From 265072ba75d7a931ed0a751d5192220bcc5cc230 Mon Sep 17 00:00:00 2001 From: Daniel Schwierzeck Date: Wed, 29 Oct 2014 17:30:36 +0100 Subject: MIPS: add .padding section to linker script Commit 79fd7e649e287228a1445820a72f7dd33baedb96 MIPS: always keep all sections in u-boot ELF binary. Always keep all sections in u-boot ELF binary. Move all unneeded sections after _end to avoid allocating space in the final binary. Also remove .deadcode section which is now obsolete. removed section .deadcode because the original symptoms were not visible anymore. Unfortuneatly the binutils bug still exists. The size of .rel.dyn section is often bigger than needed for all entries. But objcopy only allocates space as much as required for all reloc entries. Thus there is a gap between the last entry and __rel_dyn_end in u-boot.bin. If u-boot is booted from RAM (e.g. in SPL scenarios) that area could contain garbage data which could lead to CPU exceptions during relocation. Signed-off-by: Gabor Juhos Signed-off-by: Daniel Schwierzeck --- arch/mips/config.mk | 2 +- arch/mips/cpu/u-boot.lds | 18 ++++++++++++++++++ 2 files changed, 19 insertions(+), 1 deletion(-) diff --git a/arch/mips/config.mk b/arch/mips/config.mk index b758116d97..4dc88f4d51 100644 --- a/arch/mips/config.mk +++ b/arch/mips/config.mk @@ -71,4 +71,4 @@ PLATFORM_LDFLAGS += -G 0 -static -n -nostdlib PLATFORM_RELFLAGS += -ffunction-sections -fdata-sections LDFLAGS_FINAL += --gc-sections -pie OBJCOPYFLAGS += -j .text -j .rodata -j .data -j .got -OBJCOPYFLAGS += -j .u_boot_list -j .rel.dyn +OBJCOPYFLAGS += -j .u_boot_list -j .rel.dyn -j .padding diff --git a/arch/mips/cpu/u-boot.lds b/arch/mips/cpu/u-boot.lds index e504ea7544..7d71c11ae4 100644 --- a/arch/mips/cpu/u-boot.lds +++ b/arch/mips/cpu/u-boot.lds @@ -61,6 +61,24 @@ SECTIONS __rel_dyn_end = .; } + .padding : { + /* + * Workaround for a binutils feature (or bug?). + * + * The GNU ld from binutils puts the dynamic relocation + * entries into the .rel.dyn section. Sometimes it + * allocates more dynamic relocation entries than it needs + * and the unused slots are set to R_MIPS_NONE entries. + * + * However the size of the .rel.dyn section in the ELF + * section header does not cover the unused entries, so + * objcopy removes those during stripping. + * + * Create a small section here to avoid that. + */ + LONG(0xFFFFFFFF) + } + _end = .; .bss __rel_dyn_start (OVERLAY) : { -- cgit v1.2.1