collapse kernel build back into one file

Signed-off-by: Tycho Andersen <tycho@docker.com>

projects/kernel-config/Dockerfile

@@ -1,10 +1,32 @@
-ARG source=nosuchimage
+FROM linuxkit/kernel-compile:1b396c221af673757703258159ddc8539843b02b@sha256:6b32d205bfc6407568324337b707d195d027328dbfec554428ea93e7b0a8299b AS kernel-build
-FROM ${source} AS kernel-build
 
 ARG KERNEL_VERSION
 ARG KERNEL_SERIES
+ARG ARCH
+ARG DEBUG
 
+ENV KERNEL_SOURCE=https://www.kernel.org/pub/linux/kernel/v4.x/linux-${KERNEL_VERSION}.tar.xz
+
+RUN curl -fsSL -o linux-${KERNEL_VERSION}.tar.xz ${KERNEL_SOURCE}
+
+RUN cat linux-${KERNEL_VERSION}.tar.xz | tar --absolute-names -xJ &&  mv /linux-${KERNEL_VERSION} /linux
+
+RUN mkdir /config
+COPY kernel_config.* /config/
+COPY makeconfig.sh /config
+
+# Apply local patches
+COPY patches-${KERNEL_SERIES} /patches
 WORKDIR /linux
+RUN set -e && for patch in /patches/*.patch; do \
+        echo "Applying $patch"; \
+        patch -p1 < "$patch"; \
+    done
+
+RUN /config/makeconfig.sh ${ARCH} ${KERNEL_SERIES}
+
+RUN mkdir /out
+RUN printf "KERNEL_SOURCE=${KERNEL_SOURCE}\n" > /out/kernel-source-info
 
 # Kernel
 RUN make -j "$(getconf _NPROCESSORS_ONLN)" KCFLAGS="-fno-pie" && \
@@ -38,9 +60,6 @@ RUN DVER=$(basename $(find /tmp/kernel-modules/lib/modules/ -mindepth 1 -maxdept
          tar cf - -T - | (cd $dir; tar xf -) && \
     ( cd /tmp && tar cf /out/kernel-dev.tar usr/src )
 
-RUN printf "KERNEL_SOURCE=${KERNEL_SOURCE}\n" > /out/kernel-source-info
-
-
 FROM linuxkit/toybox-media:eee3dd4d72cd784801e95b1781e6c4f9d8a5e5eb@sha256:7f940e687164ee2676e11c61705c79f7dd2d144ee87ad17a494848a7045f5f53
 ENTRYPOINT []
 CMD []

projects/kernel-config/Dockerfile.config

@@ -1,12 +0,0 @@
-ARG source=nosuchimage
-FROM ${source}
-
-ARG ARCH
-ARG KERNEL_SERIES
-ARG DEBUG
-
-RUN mkdir /config
-COPY kernel_config.* /config/
-COPY makeconfig.sh /config
-
-RUN /config/makeconfig.sh ${ARCH} ${KERNEL_SERIES}

projects/kernel-config/Dockerfile.source

@@ -1,21 +0,0 @@
-FROM linuxkit/kernel-compile:1b396c221af673757703258159ddc8539843b02b@sha256:6b32d205bfc6407568324337b707d195d027328dbfec554428ea93e7b0a8299b AS kernel-build
-
-ARG KERNEL_VERSION
-ARG KERNEL_SERIES
-
-ENV KERNEL_SOURCE=https://www.kernel.org/pub/linux/kernel/v4.x/linux-${KERNEL_VERSION}.tar.xz
-
-RUN curl -fsSL -o linux-${KERNEL_VERSION}.tar.xz ${KERNEL_SOURCE}
-
-RUN cat linux-${KERNEL_VERSION}.tar.xz | tar --absolute-names -xJ &&  mv /linux-${KERNEL_VERSION} /linux
-
-# Apply local patches
-COPY patches-${KERNEL_SERIES} /patches
-WORKDIR /linux
-RUN set -e && for patch in /patches/*.patch; do \
-        echo "Applying $patch"; \
-        patch -p1 < "$patch"; \
-    done
-
-RUN mkdir /out
-RUN printf "KERNEL_SOURCE=${KERNEL_SOURCE}\n" > /out/kernel-source-info

projects/kernel-config/Makefile

@@ -12,6 +12,7 @@
 HASH?=$(shell git ls-tree HEAD -- ../$(notdir $(CURDIR)) | awk '{print $$3}')
 # Name on Hub
 IMAGE:=kernel
+ARCH?=$(shell if [ "$$(arch)" = "x86_64" ]]; then echo x86; else $$(arch); fi)
 
 .PHONY: check tag push sign
 # Targets:
@@ -33,32 +34,13 @@ sign:
 # Set $3 to "_dbg", to build debug kernels. This defines targets like
 # build_4.9.x_dbg and adds "_dbg" to the hub image name.
 define kernel
-.PHONY: source_$(2)$(3)
+build_$(2)$(3): Dockerfile Makefile $(wildcard patches-$(2)/*) $(wildcard kernel_config.$(2)*) kernel_config.base kernel_config.$(ARCH)
-source_$(2)$(3):
-	@# XXX: intentionally dropping $(3) here, since the source is the same for
-	@# both debug and non-debug builds.
-	docker image inspect linuxkit/$(IMAGE)-source:$(1)$-$(HASH) >/dev/null || \
-		docker build -f Dockerfile.source \
-		--build-arg KERNEL_VERSION=$(1) \
-		--build-arg KERNEL_SERIES=$(2) \
-		--no-cache -t linuxkit/$(IMAGE)-source:$(1)$-$(HASH) .
-
-.PHONY: config_$(2)$(3)
-config_$(2)$(3): source_$(2)
-	docker image inspect linuxkit/$(IMAGE)-config:$(1)$(3)-$(HASH) >/dev/null || \
-		docker build -f Dockerfile.config \
-		--build-arg KERNEL_SERIES=$(2) \
-		--build-arg ARCH=x86 \
-		--build-arg DEBUG=$(3) \
-		--build-arg source=linuxkit/$(IMAGE)-source:$(1)-$(HASH) \
-		--no-cache -t linuxkit/$(IMAGE)-config:$(1)$(3)-$(HASH) .
-
-build_$(2)$(3): Dockerfile.build Makefile $(wildcard patches-$(2)/*) kernel_config-$(2) kernel_config.debug config_$(2)$(3)
 	docker pull linuxkit/$(IMAGE):$(1)$(3)-$(HASH) || \
-		docker build -f Dockerfile.build \
+		docker build \
 			--build-arg KERNEL_VERSION=$(1) \
 			--build-arg KERNEL_SERIES=$(2) \
-			--build-arg source=linuxkit/$(IMAGE)-config:$(1)$(3)-$(HASH) \
+			--build-arg ARCH=$(ARCH) \
+			--build-arg DEBUG=$(3) \
 			--no-cache -t linuxkit/$(IMAGE):$(1)$(3)-$(HASH) .
 
 push_$(2)$(3): build_$(2)$(3)