[PATCH 4.4 21/30] powerpc/boot: Fix zImage TOC alignment

Greg Kroah-Hartman
2017-03-24T18:12:47Z

From: Michael Ellerman <mpe@ellerman.id.au>

commit 97ee351b50a49717543533cfb85b4bf9d88c9680 upstream.

Recent toolchains force the TOC to be 256 byte aligned. We need to
enforce this alignment in the zImage linker script, otherwise pointers
to our TOC variables (__toc_start) could be incorrect. If the actual
start of the TOC and __toc_start don't have the same value we crash
early in the zImage wrapper.

Suggested-by: Alan Modra <amodra@gmail.com>
Signed-off-by: Michael Ellerman <mpe@ellerman.id.au>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

---
arch/powerpc/boot/zImage.lds.S | 1 +
1 file changed, 1 insertion(+)

--- a/arch/powerpc/boot/zImage.lds.S
+++ b/arch/powerpc/boot/zImage.lds.S
@@ -68,6 +68,7 @@ SECTIONS
}

#ifdef CONFIG_PPC64_BOOT_WRAPPER
+ . = ALIGN(256);
.got :
{
__toc_start = .;