[PATCH v2.1 4/7] Shrink the rootfs substantially

[Andrew Cooper <andrew.cooper3@xxxxxxxxxx>]

bash, busybox, musl and zlib are all in the base container.

python3 and ncurses are in principle used by bits of Xen, but not in anything
we test in CI.  argp-standlone, curl, dbus, libfdt, libgcc and sudo aren't
used at all (for x86 at least).

libbz2 and libuuid were pulled in transitively before, and need to be included
explicitly now.

Use apk --no-cache to avoid keeping a ~2M package index on disk.  Use apk
upgrade in case there are changes to the base container.

Remove the modules scan on boot.  We don't have or build any (except argo, and
that's handled specially).  This removes a chunk of warnings on boot.

This shrinks the rootfs from ~30M down to ~8M.

Factor out some x86-isms in preparation for ARM64 support.

No practical change.

Signed-off-by: Andrew Cooper <andrew.cooper3@xxxxxxxxxx>
---
CC: Anthony PERARD <anthony.perard@xxxxxxxxxx>
CC: Stefano Stabellini <sstabellini@xxxxxxxxxx>
CC: Michal Orzel <michal.orzel@xxxxxxx>
CC: Doug Goldstein <cardoe@xxxxxxxxxx>
CC: Marek Marczykowski-Górecki <marmarek@xxxxxxxxxxxxxxxxxxxxxx>

v2.1:
 * Extend commit message
 * Use apk upgrade

https://gitlab.com/xen-project/hardware/test-artifacts/-/jobs/9713228239
https://gitlab.com/xen-project/hardware/test-artifacts/-/jobs/9713228242
---
 scripts/alpine-rootfs.sh | 60 +++++++++++++++++++++++-----------------
 1 file changed, 34 insertions(+), 26 deletions(-)

diff --git a/scripts/alpine-rootfs.sh b/scripts/alpine-rootfs.sh
index 75e2f8648ce5..b01de9709d02 100755
--- a/scripts/alpine-rootfs.sh
+++ b/scripts/alpine-rootfs.sh
@@ -4,33 +4,42 @@ set -eu
 
 WORKDIR="${PWD}"
 COPYDIR="${WORKDIR}/binaries"
+UNAME=$(uname -m)
 
-apk update
+apk --no-cache upgrade
 
-# xen runtime deps
-apk add musl
-apk add libgcc
-apk add openrc
-apk add busybox
-apk add sudo
-apk add dbus
-apk add bash
-apk add python3
-apk add zlib
-apk add lzo
-apk add ncurses
-apk add yajl
-apk add libaio
-apk add xz
-apk add util-linux
-apk add argp-standalone
-apk add libfdt
-apk add glib
-apk add pixman
-apk add curl
-apk add udev
-apk add pciutils
-apk add libelf
+PKGS=(
+    # System
+    openrc
+    udev
+    util-linux
+
+    # Xen toolstack runtime deps
+    libbz2
+    libuuid
+    lzo
+    xz
+    yajl
+
+    # QEMU
+    glib
+    libaio
+    pixman
+    )
+
+case $UNAME in
+    x86_64)
+        PKGS+=(
+            # System
+            pciutils
+
+            # QEMU
+            libelf
+            )
+        ;;
+esac
+
+apk add --no-cache "${PKGS[@]}"
 
 # Xen
 cd /
@@ -45,7 +54,6 @@ rc-update add dmesg sysinit
 rc-update add hostname boot
 rc-update add hwclock boot
 rc-update add hwdrivers sysinit
-rc-update add modules boot
 rc-update add killprocs shutdown
 rc-update add mount-ro shutdown
 rc-update add savecache shutdown
-- 
2.39.5