[PATCH] ARM: kbuild: Fix forced rebuild after 'make dtbs'

[Russell King - ARM Linux]

On Wed, Nov 26, 2014 at 02:57:42PM +0100, Linus Walleij wrote:
> make -f Makefile -j5 ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf-
> KBUILD_OUTPUT=build-u300 u300_defconfig
> make -f Makefile -j5 ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf-
> KBUILD_OUTPUT=build-u300 zImage CONFIG_DEBUG_SECTION_MISMATCH=y
> make -f Makefile -j5 ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf-
> KBUILD_OUTPUT=build-u300 dtbs
> make -f Makefile -j5 ARCH=arm CROSS_COMPILE=arm-linux-gnueabihf-
> KBUILD_OUTPUT=build-u300 zImage CONFIG_DEBUG_SECTION_MISMATCH=y
> 
> -> Rebuilds everything.
> 
> This doesn't occur before the offending commit. So it only happens
> when specifying extra environment variables on the command line.

I suspect if you also provide the CONFIG_DEBUG_SECTION_MISMATCH=y on the
dtbs line, everything will work properly.

The problem is that dtbs line executes a prepare, which I guess rebuilds
the bounds stuff.  So, the dtbs target results in it being rebuilt without
the section mismatch, and then you re-execute a make with it, causing
the bounds stuff to be rebuilt again.

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