s390/vdso: filter out mno-pic-data-is-text-relative cflag

cmd_vdso_check checks if there are any dynamic relocations in
vdso64.so.dbg. When kernel is compiled with
-mno-pic-data-is-text-relative, R_390_RELATIVE relocs are generated and
this results in kernel build error.

kpatch uses -mno-pic-data-is-text-relative option when building the
kernel to prevent relative addressing between code and data. The flag
avoids relocation error when klp text and data are too far apart

kpatch does not patch vdso code and hence the
mno-pic-data-is-text-relative flag is not essential.

Signed-off-by: Sumanth Korikkar <sumanthk@linux.ibm.com>
Acked-by: Ilya Leoshkevich <iii@linux.ibm.com>
Signed-off-by: Alexander Gordeev <agordeev@linux.ibm.com>

diff --git a/arch/s390/kernel/vdso32/Makefile b/arch/s390/kernel/vdso32/Makefile
index f310e807709d14b12b5a65b0ad907ba99601373c..23e868b79a6c99a8e119f829a923dbc6f81cbffa 100644 (file)
--- a/arch/s390/kernel/vdso32/Makefile
+++ b/arch/s390/kernel/vdso32/Makefile
@@ -19,6 +19,7 @@ KBUILD_AFLAGS_32 := $(filter-out -m64,$(KBUILD_AFLAGS))
 KBUILD_AFLAGS_32 += -m31 -s
 
 KBUILD_CFLAGS_32 := $(filter-out -m64,$(KBUILD_CFLAGS))
+KBUILD_CFLAGS_32 := $(filter-out -mno-pic-data-is-text-relative,$(KBUILD_CFLAGS_32))
 KBUILD_CFLAGS_32 += -m31 -fPIC -shared -fno-common -fno-builtin
 
 LDFLAGS_vdso32.so.dbg += -fPIC -shared -soname=linux-vdso32.so.1 \

diff --git a/arch/s390/kernel/vdso64/Makefile b/arch/s390/kernel/vdso64/Makefile
index 279b3bdf98039954af5924f12ce8c0b5f244cb9c..fc1c6ff8178f59489a8957f8ff6c6538b9d54919 100644 (file)
--- a/arch/s390/kernel/vdso64/Makefile
+++ b/arch/s390/kernel/vdso64/Makefile
@@ -24,6 +24,7 @@ KBUILD_AFLAGS_64 := $(filter-out -m64,$(KBUILD_AFLAGS))
 KBUILD_AFLAGS_64 += -m64
 
 KBUILD_CFLAGS_64 := $(filter-out -m64,$(KBUILD_CFLAGS))
+KBUILD_CFLAGS_64 := $(filter-out -mno-pic-data-is-text-relative,$(KBUILD_CFLAGS_64))
 KBUILD_CFLAGS_64 += -m64 -fPIC -fno-common -fno-builtin
 ldflags-y := -fPIC -shared -soname=linux-vdso64.so.1 \
             --hash-style=both --build-id=sha1 -T