From 67424d5a22124fa2d115faa8f32d12506989628f Mon Sep 17 00:00:00 2001 From: Andi Kleen Date: Sat, 8 Feb 2014 09:01:05 +0100 Subject: [PATCH] x86, lto: Disable LTO for the x86 VDSO The VDSO does not play well with LTO, so just disable LTO for it. Also pass a 32bit linker flag for the 32bit version. [ hpa: change braces to parens to match kernel Makefile style ] Signed-off-by: Andi Kleen Link: http://lkml.kernel.org/r/1391846481-31491-1-git-send-email-ak@linux.intel.com Signed-off-by: H. Peter Anvin --- arch/x86/vdso/Makefile | 10 +++++++--- 1 file changed, 7 insertions(+), 3 deletions(-) diff --git a/arch/x86/vdso/Makefile b/arch/x86/vdso/Makefile index fd14be1d1472..9206ac7961a5 100644 --- a/arch/x86/vdso/Makefile +++ b/arch/x86/vdso/Makefile @@ -2,6 +2,8 @@ # Building vDSO images for x86. # +KBUILD_CFLAGS += $(DISABLE_LTO) + VDSO64-$(CONFIG_X86_64) := y VDSOX32-$(CONFIG_X86_X32_ABI) := y VDSO32-$(CONFIG_X86_32) := y @@ -35,7 +37,8 @@ export CPPFLAGS_vdso.lds += -P -C VDSO_LDFLAGS_vdso.lds = -m64 -Wl,-soname=linux-vdso.so.1 \ -Wl,--no-undefined \ - -Wl,-z,max-page-size=4096 -Wl,-z,common-page-size=4096 + -Wl,-z,max-page-size=4096 -Wl,-z,common-page-size=4096 \ + $(DISABLE_LTO) $(obj)/vdso.o: $(src)/vdso.S $(obj)/vdso.so @@ -127,7 +130,7 @@ vdso32.so-$(VDSO32-y) += sysenter vdso32-images = $(vdso32.so-y:%=vdso32-%.so) CPPFLAGS_vdso32.lds = $(CPPFLAGS_vdso.lds) -VDSO_LDFLAGS_vdso32.lds = -m32 -Wl,-soname=linux-gate.so.1 +VDSO_LDFLAGS_vdso32.lds = -m32 -Wl,-m,elf_i386 -Wl,-soname=linux-gate.so.1 # This makes sure the $(obj) subdirectory exists even though vdso32/ # is not a kbuild sub-make subdirectory. @@ -181,7 +184,8 @@ quiet_cmd_vdso = VDSO $@ -Wl,-T,$(filter %.lds,$^) $(filter %.o,$^) && \ sh $(srctree)/$(src)/checkundef.sh '$(NM)' '$@' -VDSO_LDFLAGS = -fPIC -shared $(call cc-ldoption, -Wl$(comma)--hash-style=sysv) +VDSO_LDFLAGS = -fPIC -shared $(call cc-ldoption, -Wl$(comma)--hash-style=sysv) \ + $(LTO_CFLAGS) GCOV_PROFILE := n #