mkdumprd: Add dracut watchdog module as default option

If dracut watchdog module is enabled then, it includes kernel watchdog
module of active watchdog device in initramfs.

kdump.conf has an option to modify dracut_args. So, if an user passes "-a
watchdog" in dracut_args then dracut will add kernel watchdog module of
active watchdog device in initramfs.

Since, kexec-tools always requires to add kernel watchdog module of active
watchdog device in initramfs, therefore even when an user does not pass any
watchdog option and there exists at least one active watchdog device then
also kexec-tools adds "-a watchdog" in dracut args.

Therefore, if an user does not want to add kernel watchdog module in
initramfs then the person must pass "-o watchdog" in dracut_args.

Signed-off-by: Pratyush Anand <panand@redhat.com>
Acked-by: Dave Young <dyoung@redhat.com>

kdump-lib.sh

@@ -382,3 +382,27 @@ get_ifcfg_filename() {
 
     echo -n "${ifcfg_file}"
 }
+
+# returns 0 when omission of watchdog module is desired in dracut_args
+# returns 1 otherwise
+is_wdt_mod_omitted() {
+	local dracut_args
+	local ret=1
+
+	dracut_args=$(grep  "^dracut_args" /etc/kdump.conf)
+	[[ -z $dracut_args ]] && return $ret
+
+	eval set -- $dracut_args
+	while :; do
+		[[ -z $1 ]] && break
+		case $1 in
+			-o|--omit)
+				echo $2 | grep -qw "watchdog"
+				[[ $? == 0 ]] && ret=0
+				break
+		esac
+		shift
+	done
+
+	return $ret
+}

mkdumprd

@@ -16,8 +16,26 @@ SAVE_PATH=$(grep ^path $conf_file| cut -d' '  -f2)
 # strip the duplicated "/"
 SAVE_PATH=$(echo $SAVE_PATH | tr -s /)
 
+is_wdt_addition_needed() {
+	local active
+
+	is_wdt_mod_omitted
+	[[ $? -eq 0 ]] && return 1
+	[[ -d /sys/class/watchdog/ ]] || return 1
+	for dir in /sys/class/watchdog/*; do
+		[[ -f "$dir/state" ]] || continue
+		active=$(< "$dir/state")
+		[[ "$active" =  "active" ]] && return 0
+	done
+	return 1
+}
+
+WDTCFG=""
+is_wdt_addition_needed
+[[ $? -eq 0 ]] && WDTCFG="-a watchdog"
+
 extra_modules=""
-dracut_args=("--hostonly" "-o" "plymouth dash resume ifcfg")
+dracut_args=("--hostonly" "-o" "plymouth dash resume ifcfg" $WDTCFG)
 OVERRIDE_RESETTABLE=0
 
 add_dracut_arg() {