[PATCH v2 1/2] kdump/fadump: fix network interface name when switching from fadump to kdump
When a remote dump target is specified, kdump dracut module prefixes 'kdump-' to network interface name (ifname) as kernel assigned names are not persistent. In fadump mode, kdump dracut module is added to the default initrd, which adds the 'kdump-' prefix to the ifname of the prodcution kernel itself. If fadump mode is disabled after this, kdump dracut module picks the ifname that is already prefixed with 'kdump-' in the production kernel and adds another 'kdump-' to it, making the ifname something like kdump-kdump-eth0 for kdump kernel. Eventually, kdump kernel fails with below traces:
dracut-initqueue[246]: RTNETLINK answers: Network is unreachable dracut-initqueue[246]: arping: Device kdump-kdump-eth0 not available.
The ip command shows the below:
kdump:/# ip addr show kdump-kdump-eth0 2: kdump-kdump-eth: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 \ qdisc pfifo_fast state UNKNOWN qlen 1000 link/ether 22:82:87:7b:98:02 brd ff:ff:ff:ff:ff:ff inet6 2002:903:15f:550:2082:87ff:fe7b:9802/64 scope global \ mngtmpaddr dynamic valid_lft 2591890sec preferred_lft 604690sec inet6 fe80::2082:87ff:fe7b:9802/64 scope link valid_lft forever preferred_lft forever kdump:/#
The trailing 0 from kdump-kdump-eth0 is missing in the ifname, probably truncated while setting.
This patch fixes this by avoiding addition of the prefix 'kdump-' when such prefix is already present in the ifname.
Signed-off-by: Hari Bathini hbathini@linux.vnet.ibm.com ---
* No changes from v1.
dracut-module-setup.sh | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-)
diff --git a/dracut-module-setup.sh b/dracut-module-setup.sh index 68e0ff8..490501a 100755 --- a/dracut-module-setup.sh +++ b/dracut-module-setup.sh @@ -161,7 +161,8 @@ kdump_get_perm_addr() { kdump_setup_ifname() { local _ifname
- if [[ $1 =~ eth* ]]; then + # If ifname has 'kdump-' prefix, don't add it again + if [[ $1 =~ eth* ]] && [[ ! $1 =~ ^kdump-* ]]; then _ifname="kdump-$1" else _ifname="$1"
When fadump mode is enabled, the default initrd is rebuilt with kdump dracut module. As the default initrd is altered, the original default initrd is backed up. But we are not restoring it when fadump mode is disabled. This patch tries to restore the backed up default initrd on disabling fadump mode.
Signed-off-by: Hari Bathini hbathini@linux.vnet.ibm.com ---
Changes from v1: * Using `uname -r` for kernel version instead of $kdump-kver for backup/restore.
kdumpctl | 42 ++++++++++++++++++++++++++++++++---------- 1 file changed, 32 insertions(+), 10 deletions(-)
diff --git a/kdumpctl b/kdumpctl index 8d0ab81..ea95032 100755 --- a/kdumpctl +++ b/kdumpctl @@ -154,9 +154,6 @@ rebuild_fadump_initrd() { local target_initrd_tmp
- # backup fadump initrd for reference before replacing it - backup_initrd - # this file tells the initrd is fadump enabled touch /tmp/fadump.initramfs target_initrd_tmp="$TARGET_INITRD.tmp" @@ -190,8 +187,17 @@ rebuild_kdump_initrd() rebuild_initrd() { if [ $DEFAULT_DUMP_MODE == "fadump" ]; then + # backup initrd for reference before replacing it + # with fadump aware initrd + backup_restore_default_initrd "backup" + rebuild_fadump_initrd else + # check if a backup of default initrd exists. If yes, + # it signifies a switch from fadump mode. So, restore + # the backed up default initrd. + backup_restore_default_initrd "restore" + rebuild_kdump_initrd fi
@@ -220,15 +226,31 @@ check_executable() done }
-backup_initrd() +backup_restore_default_initrd() { - local target_initrd_bak + local default_initrd + local default_initrd_bak + local action=$1 + + default_initrd="${KDUMP_BOOTDIR}/initramfs-`uname -r`.img" + default_initrd_bak="${KDUMP_BOOTDIR}/.initramfs-`uname -r`.img.default"
- # Check if backup initrd is already present. - target_initrd_bak="$TARGET_INITRD.bak" - if [ ! -e $target_initrd_bak ];then - echo "Backing up $TARGET_INITRD" - cp $TARGET_INITRD $target_initrd_bak + if [[ $action != "restore" ]]; then + if [ ! -e $default_initrd_bak ]; then + echo "Backing up $default_initrd" + cp $default_initrd $default_initrd_bak + fi + else + # If a backup initrd exists, we must be switching back from + # fadump to kdump. Restore the original default initrd. + if [ -f $default_initrd_bak ];then + mv $default_initrd_bak $default_initrd + if [[ $? -eq 0 ]]; then + echo -n "Default initrd is restored as fadump mode " + echo "is disabled" + sync + fi + fi fi }
-
Hari Bathini