Re: [PATCH v3 5/7] CI: avoid repacking initrd as part of the test job

[Andrew Cooper <andrew.cooper3@xxxxxxxxxx>]

On 11/04/2025 9:32 pm, Marek Marczykowski-Górecki wrote:
> The prerequisite for this is building rootfs.cpio.gz, not only
> initrd.tar.gz. That's a change in the test-artifacts repository in the
> "Rootfs generation" series from Andrew.
>
> Having that, do not repack the whole initrd, but only pack modified
> files and rely on Linux handling of concatenated archives.
> This allows packing just test-related files (which includes the whole
> toolstack), instead of the whole initrd.

It's probably worth saying ", fixed subsequently)" for the toolstack, as
it's the single largest aspect.

> DomU initrd handling is a bit more complicated thing. It's sent to the
> target host as part of the dom0 initrd. For now include prepared domU
> initrd as a whole in dom0's rootfs "overlay", which means compressing it
> (again) each job (this takes 3s). This can be later improved by
> splitting domU initrd into two parts (base + overlay) and concatenate
> them in target dom0 already. For this to be useful, test-artifacts would
> need to provide pre-made double-cpio version too (rootfs.cpio.gz wrapper
> in yet another cpio.gz as boot/domU-initrd).
>
> Since full initrd is not unpacked now when preparing domU (and dom0)
> rootfs, a couple of minor changes are needed to how they are prepared.
> This includes creating whole etc/issue file, instead of modifying
> existing one, and a need to create a couple directories.
>
> Finally, move adding "rc_verbose=yes" to /etc/rc.conf to initrd
> building.

These two paragraphs are a little stale now.  etc/issue has already been
committed, and there's no initd building now I've moved arm into test
artefacts.

However, they're going to need tweaking again if I can get the rootfs
generation working more nicely, so lets hold off for now.

>
> Signed-off-by: Marek Marczykowski-Górecki <marmarek@xxxxxxxxxxxxxxxxxxxxxx>
> ---
> Changes in v3:
> - adjust for Andrew's version of cpio rootfs artifacts
> - don't require double-cpio archive for domU initrd, instead add it via
>   dom0 initrd as plain cpio to avoid re-compressing the same thing
> New in v2
>
> Jobs xilinx-* are untested, as I don't have necessary access.
> ---
>  automation/gitlab-ci/test.yaml                    |  6 +++--
>  automation/scripts/qemu-alpine-x86_64.sh          |  9 +++-----
>  automation/scripts/qemu-smoke-dom0-arm64.sh       |  7 ++----
>  automation/scripts/qemu-smoke-dom0less-arm64.sh   |  7 ++----
>  automation/scripts/qubes-x86-64.sh                | 18 +++++++---------
>  automation/scripts/xilinx-smoke-dom0-x86_64.sh    | 15 ++++++-------
>  automation/scripts/xilinx-smoke-dom0less-arm64.sh | 14 +++++-------
>  7 files changed, 35 insertions(+), 41 deletions(-)

One thing that does matter now is the order of appending archives.

I've reworked this locally to be of the form:

# DomU rootfs
cp ../binaries/rootfs.cpio.gz ../binaries/domU-rootfs.cpio.gz

# test-local configuration
mkdir rootfs
...
find . | cpio -H newc -o | gzip >> ../binaries/domU-rootfs.cpio.gz


This then ends up looking rather more clean in followon patches, where
we end up with:

# Dom0 rootfs
cp ../binaries/ucode.cpio ../binaries/dom0-rootfs.cpio.gz
cat ../binaries/rootfs.cpio.gz >> ../binaries/dom0-rootfs.cpio.gz
cat ../binaries/toolstack.cpio.gz >> ../binaries/dom0-rootfs.cpio.gz
if [[ "${TEST}" == argo ]]; then
    cat ../binaries/argo.cpio.gz >> ../binaries/dom0-rootfs.cpio.gz
fi

# test-local configuration
...
find . | cpio -H newc -o | gzip >> ../binaries/dom0-rootfs.cpio.gz


> diff --git a/automation/scripts/xilinx-smoke-dom0-x86_64.sh 
> b/automation/scripts/xilinx-smoke-dom0-x86_64.sh
> index 4db249530823..52a0e05e3f1b 100755
> --- a/automation/scripts/xilinx-smoke-dom0-x86_64.sh
> +++ b/automation/scripts/xilinx-smoke-dom0-x86_64.sh
> @@ -80,6 +80,7 @@ argo-exec -l -p 28333 -- /bin/echo
>  "
>  copy_dom0_files ()
>  {
> +    mkdir -p root usr/local/lib
>      cp "${WORKDIR}/binaries/xen-argo.ko" "root/"
>      cp -ar "${WORKDIR}/binaries/lib/"* "usr/local/lib/"
>      cp "${WORKDIR}/binaries/argo-exec" "usr/local/bin/"
> @@ -92,9 +93,8 @@ fi
>  # Set up domU rootfs.
>  mkdir -p rootfs
>  cd rootfs
> -tar xzf ../binaries/initrd.tar.gz
>  mkdir proc run srv sys
> -rm var/run
> +mkdir -p etc/local.d
>  echo "#!/bin/sh
>  set -x
>  export LD_LIBRARY_PATH=/usr/local/lib
> @@ -102,23 +102,22 @@ PATH=/usr/local/bin:/usr/local/sbin:\$PATH
>  ${DOMU_CMD}
>  " > etc/local.d/xen.start
>  chmod +x etc/local.d/xen.start
> -echo "rc_verbose=yes" >> etc/rc.conf
>  echo "domU Welcome to Alpine Linux 3.18
>  Kernel \r on an \m (\l)
>  
>  " > etc/issue
>  copy_domU_files
> -find . | cpio -H newc -o | gzip > ../binaries/domU-rootfs.cpio.gz
> +cp ../binaries/initrd.cpio.gz ../binaries/domU-rootfs.cpio.gz

Stray initrd.  Found while reworking.

I'll give the whole lot commit-by-commit full runs, when I'm done tinkering.

~Andrew