[PATCH AUTOSEL 6.6 05/58] s390/boot: Compile all files with the same march flag

Sasha Levin
2024-10-04T18:25:13Z

From: Heiko Carstens <hca@linux.ibm.com>

[ Upstream commit fccb175bc89a0d37e3ff513bb6bf1f73b3a48950 ]

Only a couple of files of the decompressor are compiled with the
minimum architecture level. This is problematic for potential function
calls between compile units, especially if a target function is within
a compile until compiled for a higher architecture level, since that
may lead to an unexpected operation exception.

Therefore compile all files of the decompressor for the same (minimum)
architecture level.

Reviewed-by: Sven Schnelle <svens@linux.ibm.com>
Signed-off-by: Heiko Carstens <hca@linux.ibm.com>
Signed-off-by: Sasha Levin <sashal@kernel.org>
---
arch/s390/boot/Makefile | 19 +++++--------------
1 file changed, 5 insertions(+), 14 deletions(-)

diff --git a/arch/s390/boot/Makefile b/arch/s390/boot/Makefile
index c7c81e5f92189..e4def3a6c6cca 100644
--- a/arch/s390/boot/Makefile
+++ b/arch/s390/boot/Makefile
@@ -9,11 +9,8 @@ UBSAN_SANITIZE := n
KASAN_SANITIZE := n
KCSAN_SANITIZE := n

-KBUILD_AFLAGS := $(KBUILD_AFLAGS_DECOMPRESSOR)
-KBUILD_CFLAGS := $(KBUILD_CFLAGS_DECOMPRESSOR)
-
#
-# Use minimum architecture for als.c to be able to print an error
+# Use minimum architecture level so it is possible to print an error
# message if the kernel is started on a machine which is too old
#
ifndef CONFIG_CC_IS_CLANG
@@ -22,16 +19,10 @@ else
CC_FLAGS_MARCH_MINIMUM := -march=z10
endif

-ifneq ($(CC_FLAGS_MARCH),$(CC_FLAGS_MARCH_MINIMUM))
-AFLAGS_REMOVE_head.o += $(CC_FLAGS_MARCH)
-AFLAGS_head.o += $(CC_FLAGS_MARCH_MINIMUM)
-AFLAGS_REMOVE_mem.o += $(CC_FLAGS_MARCH)
-AFLAGS_mem.o += $(CC_FLAGS_MARCH_MINIMUM)
-CFLAGS_REMOVE_als.o += $(CC_FLAGS_MARCH)
-CFLAGS_als.o += $(CC_FLAGS_MARCH_MINIMUM)
-CFLAGS_REMOVE_sclp_early_core.o += $(CC_FLAGS_MARCH)
-CFLAGS_sclp_early_core.o += $(CC_FLAGS_MARCH_MINIMUM)
-endif
+KBUILD_AFLAGS := $(filter-out $(CC_FLAGS_MARCH),$(KBUILD_AFLAGS_DECOMPRESSOR))
+KBUILD_CFLAGS := $(filter-out $(CC_FLAGS_MARCH),$(KBUILD_CFLAGS_DECOMPRESSOR))
+KBUILD_AFLAGS += $(CC_FLAGS_MARCH_MINIMUM)
+KBUILD_CFLAGS += $(CC_FLAGS_MARCH_MINIMUM)

CFLAGS_sclp_early_core.o += -I$(srctree)/drivers/s390/char

--
2.43.0