb2f0ac939be9c659bb889e78b399f84e (patch) | |
| tree | 783d56f4fb7ed1c67393cc5577652a4c8ca06780 /lib | |
| parent | 69866e156ce28c47dc0085b5ba5e734f5511812e (diff) | |
lib/stackdepot.c: build with -fno-builtin
Clang may replace stackdepot_memcmp() with a call to instrumented bcmp(),
which is exactly what we wanted to avoid creating stackdepot_memcmp().
Building the file with -fno-builtin prevents such optimizations.
This patch has been previously mailed as part of KMSAN RFC patch series.
Signed-off-by: Alexander Potapenko <glider@google.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Cc: Vegard Nossum <vegard.nossum@oracle.com>
Cc: Dmitry Vyukov <dvyukov@google.com>
Cc: Marco Elver <elver@google.com>
Cc: Andrey Konovalov <andreyknvl@google.com>
Cc: Sergey Senozhatsky <sergey.senozhatsky@gmail.com>
Cc: Arnd Bergmann <arnd@arndb.de>
Cc: Andrey Ryabinin <aryabinin@virtuozzo.com>
Link: http://lkml.kernel.org/r/20200220141916.55455-2-glider@google.com
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/Makefile | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/lib/Makefile b/lib/Makefile index 93d05ff4f501..3fc06399295d 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -223,6 +223,10 @@ obj-$(CONFIG_MEMREGION) += memregion.o obj-$(CONFIG_STMP_DEVICE) += stmp_device.o obj-$(CONFIG_IRQ_POLL) += irq_poll.o +# stackdepot.c should not be instrumented or call instrumented functions. +# Prevent the compiler from calling builtins like memcmp() or bcmp() from this +# file. +CFLAGS_stackdepot.o += -fno-builtin obj-$(CONFIG_STACKDEPOT) += stackdepot.o KASAN_SANITIZE_stackdepot.o := n KCOV_INSTRUMENT_stackdepot.o := n |