diff options
Diffstat (limited to 'arch/arm/boot')
-rw-r--r-- | arch/arm/boot/compressed/Makefile | 15 | ||||
-rw-r--r-- | arch/arm/boot/compressed/head.S | 36 |
2 files changed, 37 insertions, 14 deletions
diff --git a/arch/arm/boot/compressed/Makefile b/arch/arm/boot/compressed/Makefile index d1d43bd22b9..b5083a36421 100644 --- a/arch/arm/boot/compressed/Makefile +++ b/arch/arm/boot/compressed/Makefile @@ -120,10 +120,23 @@ lib1funcs = $(obj)/lib1funcs.o $(obj)/lib1funcs.S: $(srctree)/arch/$(SRCARCH)/lib/lib1funcs.S FORCE $(call cmd,shipped) +# We need to prevent any GOTOFF relocs being used with references +# to symbols in the .bss section since we cannot relocate them +# independently from the rest at run time. This can be achieved by +# ensuring that no private .bss symbols exist, as global symbols +# always have a GOT entry which is what we need. +# The .data section is already discarded by the linker script so no need +# to bother about it here. +check_for_bad_syms = \ +bad_syms=$$($(CROSS_COMPILE)nm $@ | sed -n 's/^.\{8\} [bc] \(.*\)/\1/p') && \ +[ -z "$$bad_syms" ] || \ + ( echo "following symbols must have non local/private scope:" >&2; \ + echo "$$bad_syms" >&2; rm -f $@; false ) + $(obj)/vmlinux: $(obj)/vmlinux.lds $(obj)/$(HEAD) $(obj)/piggy.$(suffix_y).o \ $(addprefix $(obj)/, $(OBJS)) $(lib1funcs) FORCE $(call if_changed,ld) - @: + @$(check_for_bad_syms) $(obj)/piggy.$(suffix_y): $(obj)/../Image FORCE $(call if_changed,$(suffix_y)) diff --git a/arch/arm/boot/compressed/head.S b/arch/arm/boot/compressed/head.S index 8588da39df5..a5a5df65983 100644 --- a/arch/arm/boot/compressed/head.S +++ b/arch/arm/boot/compressed/head.S @@ -179,15 +179,14 @@ not_angel: bl cache_on restart: adr r0, LC0 - ldmia r0, {r1, r2, r3, r5, r6, r10, r11, r12} - ldr sp, [r0, #32] + ldmia r0, {r1, r2, r3, r6, r10, r11, r12} + ldr sp, [r0, #28] /* * We might be running at a different address. We need * to fix up various pointers. */ sub r0, r0, r1 @ calculate the delta offset - add r5, r5, r0 @ _start add r6, r6, r0 @ _edata add r10, r10, r0 @ inflated kernel size location @@ -220,32 +219,38 @@ restart: adr r0, LC0 /* * Check to see if we will overwrite ourselves. * r4 = final kernel address - * r5 = start of this image * r9 = size of decompressed image * r10 = end of this image, including bss/stack/malloc space if non XIP * We basically want: * r4 - 16k page directory >= r10 -> OK - * r4 + image length <= r5 -> OK + * r4 + image length <= current position (pc) -> OK */ add r10, r10, #16384 cmp r4, r10 bhs wont_overwrite add r10, r4, r9 - cmp r10, r5 + cmp r10, pc bls wont_overwrite /* * Relocate ourselves past the end of the decompressed kernel. - * r5 = start of this image * r6 = _edata * r10 = end of the decompressed kernel * Because we always copy ahead, we need to do it from the end and go * backward in case the source and destination overlap. */ - /* Round up to next 256-byte boundary. */ - add r10, r10, #256 + /* + * Bump to the next 256-byte boundary with the size of + * the relocation code added. This avoids overwriting + * ourself when the offset is small. + */ + add r10, r10, #((reloc_code_end - restart + 256) & ~255) bic r10, r10, #255 + /* Get start of code we want to copy and align it down. */ + adr r5, restart + bic r5, r5, #31 + sub r9, r6, r5 @ size to copy add r9, r9, #31 @ rounded up to a multiple bic r9, r9, #31 @ ... of 32 bytes @@ -260,6 +265,11 @@ restart: adr r0, LC0 /* Preserve offset to relocated code. */ sub r6, r9, r6 +#ifndef CONFIG_ZBOOT_ROM + /* cache_clean_flush may use the stack, so relocate it */ + add sp, sp, r6 +#endif + bl cache_clean_flush adr r0, BSYM(restart) @@ -348,12 +358,11 @@ not_relocated: mov r0, #0 LC0: .word LC0 @ r1 .word __bss_start @ r2 .word _end @ r3 - .word _start @ r5 .word _edata @ r6 .word input_data_end - 4 @ r9 (inflated size location) .word _got_start @ r11 .word _got_end @ ip - .word user_stack_end @ sp + .word .L_user_stack_end @ sp .size LC0, . - LC0 #ifdef CONFIG_ARCH_RPC @@ -1077,8 +1086,9 @@ memdump: mov r12, r0 #endif .ltorg +reloc_code_end: .align .section ".stack", "aw", %nobits -user_stack: .space 4096 -user_stack_end: +.L_user_stack: .space 4096 +.L_user_stack_end: |