After this patch: f4d4ffc03efc kbuild: dtbs_install: new make target was added the kernel tree, Linus Walleij noticed that 'make dtbs' forced a following 'make zImage' to rebuild the entire tree, even though nothing had changed. His report: After this patch a while back I have observed the following behaviour of the kernel build: make zImage make zImage -> incremental build, just relink make zImage make dtbs make zImage -> The whole kernel gets rebuilt So now if I happen to recompile my device trees, I suddenly want the entire zImage to be rebuilt to? It's by definition not changes that affect the kernel build :-( I noticed this because my build scripts calls make dtbs && make zImage, and started to rebuild absolutely everything all the time. To fix this, we make only the dtbs_install target depend on the prepare target. It's needed to make sure KERNELVERSION is calculated prior to installing. Fixes: f4d4ffc03efc: ("kbuild: dtbs_install: new make target") Reported-by: Linus Walleij <linus.walleij@xxxxxxxxxx> Tested-by: Linus Walleij <linus.walleij@xxxxxxxxxx> Signed-off-by: Jason Cooper <jason@xxxxxxxxxxxxxx> --- Note: I've no idea if this is a 100% correct solution or not. I know it's definitely better than what we have currently. If there is another way to guarantee KERNELVERSION is set other than depending on 'prepare', I'd love to hear it. thx, Jason. arch/arm/Makefile | 4 +++- 1 file changed, 3 insertions(+), 1 deletion(-) diff --git a/arch/arm/Makefile b/arch/arm/Makefile index 034a94904d69..ae1c278128f8 100644 --- a/arch/arm/Makefile +++ b/arch/arm/Makefile @@ -312,7 +312,9 @@ $(INSTALL_TARGETS): $(Q)$(MAKE) $(build)=$(boot)/dts MACHINE=$(MACHINE) $(boot)/dts/$@ PHONY += dtbs dtbs_install -dtbs dtbs_install: prepare scripts +dtbs: scripts + $(Q)$(MAKE) $(build)=$(boot)/dts MACHINE=$(MACHINE) $@ +dtbs_install: prepare scripts $(Q)$(MAKE) $(build)=$(boot)/dts MACHINE=$(MACHINE) $@ # We use MRPROPER_FILES and CLEAN_FILES now -- 2.1.3 -- To unsubscribe from this list: send the line "unsubscribe devicetree" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html