From 69ca372c100fba99c78ef826a1795aa86e4f01a8 Mon Sep 17 00:00:00 2001 From: Andrey Konovalov Date: Tue, 10 Apr 2018 16:30:39 -0700 Subject: [PATCH] kasan: prevent compiler from optimizing away memset in tests A compiler can optimize away memset calls by replacing them with mov instructions. There are KASAN tests that specifically test that KASAN correctly handles memset calls so we don't want this optimization to happen. The solution is to add -fno-builtin flag to test_kasan.ko Link: http://lkml.kernel.org/r/105ec9a308b2abedb1a0d1fdced0c22d765e4732.1519924383.git.andreyknvl@google.com Signed-off-by: Andrey Konovalov Acked-by: Andrey Ryabinin Cc: Alexander Potapenko Cc: Dmitry Vyukov Cc: Geert Uytterhoeven Cc: Nick Terrell Cc: Chris Mason Cc: Yury Norov Cc: Al Viro Cc: "Luis R . Rodriguez" Cc: Palmer Dabbelt Cc: "Paul E . McKenney" Cc: Jeff Layton Cc: "Jason A . Donenfeld" Cc: Kostya Serebryany Signed-off-by: Andrew Morton Signed-off-by: Linus Torvalds --- lib/Makefile | 1 + 1 file changed, 1 insertion(+) diff --git a/lib/Makefile b/lib/Makefile index 8fc0d3a9b34f..6200f978740d 100644 --- a/lib/Makefile +++ b/lib/Makefile @@ -53,6 +53,7 @@ obj-$(CONFIG_TEST_FIRMWARE) += test_firmware.o obj-$(CONFIG_TEST_SYSCTL) += test_sysctl.o obj-$(CONFIG_TEST_HASH) += test_hash.o test_siphash.o obj-$(CONFIG_TEST_KASAN) += test_kasan.o +CFLAGS_test_kasan.o += -fno-builtin obj-$(CONFIG_TEST_KSTRTOX) += test-kstrtox.o obj-$(CONFIG_TEST_LIST_SORT) += test_list_sort.o obj-$(CONFIG_TEST_LKM) += test_module.o