commit 008cc907de327d83a0be609cd495fccb0e5dfa4c
author H. Peter Anvin <hpa@linux.intel.com> Mon Mar 17 23:22:12 2014 +0100
committer H. Peter Anvin <hpa@linux.intel.com> Tue Mar 18 12:52:48 2014 -0700
tree e649886b0683a3c9cb3e45bd00163a1a1cf8d5d6
parent 309944be296efbb3ca4737d12ef49d2ba97cbecc

x86, vdso32: Disable stack protector, adjust optimizations

For the 32-bit VDSO, match the 64-bit VDSO in:

1. Disable the stack protector.
2. Use -fno-omit-frame-pointer for user space debugging sanity.
3. Use -foptimize-sibling-calls like the 64-bit VDSO does.

Reported-by: Ingo Molnar <mingo@kernel.org>
Signed-off-by: Stefani Seibold <stefani@seibold.net>
Link: http://lkml.kernel.org/r/1395094933-14252-13-git-send-email-stefani@seibold.net
Signed-off-by: H. Peter Anvin <hpa@linux.intel.com>

arch/x86/vdso/Makefile

diff --git a/arch/x86/vdso/Makefile b/arch/x86/vdso/Makefile
index 6cef7a1..a2de5fc 100644
--- a/arch/x86/vdso/Makefile
+++ b/arch/x86/vdso/Makefile
@@ -151,6 +151,9 @@
 KBUILD_CFLAGS_32 := $(filter-out -fno-pic,$(KBUILD_CFLAGS_32))
 KBUILD_CFLAGS_32 := $(filter-out -mfentry,$(KBUILD_CFLAGS_32))
 KBUILD_CFLAGS_32 += -m32 -msoft-float -mregparm=0 -fpic
+KBUILD_CFLAGS_32 += $(call cc-option, -fno-stack-protector)
+KBUILD_CFLAGS_32 += $(call cc-option, -foptimize-sibling-calls)
+KBUILD_CFLAGS_32 += -fno-omit-frame-pointer
 $(vdso32-images:%=$(obj)/%.dbg): KBUILD_CFLAGS = $(KBUILD_CFLAGS_32)
 
 $(vdso32-images:%=$(obj)/%.dbg): $(obj)/vdso32-%.so.dbg: FORCE \