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 <[email protected]> --- 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; -- 1.8.3.2 -- To unsubscribe from this list: send the line "unsubscribe linux-efi" in the body of a message to [email protected] More majordomo info at http://vger.kernel.org/majordomo-info.html
