forked from wrenn/wrenn
pptx704
6898528096
Switch from the envd /init endpoint pushing host time via syscall to chronyd reading the KVM PTP hardware clock (/dev/ptp0) continuously. This fixes clock drift between init calls and handles snapshot resume gracefully. Changes: - Add clocksource=kvm-clock kernel boot arg - Start chronyd in wrenn-init.sh before tini (PHC /dev/ptp0, makestep 1.0 -1) - Remove clock_settime logic from envd SetData and shouldSetSystemTime - Remove client.Init() clock sync calls from sandbox manager (3 sites) - Remove Init() method from envdclient (no longer needed) - Simplify rootfs scripts: socat/chrony now come from apt in the container image, only envd/wrenn-init/tini are injected by build scripts
44 lines
1.6 KiB
Bash
44 lines
1.6 KiB
Bash
#!/bin/sh
|
|
# wrenn-init: minimal PID 1 init for Firecracker microVMs.
|
|
# Mounts virtual filesystems, starts chronyd for time sync, then execs tini + envd.
|
|
|
|
set -e
|
|
|
|
# Mount essential virtual filesystems if not already mounted.
|
|
mount -t proc proc /proc 2>/dev/null || true
|
|
mount -t sysfs sysfs /sys 2>/dev/null || true
|
|
mount -t devtmpfs devtmpfs /dev 2>/dev/null || true
|
|
mkdir -p /dev/pts /dev/shm
|
|
mount -t devpts devpts /dev/pts 2>/dev/null || true
|
|
mount -t tmpfs tmpfs /dev/shm 2>/dev/null || true
|
|
mount -t tmpfs tmpfs /tmp 2>/dev/null || true
|
|
mount -t tmpfs tmpfs /run 2>/dev/null || true
|
|
mkdir -p /sys/fs/cgroup
|
|
mount -t cgroup2 cgroup2 /sys/fs/cgroup 2>/dev/null || true
|
|
echo "+cpu +memory +io" > /sys/fs/cgroup/cgroup.subtree_control 2>/dev/null || true
|
|
|
|
# Set hostname
|
|
hostname sandbox
|
|
|
|
# Configure DNS resolver.
|
|
echo "nameserver 8.8.8.8" > /etc/resolv.conf
|
|
echo "nameserver 8.8.4.4" >> /etc/resolv.conf
|
|
|
|
# Set a standard PATH so envd and all child processes can find common binaries.
|
|
export PATH=/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin
|
|
|
|
# Write chrony config to sync time from the KVM PTP hardware clock.
|
|
# /dev/ptp0 is a paravirtual clock exposed by KVM — no network required.
|
|
mkdir -p /etc/chrony /run/chrony
|
|
cat > /etc/chrony/chrony.conf <<EOF
|
|
refclock PHC /dev/ptp0 poll 2 dpoll 2
|
|
driftfile /run/chrony/chrony.drift
|
|
makestep 1.0 -1
|
|
EOF
|
|
|
|
# Start chronyd in the background before handing off to tini.
|
|
chronyd -f /etc/chrony/chrony.conf 2>/dev/null || true
|
|
|
|
# Exec tini as PID 1 — it reaps zombie processes and forwards signals to envd.
|
|
exec /sbin/tini -- /usr/local/bin/envd
|