Patch "s390/boot: Compile all files with the same march flag" has been added to the 6.11-stable tree

[Sasha Levin <sashal@xxxxxxxxxx>]

This is a note to let you know that I've just added the patch titled

    s390/boot: Compile all files with the same march flag

to the 6.11-stable tree which can be found at:
    http://www.kernel.org/git/?p=linux/kernel/git/stable/stable-queue.git;a=summary

The filename of the patch is:
     s390-boot-compile-all-files-with-the-same-march-flag.patch
and it can be found in the queue-6.11 subdirectory.

If you, or anyone else, feels it should not be added to the stable tree,
please let <stable@xxxxxxxxxxxxxxx> know about it.



commit d4aaa112a50ff5c137f0d72fd5c1cd0c7ee182b8
Author: Heiko Carstens <hca@xxxxxxxxxxxxx>
Date:   Wed Sep 4 11:39:27 2024 +0200

    s390/boot: Compile all files with the same march flag
    
    [ 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@xxxxxxxxxxxxx>
    Signed-off-by: Heiko Carstens <hca@xxxxxxxxxxxxx>
    Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>

diff --git a/arch/s390/boot/Makefile b/arch/s390/boot/Makefile
index 4f476884d3404..f1b2989cc7cca 100644
--- a/arch/s390/boot/Makefile
+++ b/arch/s390/boot/Makefile
@@ -11,11 +11,8 @@ KASAN_SANITIZE := n
 KCSAN_SANITIZE := n
 KMSAN_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
@@ -24,16 +21,10 @@ 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