From: Andre Przywara <andre.przywara@xxxxxxx> [ Upstream commit d7a49291d786b4400996afe3afcc3ef5eeb6f0ef ] The "bti" selftests are built with -nostdlib, which apparently automatically creates a statically linked binary, which is what we want and need for BTI (to avoid interactions with the dynamic linker). However this is not true when building a PIE binary, which some toolchains (Ubuntu) configure as the default. When compiling btitest with such a toolchain, it will create a dynamically linked binary, which will probably fail some tests, as the dynamic linker might not support BTI: =================== TAP version 13 1..18 not ok 1 nohint_func/call_using_br_x0 not ok 2 nohint_func/call_using_br_x16 not ok 3 nohint_func/call_using_blr .... =================== To make sure we create static binaries, add an explicit -static on the linker command line. This forces static linking even if the toolchain defaults to PIE builds, and fixes btitest runs on BTI enabled machines. Signed-off-by: Andre Przywara <andre.przywara@xxxxxxx> Reviewed-by: Mark Brown <broonie@xxxxxxxxxx> Fixes: 314bcbf09f14 ("kselftest: arm64: Add BTI tests") Link: https://lore.kernel.org/r/20220511172129.2078337-1-andre.przywara@xxxxxxx Signed-off-by: Catalin Marinas <catalin.marinas@xxxxxxx> Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx> --- tools/testing/selftests/arm64/bti/Makefile | 4 ++-- 1 file changed, 2 insertions(+), 2 deletions(-) diff --git a/tools/testing/selftests/arm64/bti/Makefile b/tools/testing/selftests/arm64/bti/Makefile index 73e013c082a6..dafa1c2aa5c4 100644 --- a/tools/testing/selftests/arm64/bti/Makefile +++ b/tools/testing/selftests/arm64/bti/Makefile @@ -39,7 +39,7 @@ BTI_OBJS = \ teststubs-bti.o \ trampoline-bti.o gen/btitest: $(BTI_OBJS) - $(CC) $(CFLAGS_BTI) $(CFLAGS_COMMON) -nostdlib -o $@ $^ + $(CC) $(CFLAGS_BTI) $(CFLAGS_COMMON) -nostdlib -static -o $@ $^ NOBTI_OBJS = \ test-nobti.o \ @@ -50,7 +50,7 @@ NOBTI_OBJS = \ teststubs-nobti.o \ trampoline-nobti.o gen/nobtitest: $(NOBTI_OBJS) - $(CC) $(CFLAGS_BTI) $(CFLAGS_COMMON) -nostdlib -o $@ $^ + $(CC) $(CFLAGS_BTI) $(CFLAGS_COMMON) -nostdlib -static -o $@ $^ # Including KSFT lib.mk here will also mangle the TEST_GEN_PROGS list # to account for any OUTPUT target-dirs optionally provided by -- 2.35.1