From d5cbd80e302dfea59726c44c56ab7957f822409f Mon Sep 17 00:00:00 2001 From: Nathan Chancellor Date: Thu, 25 Mar 2021 17:04:34 -0700 Subject: [PATCH] x86/boot: Add $(CLANG_FLAGS) to compressed KBUILD_CFLAGS When cross compiling x86 on an ARM machine with clang, there are several errors along the lines of: arch/x86/include/asm/string_64.h:27:10: error: invalid output constraint '=&c' in asm This happens because the compressed boot Makefile reassigns KBUILD_CFLAGS and drops the clang flags that set the target architecture ('--target=') and the path to the GNU cross tools ('--prefix='), meaning that the host architecture is targeted. These flags are available as $(CLANG_FLAGS) from the main Makefile so add them to the compressed boot folder's KBUILD_CFLAGS so that cross compiling works as expected. Signed-off-by: Nathan Chancellor Signed-off-by: Borislav Petkov Acked-by: Ard Biesheuvel Link: https://lkml.kernel.org/r/20210326000435.4785-3-nathan@kernel.org --- arch/x86/boot/compressed/Makefile | 1 + 1 file changed, 1 insertion(+) diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile index e0bc3988c3fa..6e5522aebbbd 100644 --- a/arch/x86/boot/compressed/Makefile +++ b/arch/x86/boot/compressed/Makefile @@ -46,6 +46,7 @@ KBUILD_CFLAGS += -D__DISABLE_EXPORTS # Disable relocation relaxation in case the link is not PIE. KBUILD_CFLAGS += $(call as-option,-Wa$(comma)-mrelax-relocations=no) KBUILD_CFLAGS += -include $(srctree)/include/linux/hidden.h +KBUILD_CFLAGS += $(CLANG_FLAGS) # sev-es.c indirectly inludes inat-table.h which is generated during # compilation and stored in $(objtree). Add the directory to the includes so