To be able to cross build QEMU itself we need to include a few more
libraries. These are only available in Debian's unstable ports repo
for now so we need:

  - a debian-sid base image with a few tools
  - tweak the riscv64 image to use it
  - add the minimal libs needed to build QEMU (glib/pixman)

The result works but is not as clean as using build-dep to bring in
more dependencies. However sid is by definition a shifting pile of
sand and by keeping the list of libs minimal we reduce the chance of
having an image we can't build. It's good enough for a basic cross
build test.

Signed-off-by: Alex Bennée <alex.bennee@linaro.org>
Cc: Richard Henderson <richard.henderson@linaro.org>
Cc: "Daniel P. Berrangé" <berrange@redhat.com>
---
 tests/docker/Makefile.include                 |  5 ++-
 .../dockerfiles/debian-riscv64-cross.docker   | 15 ++++++---
 tests/docker/dockerfiles/debian-sid.docker    | 33 +++++++++++++++++++
 3 files changed, 46 insertions(+), 7 deletions(-)
 create mode 100644 tests/docker/dockerfiles/debian-sid.docker

diff --git a/tests/docker/Makefile.include b/tests/docker/Makefile.include
index ff5d732889..df56796405 100644
--- a/tests/docker/Makefile.include
+++ b/tests/docker/Makefile.include
@@ -11,7 +11,7 @@ HOST_ARCH = $(if $(ARCH),$(ARCH),$(shell uname -m))
 DOCKER_SUFFIX := .docker
 DOCKER_FILES_DIR := $(SRC_PATH)/tests/docker/dockerfiles
 # we don't run tests on intermediate images (used as base by another image)
-DOCKER_PARTIAL_IMAGES := debian10 debian11 debian-bootstrap empty
+DOCKER_PARTIAL_IMAGES := debian10 debian11 debian-sid debian-bootstrap empty
 DOCKER_IMAGES := $(sort $(notdir $(basename $(wildcard $(DOCKER_FILES_DIR)/*.docker))))
 DOCKER_TARGETS := $(patsubst %,docker-image-%,$(DOCKER_IMAGES))
 # Use a global constant ccache directory to speed up repetitive builds
@@ -141,7 +141,7 @@ docker-image-debian-mips64-cross: docker-image-debian10
 docker-image-debian-mips64el-cross: docker-image-debian10
 docker-image-debian-mipsel-cross: docker-image-debian10
 docker-image-debian-ppc64el-cross: docker-image-debian10
-docker-image-debian-riscv64-cross: docker-image-debian10
+docker-image-debian-riscv64-cross: docker-image-debian-sid
 docker-image-debian-s390x-cross: docker-image-debian10
 docker-image-debian-sh4-cross: docker-image-debian10
 docker-image-debian-sparc64-cross: docker-image-debian10
@@ -180,7 +180,6 @@ DOCKER_PARTIAL_IMAGES += debian-arm64-test-cross
 DOCKER_PARTIAL_IMAGES += debian-powerpc-test-cross
 DOCKER_PARTIAL_IMAGES += debian-hppa-cross
 DOCKER_PARTIAL_IMAGES += debian-m68k-cross debian-mips64-cross
-DOCKER_PARTIAL_IMAGES += debian-riscv64-cross
 DOCKER_PARTIAL_IMAGES += debian-sh4-cross debian-sparc64-cross
 DOCKER_PARTIAL_IMAGES += debian-tricore-cross
 DOCKER_PARTIAL_IMAGES += debian-xtensa-cross
diff --git a/tests/docker/dockerfiles/debian-riscv64-cross.docker b/tests/docker/dockerfiles/debian-riscv64-cross.docker
index 2bbff19772..0f7e5e010e 100644
--- a/tests/docker/dockerfiles/debian-riscv64-cross.docker
+++ b/tests/docker/dockerfiles/debian-riscv64-cross.docker
@@ -1,12 +1,19 @@
 #
 # Docker cross-compiler target
 #
-# This docker target builds on the debian Buster base image.
+# This docker target builds on the Debian Sid (with ports) base image.
 #
-FROM qemu/debian10
+FROM qemu/debian-sid
 
+RUN dpkg --add-architecture riscv64
 RUN apt update && \
     DEBIAN_FRONTEND=noninteractive eatmydata \
     apt install -y --no-install-recommends \
-        gcc-riscv64-linux-gnu \
-        libc6-dev-riscv64-cross
+         gcc-riscv64-linux-gnu \
+         libc6-dev-riscv64-cross \
+         libglib2.0-dev:riscv64 \
+         libpixman-1-dev:riscv64
+
+# Specify the cross prefix for this image (see tests/docker/common.rc)
+ENV QEMU_CONFIGURE_OPTS --cross-prefix=riscv64-linux-gnu-
+ENV DEF_TARGET_LIST riscv64-softmmu,riscv64-linux-user
diff --git a/tests/docker/dockerfiles/debian-sid.docker b/tests/docker/dockerfiles/debian-sid.docker
new file mode 100644
index 0000000000..cb2fdf0d4f
--- /dev/null
+++ b/tests/docker/dockerfiles/debian-sid.docker
@@ -0,0 +1,33 @@
+#
+# Docker sid/ports base packages
+#
+# This docker target uses the current unstable version of Debian as
+# a base for building QEMU for architectures yet to have an official
+# port.
+#
+# On its own you can't build much but the docker-foo-cross targets
+# build on top of the base debian image.
+#
+FROM docker.io/library/debian:sid-slim
+
+# Add ports
+RUN apt update && \
+    DEBIAN_FRONTEND=noninteractive apt install -yy  eatmydata
+RUN DEBIAN_FRONTEND=noninteractive eatmydata \
+    apt install -yy debian-ports-archive-keyring
+
+RUN echo "deb http://ftp.ports.debian.org/debian-ports/ sid main" >> /etc/apt/sources.list
+
+# Duplicate deb line as deb-src
+RUN cat /etc/apt/sources.list | sed "s/^deb\ /deb-src /" >> /etc/apt/sources.list
+
+# Install common build utilities
+RUN DEBIAN_FRONTEND=noninteractive eatmydata \
+    apt upgrade -yy
+RUN DEBIAN_FRONTEND=noninteractive eatmydata apt install -yy \
+    binutils \
+    dpkg-dev \
+    make \
+    ninja-build \
+    python3 \
+    pkg-config
-- 
2.30.2