diff mbox series

[v2,23/28] arm64: vdso: disable LTO

Message ID 20200903203053.3411268-24-samitolvanen@google.com
State New
Headers show
Series Add support for Clang LTO | expand

Commit Message

Sami Tolvanen Sept. 3, 2020, 8:30 p.m. UTC
Disable LTO for the vDSO by filtering out CC_FLAGS_LTO, as there's no
point in using link-time optimization for the small about of C code.

Signed-off-by: Sami Tolvanen <samitolvanen@google.com>
---
 arch/arm64/kernel/vdso/Makefile | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)

Comments

Kees Cook Sept. 3, 2020, 10:45 p.m. UTC | #1
On Thu, Sep 03, 2020 at 01:30:48PM -0700, Sami Tolvanen wrote:
> Disable LTO for the vDSO by filtering out CC_FLAGS_LTO, as there's no
> point in using link-time optimization for the small about of C code.
> 
> Signed-off-by: Sami Tolvanen <samitolvanen@google.com>

Yup. (And another replacement of the non-functional DISABLE_LTO...)

Reviewed-by: Kees Cook <keescook@chromium.org>
diff mbox series

Patch

diff --git a/arch/arm64/kernel/vdso/Makefile b/arch/arm64/kernel/vdso/Makefile
index 45d5cfe46429..aa47070a3ccf 100644
--- a/arch/arm64/kernel/vdso/Makefile
+++ b/arch/arm64/kernel/vdso/Makefile
@@ -30,8 +30,8 @@  ldflags-y := -shared -nostdlib -soname=linux-vdso.so.1 --hash-style=sysv	\
 ccflags-y := -fno-common -fno-builtin -fno-stack-protector -ffixed-x18
 ccflags-y += -DDISABLE_BRANCH_PROFILING
 
-CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE) -Os $(CC_FLAGS_SCS) $(GCC_PLUGINS_CFLAGS)
-KBUILD_CFLAGS			+= $(DISABLE_LTO)
+CFLAGS_REMOVE_vgettimeofday.o = $(CC_FLAGS_FTRACE) -Os $(CC_FLAGS_SCS) $(GCC_PLUGINS_CFLAGS) \
+				$(CC_FLAGS_LTO)
 KASAN_SANITIZE			:= n
 UBSAN_SANITIZE			:= n
 OBJECT_FILES_NON_STANDARD	:= y