anchor.diff:  
   COPY kernel_config /linux/arch/x86/configs/x86_64_defconfig
   COPY kernel_config.debug /linux/debug_config
  +
  +ARG DEBUG=0
   
   RUN if [ $DEBUG -ne "0" ]; then \
       cat /linux/debug_config >> /linux/arch/x86/configs/x86_64_defconfig; \
  
positive.code: 
  # Build aufs tools, do this here as they need kernel headers and to match aufs
  # Fortunately they are built statically linked
  
  # aufs-util 20151116
  ENV AUFS_TOOLS_REPO https://github.com/Distrotech/aufs-util.git
  ENV AUFS_TOOLS_COMMIT b5e7e204036da5e815ddec15a847a03c232771b4
  
  RUN git clone ${AUFS_TOOLS_REPO} && \
      cd /aufs-util && \
      git checkout "$AUFS_TOOLS_COMMIT" && \
      CPPFLAGS="-I/tmp/kernel-headers/include" CFLAGS=$CPPFLAGS LDFLAGS=$CPPFLAGS make && \
      DESTDIR=/tmp/aufs-utils make install && \
      rm -rf /tmp/aufs-utils/usr/lib /tmp/aufs-utils/usr/share && \
  
negative.code:     cd /aufs && \
      git checkout -q "$AUFS_COMMIT"
  
  # aufs-util 20151116
  ENV AUFS_TOOLS_REPO https://github.com/Distrotech/aufs-util.git
  ENV AUFS_TOOLS_COMMIT b5e7e204036da5e815ddec15a847a03c232771b4
  
  # Download aufs tools
  RUN git clone ${AUFS_TOOLS_REPO} && \
      cd /aufs-util && \
      git checkout "$AUFS_TOOLS_COMMIT" 
  
  #BUILD
  # patch kernel with aufs
  RUN cd /linux && \
      cp -r /aufs/Documentation /linux && \
  