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From: Arnd Bergmann <arnd@arndb.de>
To: Kees Cook <keescook@chromium.org>
Cc: Russell King <linux@arm.linux.org.uk>, linux-kernel@vger.kernel.org,
        Jeffy <jeffy.chen@rock-chips.com>,
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        Laurent Pinchart <laurent.pinchart@ideasonboard.com>,
        Magnus Damm <damm+renesas@opensource.se>,
        linux-arm-kernel@lists.infradead.org
Subject: Re: [PATCH] ARM: fix atags_to_fdt with stack-protector-strong
Date: Fri, 18 Dec 2015 22:09:12 +0100
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On Friday 18 December 2015 13:04:59 Kees Cook wrote:
> +ifeq ($(CONFIG_ARM_ATAG_DTB_COMPAT),y)
> +CFLAGS_atags_to_fdt.o := -fno-stack-protector
> +CFLAGS_fdt.o := -fno-stack-protector
> +CFLAGS_fdt_ro.o := -fno-stack-protector
> +CFLAGS_fdt_rw.o := -fno-stack-protector
> +CFLAGS_fdt_wip.o := -fno-stack-protector
> +endif

I'm pretty sure you don't need the ifeq there, you can simply define those
flags unconditionally.

You can't just add -fno-stack-protector unconditionally, because that
breaks building the kernel with toolchains that are older than stack-protector,
so this should be

CFLAGS_obj.o += $(call cc-option, -fno-stack-protector)

Other than that, the patch looks ok.

	Arnd