From add7490c273650c3aa8012f3e082aa64af86f17c Mon Sep 17 00:00:00 2001
From: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Date: Mon, 23 May 2011 10:24:31 +0200
Subject: [PATCH] [S390] vdso: disable gcov profiling

The concepts of VDSO and gcov-based profiling don't mix: the former
includes kernel-provided code running in userspace, the latter adds
instructions that modify counters in kernel data segments. On s390
this has not been a problem so far due to VDSO code being written in
all-assembler which is exempt from gcov-based profiling. This could
change in the future, so disable profiling excplicitly for VDSO code.

Signed-off-by: Peter Oberparleiter <peter.oberparleiter@de.ibm.com>
Signed-off-by: Martin Schwidefsky <schwidefsky@de.ibm.com>
---
 arch/s390/kernel/vdso32/Makefile | 3 +++
 arch/s390/kernel/vdso64/Makefile | 3 +++
 2 files changed, 6 insertions(+)

diff --git a/arch/s390/kernel/vdso32/Makefile b/arch/s390/kernel/vdso32/Makefile
index d13e8755a8cce..8ad2b34ad1513 100644
--- a/arch/s390/kernel/vdso32/Makefile
+++ b/arch/s390/kernel/vdso32/Makefile
@@ -22,6 +22,9 @@ obj-y += vdso32_wrapper.o
 extra-y += vdso32.lds
 CPPFLAGS_vdso32.lds += -P -C -U$(ARCH)
 
+# Disable gcov profiling for VDSO code
+GCOV_PROFILE := n
+
 # Force dependency (incbin is bad)
 $(obj)/vdso32_wrapper.o : $(obj)/vdso32.so
 
diff --git a/arch/s390/kernel/vdso64/Makefile b/arch/s390/kernel/vdso64/Makefile
index 449352dda9cdb..2a8ddfd12a5b9 100644
--- a/arch/s390/kernel/vdso64/Makefile
+++ b/arch/s390/kernel/vdso64/Makefile
@@ -22,6 +22,9 @@ obj-y += vdso64_wrapper.o
 extra-y += vdso64.lds
 CPPFLAGS_vdso64.lds += -P -C -U$(ARCH)
 
+# Disable gcov profiling for VDSO code
+GCOV_PROFILE := n
+
 # Force dependency (incbin is bad)
 $(obj)/vdso64_wrapper.o : $(obj)/vdso64.so
 
-- 
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