From 7828a1eeb2a1dc7a1e5ef96d97aaf341862191a1 Mon Sep 17 00:00:00 2001 From: Ilias Apalodimas Date: Fri, 15 Mar 2024 08:43:51 +0200 Subject: [PATCH] arm: remove redundant section alignments Previous patches cleaning up linker symbols, also merged any explicit . = ALIGN(x); into section definitions -- e.g .bss ALIGN(x) : instead of . = ALIGN(x); . bss : {...} However, if the output address is not specified then one will be chosen for the section. This address will be adjusted to fit the alignment requirement of the output section following the strictest alignment of any input section contained within the output section. So let's get rid of the redundant ALIGN directives when they are not needed. While at add comments for the alignment of __bss_start/end since our C runtime setup assembly assumes that __bss_start - __bss_end will be a multiple of 4/8 for armv7 and armv8 respectively. It's worth noting that the alignment is preserved on .rel.dyn for mach-zynq which was explicitly aligning that section on an 8b boundary instead of 4b one. Reviewed-by: Richard Henderson Signed-off-by: Ilias Apalodimas --- arch/arm/cpu/armv8/u-boot.lds | 9 ++++++--- arch/arm/cpu/u-boot.lds | 8 ++++++-- arch/arm/mach-zynq/u-boot.lds | 4 ++-- 3 files changed, 14 insertions(+), 7 deletions(-) diff --git a/arch/arm/cpu/armv8/u-boot.lds b/arch/arm/cpu/armv8/u-boot.lds index 147a6e8028..857f44412e 100644 --- a/arch/arm/cpu/armv8/u-boot.lds +++ b/arch/arm/cpu/armv8/u-boot.lds @@ -115,7 +115,7 @@ SECTIONS KEEP(*(SORT(__u_boot_list*))); } - .efi_runtime_rel ALIGN(8) : { + .efi_runtime_rel : { __efi_runtime_rel_start = .; *(.rel*.efi_runtime) *(.rel*.efi_runtime.*) @@ -125,7 +125,7 @@ SECTIONS . = ALIGN(8); __image_copy_end = .; - .rela.dyn ALIGN(8) : { + .rela.dyn : { __rel_dyn_start = .; *(.rela*) __rel_dyn_end = .; @@ -133,7 +133,10 @@ SECTIONS _end = .; - .bss ALIGN(8): { + /* + * arch/arm/lib/crt0_64.S assumes __bss_start - __bss_end % 8 == 0 + */ + .bss ALIGN(8) : { __bss_start = .; *(.bss*) . = ALIGN(8); diff --git a/arch/arm/cpu/u-boot.lds b/arch/arm/cpu/u-boot.lds index 798858e3ed..707b19795f 100644 --- a/arch/arm/cpu/u-boot.lds +++ b/arch/arm/cpu/u-boot.lds @@ -43,7 +43,7 @@ SECTIONS } /* This needs to come before *(.text*) */ - .efi_runtime ALIGN(4) : { + .efi_runtime : { __efi_runtime_start = .; *(.text.efi_runtime*) *(.rodata.efi_runtime*) @@ -146,7 +146,7 @@ SECTIONS KEEP(*(SORT(__u_boot_list*))); } - .efi_runtime_rel ALIGN(4) : { + .efi_runtime_rel : { __efi_runtime_rel_start = .; *(.rel*.efi_runtime) *(.rel*.efi_runtime.*) @@ -156,6 +156,10 @@ SECTIONS . = ALIGN(4); __image_copy_end = .; + /* + * if CONFIG_USE_ARCH_MEMSET is not selected __bss_end - __bss_start + * needs to be a multiple of 4 and we overlay .bss with .rel.dyn + */ .rel.dyn ALIGN(4) : { __rel_dyn_start = .; *(.rel*) diff --git a/arch/arm/mach-zynq/u-boot.lds b/arch/arm/mach-zynq/u-boot.lds index f6c99a8ce2..3e0c96c505 100644 --- a/arch/arm/mach-zynq/u-boot.lds +++ b/arch/arm/mach-zynq/u-boot.lds @@ -22,7 +22,7 @@ SECTIONS } /* This needs to come before *(.text*) */ - .efi_runtime ALIGN(4) : { + .efi_runtime : { __efi_runtime_start = .; *(.text.efi_runtime*) *(.rodata.efi_runtime*) @@ -52,7 +52,7 @@ SECTIONS KEEP(*(SORT(__u_boot_list*))); } - .efi_runtime_rel ALIGN(4) : { + .efi_runtime_rel : { __efi_runtime_rel_start = .; *(.rel*.efi_runtime) *(.rel*.efi_runtime.*) -- 2.39.5