13 files changed, 39 insertions, 11 deletions

diff --git a/arch/arm64/Kconfig b/arch/arm64/Kconfig
index 2cc14cef01bd..3a0a4ce4c751 100644
--- a/arch/arm64/Kconfig
+++ b/arch/arm64/Kconfig
@@ -292,6 +292,9 @@ config CMDLINE_FORCE
           This is useful if you cannot or don't want to change the
           command-line options your boot loader passes to the kernel.
 
+config EFI_STUB
+        bool
+
 config EFI
         bool "UEFI runtime support"
         depends on OF && !CPU_BIG_ENDIAN
@@ -299,6 +302,8 @@ config EFI
         select UCS2_STRING
         select EFI_PARAMS_FROM_FDT
         select EFI_RUNTIME_WRAPPERS
+        select EFI_STUB
+        select EFI_ARMSTUB
         default y
         help
           This option provides support for runtime services provided
diff --git a/arch/arm64/Makefile b/arch/arm64/Makefile
index 8185a913c5ed..5836717d2f66 100644
--- a/arch/arm64/Makefile
+++ b/arch/arm64/Makefile
@@ -48,6 +48,7 @@ core-$(CONFIG_XEN) += arch/arm64/xen/
 core-$(CONFIG_CRYPTO) += arch/arm64/crypto/
 libs-y          := arch/arm64/lib/ $(libs-y)
 libs-y          += $(LIBGCC)
+libs-$(CONFIG_EFI_STUB) += drivers/firmware/efi/libstub/
 
 # Default target when executing plain make
 KBUILD_IMAGE    := Image.gz
diff --git a/arch/arm64/kernel/Makefile b/arch/arm64/kernel/Makefile
index cdaedad3afe5..afaeb734295a 100644
--- a/arch/arm64/kernel/Makefile
+++ b/arch/arm64/kernel/Makefile
@@ -4,8 +4,7 @@
 
 CPPFLAGS_vmlinux.lds    := -DTEXT_OFFSET=$(TEXT_OFFSET)
 AFLAGS_head.o           := -DTEXT_OFFSET=$(TEXT_OFFSET)
-CFLAGS_efi-stub.o       := -DTEXT_OFFSET=$(TEXT_OFFSET) \
-                           -I$(src)/../../../scripts/dtc/libfdt
+CFLAGS_efi-stub.o       := -DTEXT_OFFSET=$(TEXT_OFFSET)
 
 CFLAGS_REMOVE_ftrace.o = -pg
 CFLAGS_REMOVE_insn.o = -pg
diff --git a/arch/arm64/kernel/efi-stub.c b/arch/arm64/kernel/efi-stub.c
index e4999021b07d..1317fef8dde9 100644
--- a/arch/arm64/kernel/efi-stub.c
+++ b/arch/arm64/kernel/efi-stub.c
@@ -13,12 +13,6 @@
 #include <asm/efi.h>
 #include <asm/sections.h>
 
-/* Include shared EFI stub code */
-#include "../../../drivers/firmware/efi/efi-stub-helper.c"
-#include "../../../drivers/firmware/efi/fdt.c"
-#include "../../../drivers/firmware/efi/arm-stub.c"
-
-
 efi_status_t handle_kernel_image(efi_system_table_t *sys_table,
                                  unsigned long *image_addr,
                                  unsigned long *image_size,
diff --git a/arch/x86/boot/compressed/Makefile b/arch/x86/boot/compressed/Makefile
index 0fcd9133790c..7a801a310e37 100644
--- a/arch/x86/boot/compressed/Makefile
+++ b/arch/x86/boot/compressed/Makefile
@@ -33,7 +33,8 @@ VMLINUX_OBJS = $(obj)/vmlinux.lds $(obj)/head_$(BITS).o $(obj)/misc.o \
 $(obj)/eboot.o: KBUILD_CFLAGS += -fshort-wchar -mno-red-zone
 
 ifeq ($(CONFIG_EFI_STUB), y)
-        VMLINUX_OBJS += $(obj)/eboot.o $(obj)/efi_stub_$(BITS).o
+        VMLINUX_OBJS += $(obj)/eboot.o $(obj)/efi_stub_$(BITS).o \
+                                $(objtree)/drivers/firmware/efi/libstub/lib.a
 endif
 
 $(obj)/vmlinux: $(VMLINUX_OBJS) FORCE
diff --git a/arch/x86/boot/compressed/eboot.c b/arch/x86/boot/compressed/eboot.c
index 916bbdd7dd28..3b5c66c8f749 100644
--- a/arch/x86/boot/compressed/eboot.c
+++ b/arch/x86/boot/compressed/eboot.c
@@ -280,8 +280,6 @@ void efi_char16_printk(efi_system_table_t *table, efi_char16_t *str)
         }
 }
 
-#include "../../../../drivers/firmware/efi/efi-stub-helper.c"
-
 static void find_bits(unsigned long mask, u8 *pos, u8 *size)
 {
         u8 first, len;
diff --git a/drivers/firmware/efi/Kconfig b/drivers/firmware/efi/Kconfig
index 588dc47e7075..f712d47f30d8 100644
--- a/drivers/firmware/efi/Kconfig
+++ b/drivers/firmware/efi/Kconfig
@@ -57,6 +57,9 @@ config EFI_PARAMS_FROM_FDT
 config EFI_RUNTIME_WRAPPERS
         bool
 
+config EFI_ARMSTUB
+        bool
+
 endmenu
 
 config UEFI_CPER
diff --git a/drivers/firmware/efi/Makefile b/drivers/firmware/efi/Makefile
index e1096539eedb..a204d1474cec 100644
--- a/drivers/firmware/efi/Makefile
+++ b/drivers/firmware/efi/Makefile
@@ -7,3 +7,4 @@ obj-$(CONFIG_EFI_VARS_PSTORE)		+= efi-pstore.o
 obj-$(CONFIG_UEFI_CPER)                 += cper.o
 obj-$(CONFIG_EFI_RUNTIME_MAP)           += runtime-map.o
 obj-$(CONFIG_EFI_RUNTIME_WRAPPERS)      += runtime-wrappers.o
+obj-$(CONFIG_EFI_STUB)                  += libstub/
diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile
new file mode 100644
index 000000000000..b14bc2b9fb4d
--- /dev/null
+++ b/drivers/firmware/efi/libstub/Makefile
@@ -0,0 +1,26 @@
+#
+# The stub may be linked into the kernel proper or into a separate boot binary,
+# but in either case, it executes before the kernel does (with MMU disabled) so
+# things like ftrace and stack-protector are likely to cause trouble if left
+# enabled, even if doing so doesn't break the build.
+#
+cflags-$(CONFIG_X86_32)         := -march=i386
+cflags-$(CONFIG_X86_64)         := -mcmodel=small
+cflags-$(CONFIG_X86)            += -m$(BITS) -D__KERNEL__ $(LINUX_INCLUDE) -O2 \
+                                   -fPIC -fno-strict-aliasing -mno-red-zone \
+                                   -mno-mmx -mno-sse -DDISABLE_BRANCH_PROFILING
+
+cflags-$(CONFIG_ARM64)          := $(subst -pg,,$(KBUILD_CFLAGS))
+cflags-$(CONFIG_ARM)            := $(subst -pg,,$(KBUILD_CFLAGS)) \
+                                   -fno-builtin -fpic -mno-single-pic-base
+
+KBUILD_CFLAGS                   := $(cflags-y) \
+                                   $(call cc-option,-ffreestanding) \
+                                   $(call cc-option,-fno-stack-protector)
+
+GCOV_PROFILE                    := n
+
+lib-y                           := efi-stub-helper.o
+lib-$(CONFIG_EFI_ARMSTUB)       += arm-stub.o fdt.o
+
+CFLAGS_fdt.o                    += -I$(srctree)/scripts/dtc/libfdt/
diff --git a/drivers/firmware/efi/arm-stub.c b/drivers/firmware/efi/libstub/arm-stub.c
index 480339b6b110..480339b6b110 100644
--- a/drivers/firmware/efi/arm-stub.c
+++ b/drivers/firmware/efi/libstub/arm-stub.c
diff --git a/drivers/firmware/efi/efi-stub-helper.c b/drivers/firmware/efi/libstub/efi-stub-helper.c
index 32d5cca30f49..32d5cca30f49 100644
--- a/drivers/firmware/efi/efi-stub-helper.c
+++ b/drivers/firmware/efi/libstub/efi-stub-helper.c
diff --git a/drivers/firmware/efi/efistub.h b/drivers/firmware/efi/libstub/efistub.h
index 304ab295ca1a..304ab295ca1a 100644
--- a/drivers/firmware/efi/efistub.h
+++ b/drivers/firmware/efi/libstub/efistub.h
diff --git a/drivers/firmware/efi/fdt.c b/drivers/firmware/efi/libstub/fdt.c
index 86d2934840e2..86d2934840e2 100644
--- a/drivers/firmware/efi/fdt.c
+++ b/drivers/firmware/efi/libstub/fdt.c