[U-Boot] [PATCH] efi_loader: Rename sections to allow for implicit data

[Alexander Graf <agraf@suse.de>]

Some times gcc may generate data that is then used within code that may
be part of an efi runtime section. That data could be jump tables,
constants or strings.

In order to make sure we catch these, we need to ensure that gcc emits
them into a section that we can relocate together with all the other
efi runtime bits. This only works if the -ffunction-sections and
-fdata-sections flags are passed and the efi runtime functions are
in a section that starts with ".text".

Up to now we had all efi runtime bits in sections that did not
interfere with the normal section naming scheme, but this forces
us to do so. Hence we need to move the efi_loader text/data/rodata
sections before the global *(.text*) catch-all section.

With this patch in place, we should hopefully have an easier time
to extend the efi runtime functionality in the future.

Signed-off-by: Alexander Graf <agraf@suse.de>
---
 arch/arm/config.mk                        |  4 ++--
 arch/arm/cpu/armv8/u-boot.lds             | 24 +++++++++++++--------
 arch/arm/cpu/u-boot.lds                   | 36 ++++++++++++++++++-------------
 arch/arm/mach-zynq/u-boot.lds             | 36 ++++++++++++++++++-------------
 arch/riscv/cpu/ax25/u-boot.lds            | 26 +++++++++++++---------
 arch/sandbox/config.mk                    |  3 +++
 arch/sandbox/cpu/u-boot.lds               |  9 ++++----
 arch/x86/config.mk                        |  2 +-
 arch/x86/cpu/u-boot.lds                   | 32 ++++++++++++++-------------
 board/qualcomm/dragonboard410c/u-boot.lds | 17 +++++++++++++--
 board/qualcomm/dragonboard820c/u-boot.lds | 24 +++++++++++++--------
 board/ti/am335x/u-boot.lds                | 36 ++++++++++++++++++-------------
 include/efi_loader.h                      |  4 ++--
 13 files changed, 154 insertions(+), 99 deletions(-)

diff --git a/arch/arm/config.mk b/arch/arm/config.mk
index efafc69d1b..f25603109e 100644
--- a/arch/arm/config.mk
+++ b/arch/arm/config.mk
@@ -134,11 +134,11 @@ endif
 ifdef CONFIG_ARM64
 OBJCOPYFLAGS += -j .text -j .secure_text -j .secure_data -j .rodata -j .data \
 		-j .u_boot_list -j .rela.dyn -j .got -j .got.plt \
-		-j .binman_sym_table
+		-j .binman_sym_table -j .text_rest
 else
 OBJCOPYFLAGS += -j .text -j .secure_text -j .secure_data -j .rodata -j .hash \
 		-j .data -j .got -j .got.plt -j .u_boot_list -j .rel.dyn \
-		-j .binman_sym_table
+		-j .binman_sym_table -j .text_rest
 endif
 
 # if a dtb section exists we always have to include it
diff --git a/arch/arm/cpu/armv8/u-boot.lds b/arch/arm/cpu/armv8/u-boot.lds
index eb926b3c14..53de80f745 100644
--- a/arch/arm/cpu/armv8/u-boot.lds
+++ b/arch/arm/cpu/armv8/u-boot.lds
@@ -25,6 +25,19 @@ SECTIONS
 	{
 		*(.__image_copy_start)
 		CPUDIR/start.o (.text*)
+	}
+
+	/* This needs to come before *(.text*) */
+	.efi_runtime : {
+                __efi_runtime_start = .;
+		*(.text.efi_runtime*)
+		*(.rodata.efi_runtime*)
+		*(.data.efi_runtime*)
+                __efi_runtime_stop = .;
+	}
+
+	.text_rest :
+	{
 		*(.text*)
 	}
 
@@ -98,17 +111,10 @@ SECTIONS
 
 	. = ALIGN(8);
 
-	.efi_runtime : {
-                __efi_runtime_start = .;
-		*(efi_runtime_text)
-		*(efi_runtime_data)
-                __efi_runtime_stop = .;
-	}
-
 	.efi_runtime_rel : {
                 __efi_runtime_rel_start = .;
-		*(.relaefi_runtime_text)
-		*(.relaefi_runtime_data)
+		*(.rel*.efi_runtime)
+		*(.rel*.efi_runtime.*)
                 __efi_runtime_rel_stop = .;
 	}
 
diff --git a/arch/arm/cpu/u-boot.lds b/arch/arm/cpu/u-boot.lds
index 4157374d21..834dc99554 100644
--- a/arch/arm/cpu/u-boot.lds
+++ b/arch/arm/cpu/u-boot.lds
@@ -43,6 +43,25 @@ SECTIONS
 		*(.__image_copy_start)
 		*(.vectors)
 		CPUDIR/start.o (.text*)
+	}
+
+	/* This needs to come before *(.text*) */
+	.__efi_runtime_start : {
+		*(.__efi_runtime_start)
+	}
+
+	.efi_runtime : {
+		*(.text.efi_runtime*)
+		*(.rodata.efi_runtime*)
+		*(.data.efi_runtime*)
+	}
+
+	.__efi_runtime_stop : {
+		*(.__efi_runtime_stop)
+	}
+
+	.text_rest :
+	{
 		*(.text*)
 	}
 
@@ -136,27 +155,14 @@ SECTIONS
 
 	. = ALIGN(4);
 
-	.__efi_runtime_start : {
-		*(.__efi_runtime_start)
-	}
-
-	.efi_runtime : {
-		*(efi_runtime_text)
-		*(efi_runtime_data)
-	}
-
-	.__efi_runtime_stop : {
-		*(.__efi_runtime_stop)
-	}
-
 	.efi_runtime_rel_start :
 	{
 		*(.__efi_runtime_rel_start)
 	}
 
 	.efi_runtime_rel : {
-		*(.relefi_runtime_text)
-		*(.relefi_runtime_data)
+		*(.rel*.efi_runtime)
+		*(.rel*.efi_runtime.*)
 	}
 
 	.efi_runtime_rel_stop :
diff --git a/arch/arm/mach-zynq/u-boot.lds b/arch/arm/mach-zynq/u-boot.lds
index ec9a0a0161..91c32e89e8 100644
--- a/arch/arm/mach-zynq/u-boot.lds
+++ b/arch/arm/mach-zynq/u-boot.lds
@@ -19,6 +19,25 @@ SECTIONS
 		*(.__image_copy_start)
 		*(.vectors)
 		CPUDIR/start.o (.text*)
+	}
+
+	/* This needs to come before *(.text*) */
+	.__efi_runtime_start : {
+		*(.__efi_runtime_start)
+	}
+
+	.efi_runtime : {
+		*(.text.efi_runtime*)
+		*(.rodata.efi_runtime*)
+		*(.data.efi_runtime*)
+	}
+
+	.__efi_runtime_stop : {
+		*(.__efi_runtime_stop)
+	}
+
+	.text_rest :
+	{
 		*(.text*)
 	}
 
@@ -41,27 +60,14 @@ SECTIONS
 
 	. = ALIGN(4);
 
-	.__efi_runtime_start : {
-		*(.__efi_runtime_start)
-	}
-
-	.efi_runtime : {
-		*(efi_runtime_text)
-		*(efi_runtime_data)
-	}
-
-	.__efi_runtime_stop : {
-		*(.__efi_runtime_stop)
-	}
-
 	.efi_runtime_rel_start :
 	{
 		*(.__efi_runtime_rel_start)
 	}
 
 	.efi_runtime_rel : {
-		*(.relefi_runtime_text)
-		*(.relefi_runtime_data)
+		*(.rel*.efi_runtime)
+		*(.rel*.efi_runtime.*)
 	}
 
 	.efi_runtime_rel_stop :
diff --git a/arch/riscv/cpu/ax25/u-boot.lds b/arch/riscv/cpu/ax25/u-boot.lds
index 1589babf6c..3cc89746b1 100644
--- a/arch/riscv/cpu/ax25/u-boot.lds
+++ b/arch/riscv/cpu/ax25/u-boot.lds
@@ -12,7 +12,20 @@ SECTIONS
 	.text :
 	{
 		arch/riscv/cpu/ax25/start.o	(.text)
-		*(.text)
+	}
+
+	/* This needs to come before *(.text*) */
+	.efi_runtime : {
+                __efi_runtime_start = .;
+		*(.text.efi_runtime*)
+		*(.rodata.efi_runtime*)
+		*(.data.efi_runtime*)
+                __efi_runtime_stop = .;
+	}
+
+	.text_rest :
+	{
+		*(.text*)
 	}
 
 	. = ALIGN(4);
@@ -39,17 +52,10 @@ SECTIONS
 
     . = ALIGN(4);
 
-	.efi_runtime : {
-                __efi_runtime_start = .;
-		*(efi_runtime_text)
-		*(efi_runtime_data)
-                __efi_runtime_stop = .;
-	}
-
 	.efi_runtime_rel : {
                 __efi_runtime_rel_start = .;
-		*(.relaefi_runtime_text)
-		*(.relaefi_runtime_data)
+		*(.rel*.efi_runtime)
+		*(.rel*.efi_runtime.*)
                 __efi_runtime_rel_stop = .;
 	}
 
diff --git a/arch/sandbox/config.mk b/arch/sandbox/config.mk
index 2babcde881..5e7077bfe7 100644
--- a/arch/sandbox/config.mk
+++ b/arch/sandbox/config.mk
@@ -5,6 +5,9 @@ PLATFORM_CPPFLAGS += -D__SANDBOX__ -U_FORTIFY_SOURCE
 PLATFORM_CPPFLAGS += -DCONFIG_ARCH_MAP_SYSMEM
 PLATFORM_LIBS += -lrt
 
+LDFLAGS_FINAL += --gc-sections
+PLATFORM_RELFLAGS += -ffunction-sections -fdata-sections
+
 # Define this to avoid linking with SDL, which requires SDL libraries
 # This can solve 'sdl-config: Command not found' errors
 ifneq ($(NO_SDL),)
diff --git a/arch/sandbox/cpu/u-boot.lds b/arch/sandbox/cpu/u-boot.lds
index 3a6cf55eb9..727bcc3598 100644
--- a/arch/sandbox/cpu/u-boot.lds
+++ b/arch/sandbox/cpu/u-boot.lds
@@ -24,8 +24,9 @@ SECTIONS
 	}
 
 	.efi_runtime : {
-		*(efi_runtime_text)
-		*(efi_runtime_data)
+		*(.text.efi_runtime*)
+		*(.rodata.efi_runtime*)
+		*(.data.efi_runtime*)
 	}
 
 	.__efi_runtime_stop : {
@@ -38,8 +39,8 @@ SECTIONS
 	}
 
 	.efi_runtime_rel : {
-		*(.relefi_runtime_text)
-		*(.relefi_runtime_data)
+		*(.rel*.efi_runtime)
+		*(.rel*.efi_runtime.*)
 	}
 
 	.efi_runtime_rel_stop :
diff --git a/arch/x86/config.mk b/arch/x86/config.mk
index 5f77f98e60..3759d466ad 100644
--- a/arch/x86/config.mk
+++ b/arch/x86/config.mk
@@ -27,7 +27,7 @@ else
 PLATFORM_CPPFLAGS += $(if $(CONFIG_SPL_BUILD),,-fpic) -fno-common -m64
 endif
 
-PLATFORM_RELFLAGS += -ffunction-sections -fvisibility=hidden
+PLATFORM_RELFLAGS += -ffunction-sections -fdata-sections -fvisibility=hidden
 
 PLATFORM_LDFLAGS += -Bsymbolic -Bsymbolic-functions
 PLATFORM_LDFLAGS += -m $(if $(IS_32BIT),elf_i386,elf_x86_64)
diff --git a/arch/x86/cpu/u-boot.lds b/arch/x86/cpu/u-boot.lds
index f0719368ba..fed006deb7 100644
--- a/arch/x86/cpu/u-boot.lds
+++ b/arch/x86/cpu/u-boot.lds
@@ -17,6 +17,21 @@ SECTIONS
 
 	. = CONFIG_SYS_TEXT_BASE;	/* Location of bootcode in flash */
 	__text_start = .;
+
+	.__efi_runtime_start : {
+		*(.__efi_runtime_start)
+	}
+
+	.efi_runtime : {
+		*(.text.efi_runtime*)
+		*(.rodata.efi_runtime*)
+		*(.data.efi_runtime*)
+	}
+
+	.__efi_runtime_stop : {
+		*(.__efi_runtime_stop)
+	}
+
 	.text  : { *(.text*); }
 
 	. = ALIGN(4);
@@ -43,27 +58,14 @@ SECTIONS
 
 	. = ALIGN(4);
 
-	.__efi_runtime_start : {
-		*(.__efi_runtime_start)
-	}
-
-	.efi_runtime : {
-		*(efi_runtime_text)
-		*(efi_runtime_data)
-	}
-
-	.__efi_runtime_stop : {
-		*(.__efi_runtime_stop)
-	}
-
 	.efi_runtime_rel_start :
 	{
 		*(.__efi_runtime_rel_start)
 	}
 
 	.efi_runtime_rel : {
-		*(.relefi_runtime_text)
-		*(.relefi_runtime_data)
+		*(.rel*.efi_runtime)
+		*(.rel*.efi_runtime.*)
 	}
 
 	.efi_runtime_rel_stop :
diff --git a/board/qualcomm/dragonboard410c/u-boot.lds b/board/qualcomm/dragonboard410c/u-boot.lds
index dc3f718b05..fc1bba8cf0 100644
--- a/board/qualcomm/dragonboard410c/u-boot.lds
+++ b/board/qualcomm/dragonboard410c/u-boot.lds
@@ -20,6 +20,19 @@ SECTIONS
 		*(.__image_copy_start)
 		board/qualcomm/dragonboard410c/head.o (.text*)
 		CPUDIR/start.o (.text*)
+	}
+
+	/* This needs to come before *(.text*) */
+	.efi_runtime : {
+                __efi_runtime_start = .;
+		*(.text.efi_runtime*)
+		*(.rodata.efi_runtime*)
+		*(.data.efi_runtime*)
+                __efi_runtime_stop = .;
+	}
+
+	.text_rest :
+	{
 		*(.text*)
 	}
 
@@ -51,8 +64,8 @@ SECTIONS
 
 	.efi_runtime_rel : {
                 __efi_runtime_rel_start = .;
-		*(.relaefi_runtime_text)
-		*(.relaefi_runtime_data)
+		*(.rel*.efi_runtime)
+		*(.rel*.efi_runtime.*)
                 __efi_runtime_rel_stop = .;
 	}
 
diff --git a/board/qualcomm/dragonboard820c/u-boot.lds b/board/qualcomm/dragonboard820c/u-boot.lds
index bcf5738d38..dcf8256cec 100644
--- a/board/qualcomm/dragonboard820c/u-boot.lds
+++ b/board/qualcomm/dragonboard820c/u-boot.lds
@@ -20,6 +20,19 @@ SECTIONS
 		*(.__image_copy_start)
 		board/qualcomm/dragonboard820c/head.o (.text*)
 		CPUDIR/start.o (.text*)
+	}
+
+	/* This needs to come before *(.text*) */
+	.efi_runtime : {
+                __efi_runtime_start = .;
+		*(.text.efi_runtime*)
+		*(.rodata.efi_runtime*)
+		*(.data.efi_runtime*)
+                __efi_runtime_stop = .;
+	}
+
+	.text_rest :
+	{
 		*(.text*)
 	}
 
@@ -42,17 +55,10 @@ SECTIONS
 
 	. = ALIGN(8);
 
-	.efi_runtime : {
-                __efi_runtime_start = .;
-		*(efi_runtime_text)
-		*(efi_runtime_data)
-                __efi_runtime_stop = .;
-	}
-
 	.efi_runtime_rel : {
                 __efi_runtime_rel_start = .;
-		*(.relaefi_runtime_text)
-		*(.relaefi_runtime_data)
+		*(.rel*.efi_runtime)
+		*(.rel*.efi_runtime.*)
                 __efi_runtime_rel_stop = .;
 	}
 
diff --git a/board/ti/am335x/u-boot.lds b/board/ti/am335x/u-boot.lds
index a56cc8216b..03c1d5f73b 100644
--- a/board/ti/am335x/u-boot.lds
+++ b/board/ti/am335x/u-boot.lds
@@ -37,6 +37,25 @@ SECTIONS
 		*(.vectors)
 		CPUDIR/start.o (.text*)
 		board/ti/am335x/built-in.o (.text*)
+	}
+
+	/* This needs to come before *(.text*) */
+	.__efi_runtime_start : {
+		*(.__efi_runtime_start)
+	}
+
+	.efi_runtime : {
+		*(.text.efi_runtime*)
+		*(.rodata.efi_runtime*)
+		*(.data.efi_runtime*)
+	}
+
+	.__efi_runtime_stop : {
+		*(.__efi_runtime_stop)
+	}
+
+	.text_rest :
+	{
 		*(.text*)
 	}
 
@@ -59,27 +78,14 @@ SECTIONS
 
 	. = ALIGN(4);
 
-	.__efi_runtime_start : {
-		*(.__efi_runtime_start)
-	}
-
-	.efi_runtime : {
-		*(efi_runtime_text)
-		*(efi_runtime_data)
-	}
-
-	.__efi_runtime_stop : {
-		*(.__efi_runtime_stop)
-	}
-
 	.efi_runtime_rel_start :
 	{
 		*(.__efi_runtime_rel_start)
 	}
 
 	.efi_runtime_rel : {
-		*(.relefi_runtime_text)
-		*(.relefi_runtime_data)
+		*(.rel*.efi_runtime)
+		*(.rel*.efi_runtime.*)
 	}
 
 	.efi_runtime_rel_stop :
diff --git a/include/efi_loader.h b/include/efi_loader.h
index c66252a7dd..d6e1f50e22 100644
--- a/include/efi_loader.h
+++ b/include/efi_loader.h
@@ -398,8 +398,8 @@ static inline int guidcmp(const efi_guid_t *g1, const efi_guid_t *g2)
  * Use these to indicate that your code / data should go into the EFI runtime
  * section and thus still be available when the OS is running
  */
-#define __efi_runtime_data __attribute__ ((section ("efi_runtime_data")))
-#define __efi_runtime __attribute__ ((section ("efi_runtime_text")))
+#define __efi_runtime_data __attribute__ ((section (".data.efi_runtime")))
+#define __efi_runtime __attribute__ ((section (".text.efi_runtime")))
 
 /* Call this with mmio_ptr as the _pointer_ to a pointer to an MMIO region
  * to make it available at runtime */
-- 
2.12.3