Refactor the generic EFI stub entry code so that all the dependencies on
device tree are abstracted and hidden behind a generic efi_boot_kernel()
routine that can also be implemented in other ways. This allows users of
the generic stub to avoid using FDT for passing information to the core
kernel.
Signed-off-by: Ard Biesheuvel <ardb@xxxxxxxxxx>
---
drivers/firmware/efi/libstub/efi-stub.c | 53 +---------------
drivers/firmware/efi/libstub/efistub.h | 7 +--
drivers/firmware/efi/libstub/fdt.c | 64 ++++++++++++++++++--
3 files changed, 63 insertions(+), 61 deletions(-)
diff --git a/drivers/firmware/efi/libstub/efi-stub.c b/drivers/firmware/efi/libstub/efi-stub.c
index 88bdd0a6b488..8715f5a36b92 100644
--- a/drivers/firmware/efi/libstub/efi-stub.c
+++ b/drivers/firmware/efi/libstub/efi-stub.c
@@ -10,7 +10,6 @@
*/
#include <linux/efi.h>
-#include <linux/libfdt.h>
#include <asm/efi.h>
#include "efistub.h"
@@ -130,14 +129,11 @@ efi_status_t __efiapi efi_pe_entry(efi_handle_t handle,
unsigned long image_addr;
unsigned long image_size = 0;
/* addr/point and size pairs for memory management*/
- unsigned long fdt_addr = 0; /* Original DTB */
- unsigned long fdt_size = 0;
char *cmdline_ptr = NULL;
int cmdline_size = 0;
efi_guid_t loaded_image_proto = LOADED_IMAGE_PROTOCOL_GUID;
unsigned long reserve_addr = 0;
unsigned long reserve_size = 0;
- enum efi_secureboot_mode secure_boot;
struct screen_info *si;
efi_properties_table_t *prop_tbl;
@@ -213,38 +209,6 @@ efi_status_t __efiapi efi_pe_entry(efi_handle_t handle,
/* Ask the firmware to clear memory on unclean shutdown */
efi_enable_reset_attack_mitigation();
- secure_boot = efi_get_secureboot();
-
- /*
- * Unauthenticated device tree data is a security hazard, so ignore
- * 'dtb=' unless UEFI Secure Boot is disabled. We assume that secure
- * boot is enabled if we can't determine its state.
- */
- if (!IS_ENABLED(CONFIG_EFI_ARMSTUB_DTB_LOADER) ||
- secure_boot != efi_secureboot_mode_disabled) {
- if (strstr(cmdline_ptr, "dtb="))
- efi_err("Ignoring DTB from command line.\n");
- } else {
- status = efi_load_dtb(image, &fdt_addr, &fdt_size);
-
- if (status != EFI_SUCCESS) {
- efi_err("Failed to load device tree!\n");
- goto fail_free_image;
- }
- }
-
- if (fdt_addr) {
- efi_info("Using DTB from command line\n");
- } else {
- /* Look for a device tree configuration table entry. */
- fdt_addr = (uintptr_t)get_fdt(&fdt_size);
- if (fdt_addr)
- efi_info("Using DTB from configuration table\n");
- }
-
- if (!fdt_addr)
- efi_info("Generating empty DTB\n");
-
efi_load_initrd(image, ULONG_MAX,
efi_get_max_initrd_addr(image_addr));
@@ -288,23 +252,8 @@ efi_status_t __efiapi efi_pe_entry(efi_handle_t handle,
install_memreserve_table();
- status = allocate_new_fdt_and_exit_boot(handle, &fdt_addr, cmdline_ptr,
- fdt_addr, fdt_size);
- if (status != EFI_SUCCESS)
- goto fail_free_fdt;
-
- if (IS_ENABLED(CONFIG_ARM))
- efi_handle_post_ebs_state();
-
- efi_enter_kernel(image_addr, fdt_addr, fdt_totalsize((void *)fdt_addr));
- /* not reached */
-
-fail_free_fdt:
- efi_err("Failed to update FDT and exit boot services\n");
-
- efi_free(fdt_size, fdt_addr);
+ status = efi_boot_kernel(handle, image, image_addr, cmdline_ptr);
-fail_free_image:
efi_free(image_size, image_addr);
efi_free(reserve_size, reserve_addr);
fail_free_screeninfo:
diff --git a/drivers/firmware/efi/libstub/efistub.h b/drivers/firmware/efi/libstub/efistub.h
index 82cff342da05..f65a8a3844b8 100644
--- a/drivers/firmware/efi/libstub/efistub.h
+++ b/drivers/firmware/efi/libstub/efistub.h
@@ -865,11 +865,8 @@ typedef efi_status_t (*efi_exit_boot_map_processing)(
efi_status_t efi_exit_boot_services(void *handle, void *priv,
efi_exit_boot_map_processing priv_func);
-efi_status_t allocate_new_fdt_and_exit_boot(void *handle,
- unsigned long *new_fdt_addr,
- char *cmdline_ptr,
- unsigned long fdt_addr,
- unsigned long fdt_size);
+efi_status_t efi_boot_kernel(void *handle, efi_loaded_image_t *image,
+ unsigned long image_addr, char *cmdline_ptr);
void *get_fdt(unsigned long *fdt_size);
diff --git a/drivers/firmware/efi/libstub/fdt.c b/drivers/firmware/efi/libstub/fdt.c
index a3cd603ea484..8251c9c8463d 100644
--- a/drivers/firmware/efi/libstub/fdt.c
+++ b/drivers/firmware/efi/libstub/fdt.c
@@ -219,17 +219,19 @@ static efi_status_t exit_boot_func(struct efi_boot_memmap *map, void *priv)
* exit_boot_services() call, so the exiting of boot services is very tightly
* tied to the creation of the FDT with the final memory map in it.
*/
-
+static
efi_status_t allocate_new_fdt_and_exit_boot(void *handle,
+ efi_loaded_image_t *image,
unsigned long *new_fdt_addr,
- char *cmdline_ptr,
- unsigned long fdt_addr,
- unsigned long fdt_size)
+ char *cmdline_ptr)
{
unsigned long desc_size;
u32 desc_ver;
efi_status_t status;
+ enum efi_secureboot_mode secure_boot;
struct exit_boot_struct priv;
+ unsigned long fdt_addr = 0;
+ unsigned long fdt_size = 0;
status = efi_alloc_virtmap(&priv.runtime_map, &desc_size, &desc_ver);
if (status != EFI_SUCCESS) {
@@ -237,6 +239,38 @@ efi_status_t allocate_new_fdt_and_exit_boot(void *handle,
return status;
}
+ secure_boot = efi_get_secureboot();
+
+ /*
+ * Unauthenticated device tree data is a security hazard, so ignore
+ * 'dtb=' unless UEFI Secure Boot is disabled. We assume that secure
+ * boot is enabled if we can't determine its state.
+ */
+ if (!IS_ENABLED(CONFIG_EFI_ARMSTUB_DTB_LOADER) ||
+ secure_boot != efi_secureboot_mode_disabled) {
+ if (strstr(cmdline_ptr, "dtb="))
+ efi_err("Ignoring DTB from command line.\n");
+ } else {
+ status = efi_load_dtb(image, &fdt_addr, &fdt_size);
+
+ if (status != EFI_SUCCESS) {
+ efi_err("Failed to load device tree!\n");
+ goto fail;
+ }
+ }
+
+ if (fdt_addr) {
+ efi_info("Using DTB from command line\n");
+ } else {
+ /* Look for a device tree configuration table entry. */
+ fdt_addr = (uintptr_t)get_fdt(&fdt_size);
+ if (fdt_addr)
+ efi_info("Using DTB from configuration table\n");
+ }
+
+ if (!fdt_addr)
+ efi_info("Generating empty DTB\n");
+
efi_info("Exiting boot services...\n");
status = efi_allocate_pages(MAX_FDT_SIZE, new_fdt_addr, ULONG_MAX);
@@ -300,11 +334,33 @@ efi_status_t allocate_new_fdt_and_exit_boot(void *handle,
efi_free(MAX_FDT_SIZE, *new_fdt_addr);
fail:
+ efi_free(fdt_size, fdt_addr);
+
efi_bs_call(free_pool, priv.runtime_map);
return EFI_LOAD_ERROR;
}
+efi_status_t efi_boot_kernel(void *handle, efi_loaded_image_t *image,
+ unsigned long image_addr, char *cmdline_ptr)
+{
+ unsigned long fdt_addr;
+ efi_status_t status;
+
+ status = allocate_new_fdt_and_exit_boot(handle, image, &fdt_addr,
+ cmdline_ptr);
+ if (status != EFI_SUCCESS) {
+ efi_err("Failed to update FDT and exit boot services\n");
+ return status;
+ }
+
+ if (IS_ENABLED(CONFIG_ARM))
+ efi_handle_post_ebs_state();
+
+ efi_enter_kernel(image_addr, fdt_addr, fdt_totalsize((void *)fdt_addr));
+ /* not reached */
+}
+
void *get_fdt(unsigned long *fdt_size)
{
void *fdt;
--
2.35.1
