In case of fadump, the initramfs image has to be built to boot into
the production environment as well as to offload the active crash dump
to the specified dump target (for boot after crash). As the same image
would be used for both boot scenarios, it could not be built optimally
while accommodating both cases.
Use --include to include the initramfs image built for offloading
active crash dump to the specified dump target. Also, introduce a new
out-of-tree dracut module (99zz-fadumpinit) that installs a customized
init program while moving the default /init to /init.dracut. This
customized init program is leveraged to isolate fadump image within
the default initramfs image by kicking off default boot process
(exec /init.dracut) for regular boot scenario and activating fadump
initramfs image, if the system is booting after a crash.
If squash is available, ensure default initramfs image is also built
with squash module to reduce memory consumption in capture kernel.
Signed-off-by: Hari Bathini <hbathini(a)linux.ibm.com>
Signed-off-by: Kairui Song <kasong(a)redhat.com>
---
* This patch depends on the below 3 dracut PRs:
-
https://github.com/dracutdevs/dracut/pull/1532
-
https://github.com/dracutdevs/dracut/pull/1535
-
https://github.com/dracutdevs/dracut/pull/1545
Changes in V4:
* Moved is_squash_available() into kdump-lib.sh to reuse in mkfadumprd.
* Added a condition in mkfadumprd to build default initramfs with squash
module, if squash is available.
* pivot_root util used to change '/' when squash is used while building
default initramfs (Kairui).
* Changed mv, switch_root utils installations to be conditional on squash
module availability.
* Changed moving files from /fadumproot to use "$(ls -A /fadumproot)" to
ensure file names beginning with "." are also moved.
* Added a TODO at is_fadump_capable() check in mkdumprd for removing it
eventually.
Changes in V3:
* Removed dependency with squash module by extracting fadump
initramfs to /fadumproot directory.
* Moved code that builds initramfs for fadump to mkfadumprd and
added cleanup support based on inputs from Kairui.
Changes in V2:
* Moved kernel modules installation from install() to installkernel()
for zz-fadumpinit dracut module.
* Updated kexec-tools.spec to install zz-fadumpinit module files
appropriately.
* Fixed error check for capture initramfs image isolation with dracut.
dracut-fadump-init-fadump.sh | 44 ++++++++++++++++++++++++++++++
dracut-fadump-module-setup.sh | 23 ++++++++++++++++
dracut-module-setup.sh | 16 +----------
kdump-lib.sh | 10 +++++++
kdumpctl | 22 +++------------
kexec-tools.spec | 14 ++++++++++
mkdumprd | 5 +++
mkfadumprd | 60 +++++++++++++++++++++++++++++++++++++++++
8 files changed, 162 insertions(+), 32 deletions(-)
create mode 100755 dracut-fadump-init-fadump.sh
create mode 100644 dracut-fadump-module-setup.sh
create mode 100644 mkfadumprd
diff --git a/dracut-fadump-init-fadump.sh b/dracut-fadump-init-fadump.sh
new file mode 100755
index 0000000..5468d99
--- /dev/null
+++ b/dracut-fadump-init-fadump.sh
@@ -0,0 +1,44 @@
+#!/bin/sh
+export PATH=/usr/bin:/usr/sbin
+export SYSTEMD_IN_INITRD=lenient
+
+[ -e /proc/mounts ] ||
+ (mkdir -p /proc && mount -t proc -o nosuid,noexec,nodev proc /proc)
+
+grep -q '^sysfs /sys sysfs' /proc/mounts ||
+ (mkdir -p /sys && mount -t sysfs -o nosuid,noexec,nodev sysfs /sys)
+
+grep -q '^none / ' /proc/mounts || grep -q '^rootfs / ' /proc/mounts
&& ROOTFS_IS_RAMFS=1
+
+if [ -f /proc/device-tree/rtas/ibm,kernel-dump ] || [ -f
/proc/device-tree/ibm,opal/dump/mpipl-boot ]; then
+ mkdir /newroot
+ mount -t ramfs ramfs /newroot
+
+ if [ $ROOTFS_IS_RAMFS ]; then
+ for FILE in $(ls -A /fadumproot/); do
+ mv /fadumproot/$FILE /newroot/
+ done
+ exec switch_root /newroot /init
+ else
+ mkdir /newroot/sys /newroot/proc /newroot/oldroot
+ mount --move /proc /newroot/proc
+ mount --move /sys /newroot/sys
+ cp --reflink=auto --sparse=auto --preserve=mode,timestamps,links -dfr /fadumproot/.
/newroot/
+ cd /newroot && pivot_root . oldroot
+
+ loop=1
+ while [ $loop ]; do
+ unset loop
+ while read -r _ mp _; do
+ case $mp in
+ /oldroot/*) umount "$mp" && loop=1 ;;
+ esac
+ done </proc/mounts
+ done
+ umount -l oldroot
+
+ exec /init
+ fi
+else
+ exec /init.dracut
+fi
diff --git a/dracut-fadump-module-setup.sh b/dracut-fadump-module-setup.sh
new file mode 100644
index 0000000..f062486
--- /dev/null
+++ b/dracut-fadump-module-setup.sh
@@ -0,0 +1,23 @@
+#!/bin/bash
+
+check() {
+ return 255
+}
+
+depends() {
+ return 0
+}
+
+install() {
+ mv -f "$initdir/init" "$initdir/init.dracut"
+ inst_script "$moddir/init-fadump.sh" /init
+ chmod a+x "$initdir/init"
+
+ # Install required binaries for the init script (init-fadump.sh)
+ inst_multiple sh modprobe grep mkdir mount
+ if dracut_module_included "squash"; then
+ inst_multiple cp pivot_root umount
+ else
+ inst_multiple ls mv switch_root
+ fi
+}
diff --git a/dracut-module-setup.sh b/dracut-module-setup.sh
index 35a961a..c8d7f08 100755
--- a/dracut-module-setup.sh
+++ b/dracut-module-setup.sh
@@ -27,17 +27,7 @@ depends() {
[[ " $omit_dracutmodules " != *\ $1\ * ]] && _dep="$_dep
$1"
}
- is_squash_available() {
- for kmodule in squashfs overlay loop; do
- if [ -z "$KDUMP_KERNELVER" ]; then
- modprobe --dry-run $kmodule &>/dev/null || return 1
- else
- modprobe -S $KDUMP_KERNELVER --dry-run $kmodule &>/dev/null ||
return 1
- fi
- done
- }
-
- if is_squash_available && ! is_fadump_capable; then
+ if is_squash_available; then
add_opt_module squash
else
dwarning "Required modules to build a squashed kdump image is
missing!"
@@ -1085,7 +1075,5 @@ install() {
${initdir}/etc/lvm/lvm.conf &>/dev/null
# Save more memory by dropping switch root capability
- if ! is_fadump_capable; then
- dracut_no_switch_root
- fi
+ dracut_no_switch_root
}
diff --git a/kdump-lib.sh b/kdump-lib.sh
index 27741fb..8e618f8 100755
--- a/kdump-lib.sh
+++ b/kdump-lib.sh
@@ -19,6 +19,16 @@ is_fadump_capable()
return 1
}
+is_squash_available() {
+ for kmodule in squashfs overlay loop; do
+ if [ -z "$KDUMP_KERNELVER" ]; then
+ modprobe --dry-run $kmodule &>/dev/null || return 1
+ else
+ modprobe -S $KDUMP_KERNELVER --dry-run $kmodule &>/dev/null || return
1
+ fi
+ done
+}
+
perror_exit() {
derror "$@"
exit 1
diff --git a/kdumpctl b/kdumpctl
index 978dae5..26247d1 100755
--- a/kdumpctl
+++ b/kdumpctl
@@ -8,6 +8,7 @@ KEXEC_ARGS=""
KDUMP_CONFIG_FILE="/etc/kdump.conf"
KDUMP_LOG_PATH="/var/log"
MKDUMPRD="/sbin/mkdumprd -f"
+MKFADUMPRD="/sbin/mkfadumprd"
DRACUT_MODULES_FILE="/usr/lib/dracut/modules.txt"
SAVE_PATH=/var/crash
SSH_KEY_LOCATION="/root/.ssh/kdump_id_rsa"
@@ -104,25 +105,10 @@ save_core()
rebuild_fadump_initrd()
{
- local target_initrd_tmp
-
- # this file tells the initrd is fadump enabled
- touch /tmp/fadump.initramfs
- target_initrd_tmp="$TARGET_INITRD.tmp"
- ddebug "rebuild fadump initrd: $target_initrd_tmp $DEFAULT_INITRD_BAK
$KDUMP_KERNELVER"
- $MKDUMPRD $target_initrd_tmp --rebuild $DEFAULT_INITRD_BAK --kver $KDUMP_KERNELVER \
- -i /tmp/fadump.initramfs /etc/fadump.initramfs
- if [ $? != 0 ]; then
- derror "mkdumprd: failed to rebuild initrd with fadump support"
- rm -f /tmp/fadump.initramfs
+ if ! $MKFADUMPRD "$DEFAULT_INITRD_BAK" "$TARGET_INITRD" --kver
"$KDUMP_KERNELVER"; then
+ derror "mkfadumprd: failed to make fadump initrd"
return 1
fi
- rm -f /tmp/fadump.initramfs
-
- # updating fadump initrd
- ddebug "updating fadump initrd: $target_initrd_tmp $TARGET_INITRD"
- mv $target_initrd_tmp $TARGET_INITRD
- sync
return 0
}
@@ -612,7 +598,7 @@ check_rebuild()
#in case of fadump mode, check whether the default/target
#initrd is already built with dump capture capability
if [ "$DEFAULT_DUMP_MODE" == "fadump" ]; then
- capture_capable_initrd=$(lsinitrd -f $DRACUT_MODULES_FILE $TARGET_INITRD | grep
^kdumpbase$ | wc -l)
+ capture_capable_initrd=$(lsinitrd -f $DRACUT_MODULES_FILE $TARGET_INITRD | grep -e
^kdumpbase$ -e ^zz-fadumpinit$ | wc -l)
fi
fi
diff --git a/kexec-tools.spec b/kexec-tools.spec
index 7b29b0e..f43c186 100644
--- a/kexec-tools.spec
+++ b/kexec-tools.spec
@@ -39,6 +39,7 @@ Source28: kdump-udev-throttler
Source29: kdump.sysconfig.aarch64
Source30: 60-kdump.install
Source31: kdump-logger.sh
+Source32: mkfadumprd
#######################################
# These are sources for mkdumpramfs
@@ -54,6 +55,9 @@ Source107: dracut-kdump-emergency.target
Source108: dracut-early-kdump.sh
Source109: dracut-early-kdump-module-setup.sh
+Source200: dracut-fadump-init-fadump.sh
+Source201: dracut-fadump-module-setup.sh
+
Requires(post): systemd-units
Requires(preun): systemd-units
Requires(postun): systemd-units
@@ -176,6 +180,7 @@ SYSCONFIG=$RPM_SOURCE_DIR/kdump.sysconfig.%{_target_cpu}
install -m 644 $SYSCONFIG $RPM_BUILD_ROOT%{_sysconfdir}/sysconfig/kdump
install -m 755 %{SOURCE7} $RPM_BUILD_ROOT/usr/sbin/mkdumprd
+install -m 755 %{SOURCE32} $RPM_BUILD_ROOT/usr/sbin/mkfadumprd
install -m 644 %{SOURCE8} $RPM_BUILD_ROOT%{_sysconfdir}/kdump.conf
install -m 644 kexec/kexec.8 $RPM_BUILD_ROOT%{_mandir}/man8/kexec.8
install -m 644 %{SOURCE12} $RPM_BUILD_ROOT%{_mandir}/man8/mkdumprd.8
@@ -211,6 +216,7 @@ install -m 644 makedumpfile-%{mkdf_ver}/eppic_scripts/*
$RPM_BUILD_ROOT/usr/shar
%define remove_dracut_prefix() %(echo -n %1|sed 's/.*dracut-//g')
%define remove_dracut_early_kdump_prefix() %(echo -n %1|sed
's/.*dracut-early-kdump-//g')
+%define remove_dracut_fadump_prefix() %(echo -n %1|sed 's/.*dracut-fadump-//g')
# deal with dracut modules
mkdir -p -m755 $RPM_BUILD_ROOT/etc/kdump-adv-conf/kdump_dracut_modules/99kdumpbase
@@ -228,6 +234,13 @@ cp %{SOURCE108}
$RPM_BUILD_ROOT/etc/kdump-adv-conf/kdump_dracut_modules/99earlyk
cp %{SOURCE109}
$RPM_BUILD_ROOT/etc/kdump-adv-conf/kdump_dracut_modules/99earlykdump/%{remove_dracut_early_kdump_prefix
%{SOURCE109}}
chmod 755
$RPM_BUILD_ROOT/etc/kdump-adv-conf/kdump_dracut_modules/99earlykdump/%{remove_dracut_prefix
%{SOURCE108}}
chmod 755
$RPM_BUILD_ROOT/etc/kdump-adv-conf/kdump_dracut_modules/99earlykdump/%{remove_dracut_early_kdump_prefix
%{SOURCE109}}
+%ifarch ppc64 ppc64le
+mkdir -p -m755 $RPM_BUILD_ROOT/etc/kdump-adv-conf/kdump_dracut_modules/99zz-fadumpinit
+cp %{SOURCE200}
$RPM_BUILD_ROOT/etc/kdump-adv-conf/kdump_dracut_modules/99zz-fadumpinit/%{remove_dracut_fadump_prefix
%{SOURCE200}}
+cp %{SOURCE201}
$RPM_BUILD_ROOT/etc/kdump-adv-conf/kdump_dracut_modules/99zz-fadumpinit/%{remove_dracut_fadump_prefix
%{SOURCE201}}
+chmod 755
$RPM_BUILD_ROOT/etc/kdump-adv-conf/kdump_dracut_modules/99zz-fadumpinit/%{remove_dracut_fadump_prefix
%{SOURCE200}}
+chmod 755
$RPM_BUILD_ROOT/etc/kdump-adv-conf/kdump_dracut_modules/99zz-fadumpinit/%{remove_dracut_fadump_prefix
%{SOURCE201}}
+%endif
%define dracutlibdir %{_prefix}/lib/dracut
@@ -309,6 +322,7 @@ done
/usr/sbin/makedumpfile
%endif
/usr/sbin/mkdumprd
+/usr/sbin/mkfadumprd
/usr/sbin/vmcore-dmesg
%{_bindir}/*
%{_datadir}/kdump
diff --git a/mkdumprd b/mkdumprd
index 6d699c3..89a160d 100644
--- a/mkdumprd
+++ b/mkdumprd
@@ -452,6 +452,11 @@ then
add_dracut_arg "--add-drivers" \"$extra_modules\"
fi
+# TODO: The below check is not needed anymore with the introduction of
+# 'zz-fadumpinit' module, that isolates fadump's capture kernel
initrd,
+# but still sysroot.mount unit gets generated based on 'root=' kernel
+# parameter available in fadump case. So, find a way to fix that first
+# before removing this check.
if ! is_fadump_capable; then
# The 2nd rootfs mount stays behind the normal dump target mount,
# so it doesn't affect the logic of check_dump_fs_modified().
diff --git a/mkfadumprd b/mkfadumprd
new file mode 100644
index 0000000..4af4ae6
--- /dev/null
+++ b/mkfadumprd
@@ -0,0 +1,60 @@
+#!/bin/bash --norc
+# Generate an initramfs image that isolates dump capture capability within
+# the default initramfs using zz-fadumpinit dracut module.
+
+if [ -f /etc/sysconfig/kdump ]; then
+ . /etc/sysconfig/kdump
+fi
+
+[[ $dracutbasedir ]] || dracutbasedir=/usr/lib/dracut
+. $dracutbasedir/dracut-functions.sh
+. /lib/kdump/kdump-lib.sh
+. /lib/kdump/kdump-logger.sh
+
+#initiate the kdump logger
+if ! dlog_init; then
+ echo "mkfadumprd: failed to initiate the kdump logger."
+ exit 1
+fi
+
+readonly MKFADUMPRD_TMPDIR="$(mktemp -d -t mkfadumprd.XXXXXX)"
+[ -d "$MKFADUMPRD_TMPDIR" ] || perror_exit "mkfadumprd: mktemp -d -t
mkfadumprd.XXXXXX failed."
+trap '
+ ret=$?;
+ [[ -d $MKFADUMPRD_TMPDIR ]] && rm --one-file-system -rf --
"$MKFADUMPRD_TMPDIR";
+ exit $ret;
+ ' EXIT
+
+# clean up after ourselves no matter how we die.
+trap 'exit 1;' SIGINT
+
+MKDUMPRD="/sbin/mkdumprd -f"
+# Default boot initramfs to be rebuilt
+REBUILD_INITRD="$1" && shift
+TARGET_INITRD="$1" && shift
+FADUMP_INITRD="$MKFADUMPRD_TMPDIR/fadump.img"
+
+### First build an initramfs with dump capture capability
+# this file tells the initrd is fadump enabled
+touch "$MKFADUMPRD_TMPDIR/fadump.initramfs"
+ddebug "rebuild fadump initrd: $FADUMP_INITRD $DEFAULT_INITRD
$KDUMP_KERNELVER"
+if ! $MKDUMPRD "$FADUMP_INITRD" -i
"$MKFADUMPRD_TMPDIR/fadump.initramfs" /etc/fadump.initramfs; then
+ perror_exit "mkfadumprd: failed to build image with dump capture support"
+fi
+
+### Unpack the initramfs having dump capture capability
+mkdir -p "$MKFADUMPRD_TMPDIR/fadumproot"
+if ! (pushd "$MKFADUMPRD_TMPDIR/fadumproot" > /dev/null && lsinitrd
--unpack "$MKFADUMPRD_TMPDIR/fadump.img" && \
+ popd > /dev/null); then
+ derror "mkfadumprd: failed to unpack '$MKFADUMPRD_TMPDIR'"
+ exit 1
+fi
+
+### Pack it into the normal boot initramfs with zz-fadumpinit module
+_dracut_isolate_args="--rebuild $REBUILD_INITRD --add zz-fadumpinit -i
$MKFADUMPRD_TMPDIR/fadumproot /fadumproot"
+if is_squash_available; then
+ _dracut_isolate_args="$_dracut_isolate_args --add squash"
+fi
+if ! dracut --force --quiet $_dracut_isolate_args $@ "$TARGET_INITRD"; then
+ perror_exit "mkfadumprd: failed to setup '$TARGET_INITRD' with dump capture
capability"
+fi