diff options
| -rw-r--r-- | arch/arm/boot/compressed/Makefile | 3 | ||||
| -rw-r--r-- | arch/arm/boot/compressed/head.S | 19 |
2 files changed, 18 insertions, 4 deletions
diff --git a/arch/arm/boot/compressed/Makefile b/arch/arm/boot/compressed/Makefile index 0c74a6fab952..4867647b9796 100644 --- a/arch/arm/boot/compressed/Makefile +++ b/arch/arm/boot/compressed/Makefile @@ -104,6 +104,9 @@ endif ccflags-y := -fpic -fno-builtin asflags-y := -Wa,-march=all +# Supply kernel BSS size to the decompressor via a linker symbol. +KBSS_SZ = $(shell size $(obj)/../../../../vmlinux | awk 'END{print $$3}') +LDFLAGS_vmlinux = --defsym _kernel_bss_size=$(KBSS_SZ) # Supply ZRELADDR to the decompressor via a linker symbol. ifneq ($(CONFIG_AUTO_ZRELADDR),y) LDFLAGS_vmlinux += --defsym zreladdr=$(ZRELADDR) diff --git a/arch/arm/boot/compressed/head.S b/arch/arm/boot/compressed/head.S index 3ce5738ddb98..ba5c552f8c69 100644 --- a/arch/arm/boot/compressed/head.S +++ b/arch/arm/boot/compressed/head.S @@ -248,6 +248,18 @@ restart: adr r0, LC0 mov r8, r6 @ use the appended device tree + /* + * Make sure that the DTB doesn't end up in the final + * kernel's .bss area. To do so, we adjust the decompressed + * kernel size to compensate if that .bss size is larger + * than the relocated code. + */ + ldr r5, =_kernel_bss_size + adr r1, wont_overwrite + sub r1, r6, r1 + subs r1, r5, r1 + addhi r9, r9, r1 + /* Get the dtb's size */ ldr r5, [r6, #4] #ifndef __ARMEB__ @@ -276,15 +288,14 @@ dtb_check_done: * 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 <= current position (pc) -> OK + * r4 + image length <= address of wont_overwrite -> OK */ add r10, r10, #16384 cmp r4, r10 bhs wont_overwrite add r10, r4, r9 - ARM( cmp r10, pc ) - THUMB( mov lr, pc ) - THUMB( cmp r10, lr ) + adr r9, wont_overwrite + cmp r10, r9 bls wont_overwrite /* |