[PATCH] arm64/efi: efistub: apply __init annotation
From: Ard Biesheuvel <hidden>
Date: 2015-01-12 13:29:51
Also in:
linux-efi
Subsystem:
arm64 port (aarch64 architecture), extensible firmware interface (efi), the rest · Maintainers:
Catalin Marinas, Will Deacon, Ard Biesheuvel, Linus Torvalds
This ensures all stub component are freed when the kernel proper is done booting, by prefixing the names of all ELF sections that have the SHF_ALLOC attribute with ".init". This approach ensures that even implicitly emitted allocated data (like initializer values and string literals) are covered. At the same time, remove some __init annotations in the stub that have now become redundant, and add the __init annotation to handle_kernel_image which will trigger a section mismatch without it. Signed-off-by: Ard Biesheuvel <redacted> --- arch/arm64/kernel/efi-stub.c | 14 +++++++------- drivers/firmware/efi/libstub/Makefile | 15 +++++++++++++++ drivers/firmware/efi/libstub/arm-stub.c | 8 ++++---- drivers/firmware/efi/libstub/efi-stub-helper.c | 2 +- 4 files changed, 27 insertions(+), 12 deletions(-)
diff --git a/arch/arm64/kernel/efi-stub.c b/arch/arm64/kernel/efi-stub.c
index d27dd982ff26..f5374065ad53 100644
--- a/arch/arm64/kernel/efi-stub.c
+++ b/arch/arm64/kernel/efi-stub.c@@ -13,13 +13,13 @@ #include <asm/efi.h> #include <asm/sections.h> -efi_status_t handle_kernel_image(efi_system_table_t *sys_table, - unsigned long *image_addr, - unsigned long *image_size, - unsigned long *reserve_addr, - unsigned long *reserve_size, - unsigned long dram_base, - efi_loaded_image_t *image) +efi_status_t __init handle_kernel_image(efi_system_table_t *sys_table, + unsigned long *image_addr, + unsigned long *image_size, + unsigned long *reserve_addr, + unsigned long *reserve_size, + unsigned long dram_base, + efi_loaded_image_t *image) { efi_status_t status; unsigned long kernel_size, kernel_memsize = 0;
diff --git a/drivers/firmware/efi/libstub/Makefile b/drivers/firmware/efi/libstub/Makefile
index b14bc2b9fb4d..4e7de244c663 100644
--- a/drivers/firmware/efi/libstub/Makefile
+++ b/drivers/firmware/efi/libstub/Makefile@@ -24,3 +24,18 @@ lib-y := efi-stub-helper.o lib-$(CONFIG_EFI_ARMSTUB) += arm-stub.o fdt.o CFLAGS_fdt.o += -I$(srctree)/scripts/dtc/libfdt/ + +# +# arm64 puts the stub in the kernel proper, which will unnecessarily retain all +# code indefinitely unless it is annotated as __init/__initdata/__initconst etc. +# So let's apply the __init annotations at the section level, by prefixing +# the section names directly. This will ensure that even all the inline string +# literals are covered. +# +lib-$(CONFIG_ARM64) := $(addsuffix .init,$(lib-y)) + +OBJCOPYFLAGS := --prefix-alloc-sections=.init +$(obj)/%.o.init: $(obj)/%.o FORCE + $(call if_changed,objcopy) + +.PRECIOUS: $(obj)/%.o
diff --git a/drivers/firmware/efi/libstub/arm-stub.c b/drivers/firmware/efi/libstub/arm-stub.c
index e2432b39b6df..dcae482a9a17 100644
--- a/drivers/firmware/efi/libstub/arm-stub.c
+++ b/drivers/firmware/efi/libstub/arm-stub.c@@ -17,10 +17,10 @@ #include "efistub.h" -static int __init efi_secureboot_enabled(efi_system_table_t *sys_table_arg) +static int efi_secureboot_enabled(efi_system_table_t *sys_table_arg) { - static efi_guid_t const var_guid __initconst = EFI_GLOBAL_VARIABLE_GUID; - static efi_char16_t const var_name[] __initconst = { + static efi_guid_t const var_guid = EFI_GLOBAL_VARIABLE_GUID; + static efi_char16_t const var_name[] = { 'S', 'e', 'c', 'u', 'r', 'e', 'B', 'o', 'o', 't', 0 }; efi_get_variable_t *f_getvar = sys_table_arg->runtime->get_variable;
@@ -164,7 +164,7 @@ efi_status_t handle_kernel_image(efi_system_table_t *sys_table, * for both archictectures, with the arch-specific code provided in the * handle_kernel_image() function. */ -unsigned long __init efi_entry(void *handle, efi_system_table_t *sys_table, +unsigned long efi_entry(void *handle, efi_system_table_t *sys_table, unsigned long *image_addr) { efi_loaded_image_t *image;
diff --git a/drivers/firmware/efi/libstub/efi-stub-helper.c b/drivers/firmware/efi/libstub/efi-stub-helper.c
index e766df60fbfb..2fe195002021 100644
--- a/drivers/firmware/efi/libstub/efi-stub-helper.c
+++ b/drivers/firmware/efi/libstub/efi-stub-helper.c@@ -110,7 +110,7 @@ fail: } -unsigned long __init get_dram_base(efi_system_table_t *sys_table_arg) +unsigned long get_dram_base(efi_system_table_t *sys_table_arg) { efi_status_t status; unsigned long map_size;
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1.8.3.2