@@ -4,6 +4,7 @@
#include <asm/boot.h>
#include <asm/cpufeature.h>
#include <asm/io.h>
+#include <asm/memory.h>
#include <asm/mmu_context.h>
#include <asm/neon.h>
#include <asm/ptrace.h>
@@ -48,6 +49,8 @@
*/
#define EFI_FDT_ALIGN SZ_2M /* used by allocate_new_fdt_and_exit_boot() */
+#define EFI_KIMG_ALIGN SEGMENT_ALIGN
+
/* on arm64, the FDT may be located anywhere in system RAM */
static inline unsigned long efi_get_max_fdt_addr(unsigned long dram_base)
{
@@ -11,6 +11,7 @@
*/
#include <linux/efi.h>
#include <asm/efi.h>
+#include <asm/memory.h>
#include <asm/sections.h>
#include <asm/sysreg.h>
@@ -81,9 +82,10 @@ efi_status_t handle_kernel_image(efi_system_table_t *sys_table_arg,
/*
* If CONFIG_DEBUG_ALIGN_RODATA is not set, produce a
* displacement in the interval [0, MIN_KIMG_ALIGN) that
- * is a multiple of the minimal segment alignment (SZ_64K)
+ * doesn't violate this kernel's de-facto alignment
+ * constraints.
*/
- u32 mask = (MIN_KIMG_ALIGN - 1) & ~(SZ_64K - 1);
+ u32 mask = (MIN_KIMG_ALIGN - 1) & ~(EFI_KIMG_ALIGN - 1);
u32 offset = !IS_ENABLED(CONFIG_DEBUG_ALIGN_RODATA) ?
(phys_seed >> 32) & mask : TEXT_OFFSET;
The EFI stub is intimately coupled with the kernel, and takes advantage of this by relocating the kernel at a weaker alignment than the documented boot protocol mandates. However, it does so by assuming it can align the kernel to the segment alignment, and assumes that this is 64K. In subsequent patches, we'll have to consider other details to determine this de-facto alignment constraint. This patch adds a new EFI_KIMG_ALIGN definition that will track the kernel's de-facto alignment requirements. Subsequent patches will modify this as required. Signed-off-by: Mark Rutland <mark.rutland@arm.com> Cc: Ard Biesheuvel <ard.biesheuvel@linaro.org> Cc: Catalin Marinas <catalin.marinas@arm.com> Cc: James Morse <james.morse@arm.com> Cc: Laura Abbott <labbott@redhat.com> Cc: Matt Fleming <matt@codeblueprint.co.uk> Cc: Will Deacon <will.deacon@arm.com> --- arch/arm64/include/asm/efi.h | 3 +++ drivers/firmware/efi/libstub/arm64-stub.c | 6 ++++-- 2 files changed, 7 insertions(+), 2 deletions(-)