[pbs-devel] [PATCH proxmox-backup-restore-image 9/9] add debug initramfs as seperate package
Thomas Lamprecht
t.lamprecht at proxmox.com
Thu May 6 20:07:18 CEST 2021
On 06.05.21 17:26, Stefan Reiter wrote:
> "proxmox-backup-restore-image-debug", containing only the debug
> initramfs, so depends on the base "proxmox-backup-restore-image" for the
> kernel.
>
> Adapt the init-shim to start an agetty on ttyS1, which the host
> can use to connect to a root shell for debugging, and use
> create_dir_all, since some debug packages seem to create /sys and /proc
> as empty dirs already.
>
> The build_initramfs.sh script is modified to include dependency
> resolution via apt-rdepends, so debug packages like agetty (util-linux),
> busybox and gdb can easily be added. This now builds both the regular
> and the debug binary at once, to avoid downloading shared packages
> twice.
>
> Signed-off-by: Stefan Reiter <s.reiter at proxmox.com>
> ---
>
> The updated build_initramfs script should also make further additions to the
> initrd easier, e.g. adding lvm and zfs tooling if necessary.
>
> Makefile | 13 +++--
> debian/control | 10 +++-
> ...proxmox-backup-restore-image-debug.install | 1 +
> ...ckup-restore-image-debug.lintian-overrides | 2 +
> ...roxmox-backup-restore-image-debug.triggers | 1 +
> src/Makefile | 5 +-
> src/build_initramfs.sh | 55 +++++++++++++------
> src/init-shim-rs/src/main.rs | 46 +++++++++++++++-
> 8 files changed, 106 insertions(+), 27 deletions(-)
> create mode 100644 debian/proxmox-backup-restore-image-debug.install
> create mode 100644 debian/proxmox-backup-restore-image-debug.lintian-overrides
> create mode 100644 debian/proxmox-backup-restore-image-debug.triggers
>
> diff --git a/Makefile b/Makefile
> index d11ac3e..92aa791 100644
> --- a/Makefile
> +++ b/Makefile
> @@ -2,11 +2,14 @@ include /usr/share/dpkg/pkg-info.mk
> include /usr/share/dpkg/architecture.mk
>
> PACKAGE=proxmox-backup-restore-image
> +PACKAGE_DBG=proxmox-backup-restore-image-debug
>
> BUILDDIR=${PACKAGE}-${DEB_VERSION_UPSTREAM_REVISION}
>
> DEB=${PACKAGE}_${DEB_VERSION}_${DEB_BUILD_ARCH}.deb
> DSC=${PACKAGE}_${DEB_VERSION}.dsc
> +DEB_DBG=${PACKAGE_DBG}_${DEB_VERSION}_${DEB_BUILD_ARCH}.deb
> +DSC_DBG=${PACKAGE_DBG}_${DEB_VERSION}.dsc
>
multiple source control files do not really make sense. There's only one source
per d/control instance (normally per repo) for Debians POV...
> all: deb
>
> @@ -32,21 +35,23 @@ ${BUILDDIR}: submodules.prepared
> deb: ${DEB}
> ${DEB}: ${BUILDDIR}
> cd ${BUILDDIR}; dpkg-buildpackage -b -us -uc
> - lintian ${DEB}
> + lintian ${DEB} ${DEB_DBG}
> +${DEB_DBG}: ${DEB}
>
> .PHONY: dsc
> dsc: ${DSC}
> ${DSC}: ${BUILDDIR}
> cd ${BUILDDIR}; dpkg-buildpackage -S -us -uc -d
> - lintian ${DSC}
> + lintian ${DSC} ${DSC_DBG}
> +${DSC_DBG}: ${DSC}
>
> .PHONY: dinstall
> dinstall: deb
> - dpkg -i ${DEB}
> + dpkg -i ${DEB} ${DEB_DBG}
>
> .PHONY: upload
> upload: ${DEB}
> - tar cf - ${DEB} | ssh -X repoman at repo.proxmox.com upload --product pbs,pve --dist buster
> + tar cf - ${DEB} ${DEB_DBG} | ssh -X repoman at repo.proxmox.com upload --product pbs,pve --dist buster
>
> .PHONY: clean
> clean:
> diff --git a/debian/control b/debian/control
> index 5b50392..b87c903 100644
> --- a/debian/control
> +++ b/debian/control
> @@ -2,7 +2,8 @@ Source: proxmox-backup-restore-image
> Section: admin
> Priority: optional
> Maintainer: Proxmox Support Team <support at proxmox.com>
> -Build-Depends: asciidoc-base,
> +Build-Depends: apt-rdepends,
> + asciidoc-base,
> automake,
> bc,
> bison,
> @@ -34,3 +35,10 @@ Description: Kernel/initramfs images for Proxmox Backup single-file restore.
> Preconfigured images used as base for single file restore of Proxmox Backup
> Server snapshots. Not really useful on their own, so best used together with
> the proxmox-backup-file-restore package, which provide the actual tools.
> +
> +Package: proxmox-backup-restore-image-debug
> +Architecture: amd64
> +Depends: proxmox-backup-restore-image
> +Description: Debug initramfs image for Proxmox Backup single-file restore.
> + Not required for production use, only useful for manual inspection of file
> + restore VMs. Includes busybox and gdb.
> diff --git a/debian/proxmox-backup-restore-image-debug.install b/debian/proxmox-backup-restore-image-debug.install
> new file mode 100644
> index 0000000..02ffb49
> --- /dev/null
> +++ b/debian/proxmox-backup-restore-image-debug.install
> @@ -0,0 +1 @@
> +build/initramfs/initramfs-debug.img /usr/lib/x86_64-linux-gnu/proxmox-backup/file-restore/
> diff --git a/debian/proxmox-backup-restore-image-debug.lintian-overrides b/debian/proxmox-backup-restore-image-debug.lintian-overrides
> new file mode 100644
> index 0000000..ad59aad
> --- /dev/null
> +++ b/debian/proxmox-backup-restore-image-debug.lintian-overrides
> @@ -0,0 +1,2 @@
> +missing-depends-on-sensible-utils
> +uses-dpkg-database-directly
> diff --git a/debian/proxmox-backup-restore-image-debug.triggers b/debian/proxmox-backup-restore-image-debug.triggers
> new file mode 100644
> index 0000000..948d898
> --- /dev/null
> +++ b/debian/proxmox-backup-restore-image-debug.triggers
> @@ -0,0 +1 @@
> +activate-noawait proxmox-backup-restore-image-update
> diff --git a/src/Makefile b/src/Makefile
> index 37f385f..a398ea1 100644
> --- a/src/Makefile
> +++ b/src/Makefile
> @@ -9,12 +9,13 @@ SHIM_DIR=init-shim-rs
>
> KERNEL_IMG=${BUILDDIR}/bzImage
> INITRAMFS_IMG=${INITRAMFS_BUILDDIR}/initramfs.img
> +INITRAMFS_IMG_DBG=${INITRAMFS_BUILDDIR}/initramfs-debug.img
>
> CONFIG=config-base
>
> RUST_SRC=$(wildcard ${SHIM_DIR}/**/*.rs) ${SHIM_DIR}/Cargo.toml
>
> -all: ${KERNEL_IMG} ${INITRAMFS_IMG}
> +all: ${KERNEL_IMG} ${INITRAMFS_IMG_DBG}
>
> ${BUILDDIR}.prepared: ${CONFIG}
> rm -rf ${BUILDDIR}
> @@ -54,6 +55,8 @@ ${INITRAMFS_IMG}: ${BUILDDIR}.prepared ${RUST_SRC} build_initramfs.sh
> cd ${SHIM_DIR}; cargo build --release
> sh build_initramfs.sh
>
> +${INITRAMFS_IMG_DBG}: ${INITRAMFS_IMG}
> +
> .PHONY: test-run
> test-run: ${KERNEL_IMG} ${INITRAMFS_IMG}
> # note: this will always fail since /proxmox-restore-daemon is not
> diff --git a/src/build_initramfs.sh b/src/build_initramfs.sh
> index 4efa29b..c4ee95c 100755
> --- a/src/build_initramfs.sh
> +++ b/src/build_initramfs.sh
> @@ -6,29 +6,36 @@ ROOT="root"
> BUILDDIR="build/initramfs"
> INIT="../../init-shim-rs/target/release/init-shim-rs"
>
> -PKGS=" \
> - libc6:amd64 \
> - libgcc1:amd64 \
> - libstdc++6:amd64 \
> - libssl1.1:amd64 \
> - libattr1:amd64 \
> - libacl1:amd64
> -"
> -
> echo "Using build dir: $BUILDDIR"
> rm -rf "$BUILDDIR"
> mkdir -p "$BUILDDIR"
> cd "$BUILDDIR"
> mkdir "$ROOT"
>
> -# add necessary packages to initramfs
> -for pkg in $PKGS; do
> - apt-get download "$pkg"
> - dpkg-deb -x ./*.deb "$ROOT"
> +# adds necessary packages to initramfs build root folder
> +add_pkgs() {
> + DEPS=""
> + for pkg in $1; do
> + LOCAL_DEPS=$(apt-rdepends -f Depends -s Depends "$pkg" | grep -v '^ ')
> + DEPS="$DEPS $LOCAL_DEPS"
> + done
> + # debconf and gcc are unnecessary
> + DEPS=$(echo "$DEPS" |\
> + sed -E 's/debconf(-2\.0)?//' |\
> + sed -E 's/gcc-.{1,2}-base//')
> + apt-get download $DEPS
> + for deb in ./*.deb; do
> + dpkg-deb -x "$deb" "$ROOT"
> + done
> rm ./*.deb
> -done
> +}
>
> -rm -rf ${ROOT:?}/usr/share # contains only docs and debian stuff
> +make_cpio() {
> + fakeroot -- sh -c "
> + cd '$ROOT';
> + find . -print0 | cpio --null -oV --format=newc -F ../$1
> + "
> +}
>
> cp $INIT "$ROOT/init"
> chmod a+x "$ROOT/init" # just to be sure
> @@ -36,7 +43,19 @@ chmod a+x "$ROOT/init" # just to be sure
> # tell daemon it's running in the correct environment
> touch "$ROOT/restore-vm-marker"
>
> -fakeroot -- sh -c "
> - cd '$ROOT';
> - find . -print0 | cpio --null -oV --format=newc -F ../initramfs.img
> +add_pkgs "
> + libstdc++6:amd64 \
> + libssl1.1:amd64 \
> + libacl1:amd64 \
> "
> +rm -rf ${ROOT:?}/usr/share # contains only docs and debian stuff
> +make_cpio "initramfs.img"
> +
> +# add debug helpers for debug initramfs, packages from above are included too
> +add_pkgs "
> + util-linux:amd64 \
> + busybox-static:amd64 \
> + gdb:amd64 \
> +"
> +# leave /usr/share here, it contains necessary stuff for gdb
> +make_cpio "initramfs-debug.img"
> diff --git a/src/init-shim-rs/src/main.rs b/src/init-shim-rs/src/main.rs
> index 89aff7b..641218f 100644
> --- a/src/init-shim-rs/src/main.rs
> +++ b/src/init-shim-rs/src/main.rs
> @@ -1,6 +1,8 @@
> -use anyhow::Error;
> +use anyhow::{bail, Error};
> use std::ffi::CStr;
> use std::fs;
> +use std::path::PathBuf;
> +use std::process::Command;
>
> const URANDOM_MAJ: u64 = 1;
> const URANDOM_MIN: u64 = 9;
> @@ -21,15 +23,54 @@ fn main() {
> do_mknod("/dev/urandom", URANDOM_MAJ, URANDOM_MIN)
> });
>
> + if let Err(err) = run_agetty() {
> + // not fatal
> + println!("[init-shim] debug: agetty start failed: {}", err);
> + }
> +
> let uptime = read_uptime();
> println!("[init-shim] reached daemon start after {:.2}s", uptime);
>
> do_run("/proxmox-restore-daemon");
> }
>
> +fn run_agetty() -> Result<(), Error> {
> + use nix::unistd::{fork, ForkResult};
> +
> + if !PathBuf::from("/sbin/agetty").exists() {
> + bail!("/sbin/agetty not found, probably not running debug mode and safe to ignore");
> + }
> +
> + if !PathBuf::from("/sys/class/tty/ttyS1/device/driver/serial8250").exists() {
> + bail!("ttyS1 device does not exist or is not a 8250");
> + }
> +
> + let dev = fs::read_to_string("/sys/class/tty/ttyS1/dev")?;
> + let (tty_maj, tty_min) = dev.trim().split_at(dev.find(':').unwrap_or(1));
> + do_mknod("/dev/ttyS1", tty_maj.parse()?, tty_min[1..].parse()?)?;
> +
> + match unsafe { fork() } {
> + Ok(ForkResult::Parent { .. }) => {}
> + Ok(ForkResult::Child) => loop {
> + // continue to restart agetty if it exits, this runs in a forked process
> + println!("[init-shim] Spawning new agetty");
> + let res = Command::new("/sbin/agetty")
> + .args(&["-a", "root", "-l", "/bin/busybox", "-o", "sh", "115200", "ttyS1"])
> + .spawn()
> + .unwrap()
> + .wait()
> + .unwrap();
> + println!("[init-shim] agetty exited: {}", res.code().unwrap_or(-1));
> + },
> + Err(err) => println!("fork failed: {}", err),
> + }
> +
> + Ok(())
> +}
> +
> fn do_mount(target: &str, fstype: &str) -> Result<(), Error> {
> use nix::mount::{mount, MsFlags};
> - fs::create_dir(target)?;
> + fs::create_dir_all(target)?;
> let none_type: Option<&CStr> = None;
> mount(
> none_type,
> @@ -63,7 +104,6 @@ fn read_uptime() -> f32 {
>
> fn do_run(cmd: &str) -> ! {
> use std::io::ErrorKind;
> - use std::process::Command;
>
> let spawn_res = Command::new(cmd).env("RUST_BACKTRACE", "1").spawn();
>
>
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