From f8d3e5069ac6a3939aa67cc9ae88743966d0357d Mon Sep 17 00:00:00 2001
From: Alexander Egorenkov <egorenar@linux.ibm.com>
Date: Wed, 28 Oct 2020 14:57:37 +0100
Subject: [PATCH] hsavmcore: add dracut modules and systemd services for kdump
 initramfs
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

* Provide a dracut module and a systemd service for Fedora, RHEL and SLES.
* Provide a systemd service for Ubuntu.

Signed-off-by: Alexander Egorenkov <egorenar@linux.ibm.com>
Reviewed-by: Philipp Rudo <prudo@linux.ibm.com>
Acked-by: Jan Höppner <hoeppner@linux.ibm.com>
Signed-off-by: Jan Höppner <hoeppner@linux.ibm.com>
---
 hsavmcore/initramfs/fedora-rhel/README.md     | 147 ++++++++++++++++++
 .../modules.d/99hsavmcore/hsavmcore.service   |  20 +++
 .../modules.d/99hsavmcore/module-setup.sh     |  37 +++++
 .../modules.d/99hsavmcore/setup-fuse.sh       |   3 +
 hsavmcore/initramfs/sles/README.md            | 141 +++++++++++++++++
 .../modules.d/99hsavmcore/hsavmcore.service   |  21 +++
 .../modules.d/99hsavmcore/module-setup.sh     |  47 ++++++
 .../modules.d/99hsavmcore/setup-fuse.sh       |   3 +
 hsavmcore/initramfs/ubuntu/README.md          | 142 +++++++++++++++++
 hsavmcore/initramfs/ubuntu/hsavmcore.service  |  22 +++
 10 files changed, 583 insertions(+)
 create mode 100644 hsavmcore/initramfs/fedora-rhel/README.md
 create mode 100644 hsavmcore/initramfs/fedora-rhel/dracut/modules.d/99hsavmcore/hsavmcore.service
 create mode 100755 hsavmcore/initramfs/fedora-rhel/dracut/modules.d/99hsavmcore/module-setup.sh
 create mode 100644 hsavmcore/initramfs/fedora-rhel/dracut/modules.d/99hsavmcore/setup-fuse.sh
 create mode 100644 hsavmcore/initramfs/sles/README.md
 create mode 100644 hsavmcore/initramfs/sles/dracut/modules.d/99hsavmcore/hsavmcore.service
 create mode 100755 hsavmcore/initramfs/sles/dracut/modules.d/99hsavmcore/module-setup.sh
 create mode 100644 hsavmcore/initramfs/sles/dracut/modules.d/99hsavmcore/setup-fuse.sh
 create mode 100644 hsavmcore/initramfs/ubuntu/README.md
 create mode 100644 hsavmcore/initramfs/ubuntu/hsavmcore.service

diff --git a/hsavmcore/initramfs/fedora-rhel/README.md b/hsavmcore/initramfs/fedora-rhel/README.md
new file mode 100644
index 00000000..81b872c5
--- /dev/null
+++ b/hsavmcore/initramfs/fedora-rhel/README.md
@@ -0,0 +1,147 @@
+
+# Setup
+
+## Configure crashkernel
+
+```shell
+sudo grubby --args "crashkernel=512M" --update-kernel=ALL
+sudo reboot
+```
+
+## Production kernel's root file system
+
+- kdump mounts the production kernel's root file system under **/sysroot**.
+
+## Dependencies
+
+```shell
+sudo dnf install -y fuse fuse-devel systemd-devel
+```
+
+## Build hsavmcore
+
+```shell
+make -C s390-tools/hsavmcore
+```
+
+## Install hsavmcore
+
+```shell
+sudo cp s390-tools/hsavmcore/hsavmcore /usr/sbin/
+```
+
+## Create swap file
+
+```shell
+sudo dd if=/dev/zero of=/var/crash/swap.img bs=1M count=1024
+sudo mkswap /var/crash/swap.img
+```
+
+## Install hsavmcore.conf
+
+### Test configuration
+
+- Doesn't require HSA support
+
+#### HSA cache in file
+
+```shell
+cat <<EOF | sudo tee /etc/hsavmcore.conf
+verbose = 2
+workdir = /sysroot/var/crash
+use_hsa_mem = 0
+mount_debugfs = 1
+hsa_size = 0x1ffff000
+release_hsa = 0
+bind_mount_vmcore = 1
+EOF
+```
+
+#### HSA cache in memory
+
+```shell
+cat <<EOF | sudo tee /etc/hsavmcore.conf
+verbose = 2
+workdir = /sysroot/var/crash
+use_hsa_mem = 1
+mount_debugfs = 1
+hsa_size = 0x1ffff000
+release_hsa = 0
+bind_mount_vmcore = 1
+swap = /sysroot/var/crash/swap.img
+EOF
+```
+
+### Production configuration
+
+- Works only on s390x
+
+#### HSA cache in file
+
+```shell
+cat <<EOF | sudo tee /etc/hsavmcore.conf
+verbose = 2
+workdir = /sysroot/var/crash
+use_hsa_mem = 0
+mount_debugfs = 1
+hsa_size = -1
+release_hsa = 1
+bind_mount_vmcore = 1
+EOF
+```
+
+#### HSA cache in memory
+
+```shell
+cat <<EOF | sudo tee /etc/hsavmcore.conf
+verbose = 2
+workdir = /sysroot/var/crash
+use_hsa_mem = 1
+mount_debugfs = 1
+hsa_size = -1
+release_hsa = 1
+bind_mount_vmcore = 1
+swap = /sysroot/var/crash/swap.img
+EOF
+```
+
+## Install new dracut module
+
+```shell
+sudo cp -r s390-tools/hsavmcore/initramfs/fedora-rhel/dracut/modules.d/99hsavmcore /lib/dracut/modules.d/
+```
+
+## Add the new dracut module as a dependency to the dracut module *kdumpbase*
+
+```shell
+sudo sed -e 's#local _dep="base shutdown"#local _dep="base shutdown hsavmcore"#' \
+         -i /lib/dracut/modules.d/99kdumpbase/module-setup.sh
+```
+
+## Rebuild kdump initramfs
+
+```shell
+sudo kdumpctl rebuild
+```
+
+## Enable swap LVM in kdump
+
+- Required if you want to use a swap device in kdump
+
+```shell
+sudo sed -e 's#^KDUMP_COMMANDLINE_APPEND="\(.*\)"$#KDUMP_COMMANDLINE_APPEND="\1 rd.lvm.lv=rhel/swap"#' \
+         -i /etc/sysconfig/kdump
+```
+
+## Reload kdump
+
+```shell
+sudo kdumpctl reload
+```
+
+# Test
+
+```shell
+echo N | sudo tee /sys/module/kernel/parameters/crash_kexec_post_notifiers
+echo c | sudo tee /proc/sysrq-trigger
+```
diff --git a/hsavmcore/initramfs/fedora-rhel/dracut/modules.d/99hsavmcore/hsavmcore.service b/hsavmcore/initramfs/fedora-rhel/dracut/modules.d/99hsavmcore/hsavmcore.service
new file mode 100644
index 00000000..c2f83c2c
--- /dev/null
+++ b/hsavmcore/initramfs/fedora-rhel/dracut/modules.d/99hsavmcore/hsavmcore.service
@@ -0,0 +1,20 @@
+#  This file is part of systemd.
+#
+#  systemd is free software; you can redistribute it and/or modify it
+#  under the terms of the GNU Lesser General Public License as published by
+#  the Free Software Foundation; either version 2.1 of the License, or
+#  (at your option) any later version.
+
+[Unit]
+Description=hsavmcore Service
+After=initrd.target initrd-parse-etc.service sysroot.mount
+After=dracut-initqueue.service dracut-pre-mount.service dracut-mount.service dracut-pre-pivot.service
+Before=kdump-capture.service
+Before=initrd-cleanup.service
+
+[Service]
+Type=notify
+ExecStart=/usr/sbin/hsavmcore -c /etc/hsavmcore.conf
+StandardInput=null
+StandardOutput=syslog
+StandardError=syslog+console
diff --git a/hsavmcore/initramfs/fedora-rhel/dracut/modules.d/99hsavmcore/module-setup.sh b/hsavmcore/initramfs/fedora-rhel/dracut/modules.d/99hsavmcore/module-setup.sh
new file mode 100755
index 00000000..9cb36bd1
--- /dev/null
+++ b/hsavmcore/initramfs/fedora-rhel/dracut/modules.d/99hsavmcore/module-setup.sh
@@ -0,0 +1,37 @@
+#!/usr/bin/bash
+
+. $dracutfunctions
+
+if ! [[ -d "${initdir}/tmp" ]]; then
+    mkdir -p "${initdir}/tmp"
+fi
+
+check() {
+    [[ $debug ]] && set -x
+    #kdumpctl sets this explicitly
+    if [ -z "$IN_KDUMP" ]
+    then
+        return 1
+    fi
+    return 0
+}
+
+depends() {
+    local _dep="base shutdown"
+    echo $_dep
+    return 0
+}
+
+installkernel() {
+    hostonly='' instmods fuse
+}
+
+install() {
+    inst "/usr/sbin/hsavmcore" "/usr/sbin/hsavmcore"
+    inst "/etc/hsavmcore.conf" "/etc/hsavmcore.conf"
+    inst "$moddir/hsavmcore.service" "$systemdsystemunitdir/hsavmcore.service"
+    mkdir -p "$initdir/$systemdsystemunitdir/initrd.target.wants"
+    ln_r "$systemdsystemunitdir/hsavmcore.service" "$systemdsystemunitdir/initrd.target.wants/hsavmcore.service"
+
+    inst_hook pre-mount 30 "$moddir/setup-fuse.sh"
+}
diff --git a/hsavmcore/initramfs/fedora-rhel/dracut/modules.d/99hsavmcore/setup-fuse.sh b/hsavmcore/initramfs/fedora-rhel/dracut/modules.d/99hsavmcore/setup-fuse.sh
new file mode 100644
index 00000000..7d052ded
--- /dev/null
+++ b/hsavmcore/initramfs/fedora-rhel/dracut/modules.d/99hsavmcore/setup-fuse.sh
@@ -0,0 +1,3 @@
+#!/bin/sh
+
+modprobe fuse
diff --git a/hsavmcore/initramfs/sles/README.md b/hsavmcore/initramfs/sles/README.md
new file mode 100644
index 00000000..46088dc0
--- /dev/null
+++ b/hsavmcore/initramfs/sles/README.md
@@ -0,0 +1,141 @@
+
+# Setup
+
+## Configure crashkernel
+
+```shell
+sudo vim /etc/default/grub
+sudo sed -e 's/GRUB_CMDLINE_LINUX_DEFAULT="\(.*\)"/GRUB_CMDLINE_LINUX_DEFAULT="\1 crashkernel=512M"/' \
+         -i /etc/default/grub
+sudo grub2-mkconfig -o /boot/grub2/grub.cfg
+sudo reboot
+```
+
+## Production kernel's root file system
+
+- kdump mounts the production kernel's root file system under **/kdump/mnt1**.
+
+## Dependencies
+
+```shell
+sudo zypper install -y fuse fuse-devel systemd-devel
+```
+
+## Build hsavmcore
+
+```shell
+make -C s390-tools/hsavmcore
+```
+
+## Install hsavmcore
+
+```shell
+sudo cp s390-tools/hsavmcore/hsavmcore /usr/sbin/
+```
+
+## Create swap file
+
+```shell
+sudo dd if=/dev/zero of=/var/crash/swap.img bs=1M count=1024
+sudo mkswap /var/crash/swap.img
+```
+
+## Install hsavmcore.conf
+
+### Test configuration
+
+- Doesn't require HSA support
+
+#### HSA cache in file
+
+```shell
+cat <<EOF | sudo tee /etc/hsavmcore.conf
+verbose = 2
+workdir = /kdump/mnt1/var/crash
+use_hsa_mem = 0
+mount_debugfs = 1
+hsa_size = 0x1ffff000
+release_hsa = 0
+bind_mount_vmcore = 1
+EOF
+```
+
+#### HSA cache in memory
+
+```shell
+cat <<EOF | sudo tee /etc/hsavmcore.conf
+verbose = 2
+workdir = /kdump/mnt1/var/crash
+use_hsa_mem = 1
+mount_debugfs = 1
+hsa_size = 0x1ffff000
+release_hsa = 0
+bind_mount_vmcore = 1
+swap = /kdump/mnt1/var/crash/swap.img
+EOF
+```
+
+### Production configuration
+
+- Works only on s390x
+
+#### HSA cache in file
+
+```shell
+cat <<EOF | sudo tee /etc/hsavmcore.conf
+verbose = 2
+workdir = /kdump/mnt1/var/crash
+use_hsa_mem = 0
+mount_debugfs = 1
+hsa_size = -1
+release_hsa = 1
+bind_mount_vmcore = 1
+EOF
+```
+
+#### HSA cache in memory
+
+```shell
+cat <<EOF | sudo tee /etc/hsavmcore.conf
+verbose = 2
+workdir = /kdump/mnt1/var/crash
+use_hsa_mem = 1
+mount_debugfs = 1
+hsa_size = -1
+release_hsa = 1
+bind_mount_vmcore = 1
+swap = /kdump/mnt1/var/crash/swap.img
+EOF
+```
+
+## Install new dracut module
+
+```shell
+sudo cp -r s390-tools/hsavmcore/initramfs/sles/dracut/modules.d/99hsavmcore /usr/lib/dracut/modules.d/
+```
+
+## Add the new dracut module as a dependency to the dracut module *kdump*
+
+```shell
+sudo sed -e 's/_modules\[drm\]=/_modules[drm]=\n    _modules[hsavmcore]=/' \
+         -i /usr/lib/dracut/modules.d/99kdump/module-setup.sh
+```
+
+## Rebuild kdump initramfs
+
+```shell
+sudo mkdumprd -f
+```
+
+## Reload kdump
+
+```shell
+systemctl enable kdump
+systemctl restart kdump
+```
+
+# Test
+
+```shell
+echo c | sudo tee /proc/sysrq-trigger
+```
diff --git a/hsavmcore/initramfs/sles/dracut/modules.d/99hsavmcore/hsavmcore.service b/hsavmcore/initramfs/sles/dracut/modules.d/99hsavmcore/hsavmcore.service
new file mode 100644
index 00000000..66018fd3
--- /dev/null
+++ b/hsavmcore/initramfs/sles/dracut/modules.d/99hsavmcore/hsavmcore.service
@@ -0,0 +1,21 @@
+#  This file is part of systemd.
+#
+#  systemd is free software; you can redistribute it and/or modify it
+#  under the terms of the GNU Lesser General Public License as published by
+#  the Free Software Foundation; either version 2.1 of the License, or
+#  (at your option) any later version.
+
+# See systemd.special(7) for details
+
+[Unit]
+Description=hsavmcore Service
+Before=kdump-save.service
+ConditionPathExists=/etc/initrd-release
+ConditionPathExists=/proc/vmcore
+
+[Service]
+Type=notify
+ExecStart=/usr/sbin/hsavmcore -c /etc/hsavmcore.conf
+StandardInput=null
+StandardOutput=syslog
+StandardError=syslog+console
diff --git a/hsavmcore/initramfs/sles/dracut/modules.d/99hsavmcore/module-setup.sh b/hsavmcore/initramfs/sles/dracut/modules.d/99hsavmcore/module-setup.sh
new file mode 100755
index 00000000..0828bdab
--- /dev/null
+++ b/hsavmcore/initramfs/sles/dracut/modules.d/99hsavmcore/module-setup.sh
@@ -0,0 +1,47 @@
+#!/bin/bash
+
+. /lib/kdump/setup-kdump.functions
+
+kdump_needed() {
+    # Building a kdump initrd?
+    if [[ " $dracutmodules $add_dracutmodules $force_add_dracutmodules" == *\ $_mod\ * ]]; then
+        return 0
+    fi
+
+    # Is FADUMP active?
+    if [ "$KDUMP_FADUMP" = "yes" ]; then
+        return 0
+    fi
+
+    # Do not include kdump by default
+    return 1
+}
+
+check() {
+    # Get configuration
+    kdump_get_config || return 1
+
+    kdump_needed || return 1
+
+    return 0
+}
+
+depends() {
+    echo "systemd"
+    return 0
+}
+
+installkernel() {
+    hostonly='' instmods fuse
+}
+
+install() {
+    inst_simple /usr/sbin/hsavmcore
+    inst_simple /etc/hsavmcore.conf
+
+    inst "$moddir/hsavmcore.service" "$systemdsystemunitdir/hsavmcore.service"
+    mkdir -p "$initdir/$systemdsystemunitdir/initrd.target.wants"
+    ln_r "$systemdsystemunitdir/hsavmcore.service" "$systemdsystemunitdir/initrd.target.wants/hsavmcore.service"
+
+    inst_hook pre-mount 30 "$moddir/setup-fuse.sh"
+}
diff --git a/hsavmcore/initramfs/sles/dracut/modules.d/99hsavmcore/setup-fuse.sh b/hsavmcore/initramfs/sles/dracut/modules.d/99hsavmcore/setup-fuse.sh
new file mode 100644
index 00000000..7d052ded
--- /dev/null
+++ b/hsavmcore/initramfs/sles/dracut/modules.d/99hsavmcore/setup-fuse.sh
@@ -0,0 +1,3 @@
+#!/bin/sh
+
+modprobe fuse
diff --git a/hsavmcore/initramfs/ubuntu/README.md b/hsavmcore/initramfs/ubuntu/README.md
new file mode 100644
index 00000000..f51b3e83
--- /dev/null
+++ b/hsavmcore/initramfs/ubuntu/README.md
@@ -0,0 +1,142 @@
+# Setup
+
+## Production kernel's root file system
+
+- kdump mounts the production kernel's root file system under **/**.
+
+## debugfs
+
+- kdump mounts debugfs automatically.
+
+## Dependencies
+
+```shell
+sudo apt-get install -y make gcc kdump-tools fuse libfuse-dev libsystemd-dev
+```
+
+## Build hsavmcore
+
+```shell
+make -C s390-tools/hsavmcore
+```
+
+## Install hsavmcore
+
+```shell
+sudo cp s390-tools/hsavmcore/hsavmcore /usr/sbin/
+```
+
+## Create swap file
+
+```shell
+sudo dd if=/dev/zero of=/var/crash/swap.img bs=1M count=1024
+sudo mkswap /var/crash/swap.img
+```
+
+## Install hsavmcore.conf
+
+### Test configuration
+
+- Doesn't require HSA support
+
+#### HSA cache in file
+
+```shell
+cat <<EOF | sudo tee /etc/hsavmcore.conf
+verbose = 2
+workdir = /sysroot/var/crash
+use_hsa_mem = 0
+mount_debugfs = 0
+hsa_size = 0x1ffff000
+release_hsa = 0
+bind_mount_vmcore = 1
+EOF
+```
+
+#### HSA cache in memory
+
+```shell
+cat <<EOF | sudo tee /etc/hsavmcore.conf
+verbose = 2
+workdir = /var/crash
+use_hsa_mem = 1
+mount_debugfs = 0
+hsa_size = 0x1ffff000
+release_hsa = 0
+bind_mount_vmcore = 1
+swap = /var/crash/swap.img
+EOF
+```
+
+### Production configuration
+
+- Works only on s390x
+
+#### HSA cache in file
+
+```shell
+cat <<EOF | sudo tee /etc/hsavmcore.conf
+verbose = 2
+workdir = /var/crash
+use_hsa_mem = 0
+mount_debugfs = 0
+hsa_size = -1
+release_hsa = 1
+bind_mount_vmcore = 1
+EOF
+```
+
+#### HSA cache in memory
+
+```shell
+cat <<EOF | sudo tee /etc/hsavmcore.conf
+verbose = 2
+workdir = /sysroot/var/crash
+use_hsa_mem = 1
+mount_debugfs = 0
+hsa_size = -1
+release_hsa = 1
+bind_mount_vmcore = 1
+swap = /var/crash/swap.img
+EOF
+```
+
+## Install new dracut module
+
+```shell
+sudo cp s390-tools/hsavmcore/initramfs/ubuntu/hsavmcore.service /usr/lib/systemd/system/
+```
+
+## Add the new systemd service as a dependency to the service *kdump-tools-dump*
+
+```shell
+Wants=network-online.target dbus.socket systemd-resolved.service hsavmcore.service
+After=network-online.target dbus.socket systemd-resolved.service hsavmcore.service
+
+sudo sed -e 's/Wants=\(.*\)$/Wants=\1 hsavmcore.service/' \
+         -e 's/After=\(.*\)$/After=\1 hsavmcore.service/' \
+         -i /usr/lib/systemd/system/kdump-tools-dump.service
+```
+
+## Rebuild kdump initramfs
+
+```shell
+sudo rm -rf /var/lib/kdump/initrd*
+sudo kdump-config unload
+sudo kdump-config load
+sudo systemctl restart kdump-tools
+```
+
+## Reload kdump
+
+```shell
+sudo kdump-config unload
+sudo kdump-config load
+```
+
+# Test
+
+```shell
+echo N | sudo tee /sys/module/kernel/parameters/crash_kexec_post_notifiers
+echo c | sudo tee /proc/sysrq-trigger
+```
diff --git a/hsavmcore/initramfs/ubuntu/hsavmcore.service b/hsavmcore/initramfs/ubuntu/hsavmcore.service
new file mode 100644
index 00000000..6e3dbe2b
--- /dev/null
+++ b/hsavmcore/initramfs/ubuntu/hsavmcore.service
@@ -0,0 +1,22 @@
+#  This file is part of systemd.
+#
+#  systemd is free software; you can redistribute it and/or modify it
+#  under the terms of the GNU Lesser General Public License as published by
+#  the Free Software Foundation; either version 2.1 of the License, or
+#  (at your option) any later version.
+
+[Unit]
+Description=hsavmcore Service
+Wants=network-online.target dbus.socket systemd-resolved.service
+After=network-online.target dbus.socket systemd-resolved.service
+Before=kdump-tools-dump.service
+
+[Install]
+WantedBy=kdump-tools-dump.service
+
+[Service]
+Type=notify
+ExecStart=/usr/sbin/hsavmcore -c /etc/hsavmcore.conf
+StandardInput=null
+StandardOutput=syslog+console
+StandardError=syslog+console