Add kdump dracut config

In some cases, we need to change dracut [omit_]dracutmodules to
customize the first kernel's initrd to meet the needs, such as
bootc and CoreOS[1].

In most cases kdump does not use these modules, but the change of
[omit]_dracutmodules may break existing functionality. For example,
if we set omit_dracutmodules='nfs', the nfs module cannot be added
even if we use "dracut_args --force-add 'nfs'".

Some dracut conf[2] may use "dracutmodules+='some modules'" instead of
"add_dracutmodules+='some modules'". When dracutmodules is not empty,
dracut will only include the specified dracut modules, this causes
the initrd doesn't include the necessary modules and kdump will not
work.

It is better to maintain its own dracut config for kdump. This patch
moved the hardcoded dracut args to the new conf dir
/lib/kdump/dracut.conf.d/99-kdump.conf.

Dracut will support --add-confdir start by 104, kdump can use this
option when building kdump initramfs.

See also:
[1] #11
[2] https://issues.redhat.com/browse/RHEL-49590?focusedId=25197134&page=com.atlassian.jira.plugin.system.issuetabpanels%3Acomment-tabpanel#comment-25197134

Suggested-by: Dave Young <[email protected]>
Suggested-by: Colin Walters <[email protected]>
Signed-off-by: Lichen Liu <[email protected]>

99-kdump.conf

@@ -0,0 +1,3 @@
+dracutmodules=''
+add_dracutmodules+='kdumpbase'
+omit_dracutmodules+='rdma plymouth resume ifcfg earlykdump'

Makefile

@@ -33,7 +33,7 @@ manpages:
 	install -D -m 644 kdump.conf.5 $(DESTDIR)$(mandir)/man5/kdump.conf.5
 
 install: dracut-modules kdump-conf kdump-sysconfig manpages
-	mkdir -p $(DESTDIR)$(pkglibdir)
+	mkdir -p $(DESTDIR)$(pkglibdir)/dracut.conf.d
 	mkdir -p -m755 $(DESTDIR)$(sysconfdir)/kdump/pre.d
 	mkdir -p -m755 $(DESTDIR)$(sysconfdir)/kdump/post.d
 	mkdir -p -m755 $(DESTDIR)$(localstatedir)/crash
@@ -46,6 +46,7 @@ install: dracut-modules kdump-conf kdump-sysconfig manpages
 	install -D -m 644 kdump.conf $(DESTDIR)$(sysconfdir)
 	install -D -m 644 kdump.sysconfig $(DESTDIR)$(sysconfdir)/sysconfig/kdump
 	install -D -m 755 kdump-lib.sh kdump-lib-initramfs.sh kdump-logger.sh -t $(DESTDIR)$(pkglibdir)
+	install -D -m 644 99-kdump.conf -t $(DESTDIR)$(pkglibdir)/dracut.conf.d
 
 ifeq ($(ARCH), $(filter ppc64le ppc64,$(ARCH)))
 	install -m 755 mkfadumprd $(DESTDIR)$(sbindir)

mkdumprd

@@ -29,15 +29,13 @@ SSH_KEY_LOCATION=$DEFAULT_SSHKEY
 SAVE_PATH=$(get_save_path)
 
 declare -a dracut_args
-dracut_args+=(--add kdumpbase)
 dracut_args+=(--quiet)
 dracut_args+=(--hostonly)
 dracut_args+=(--hostonly-cmdline)
 dracut_args+=(--hostonly-i18n)
 dracut_args+=(--hostonly-mode strict)
 dracut_args+=(--hostonly-nics '')
 dracut_args+=(--aggressive-strip)
-dracut_args+=(--omit "rdma plymouth resume ifcfg earlykdump")
 
 MKDUMPRD_TMPDIR="$(mktemp -d -t mkdumprd.XXXXXX)"
 [ -d "$MKDUMPRD_TMPDIR" ] || perror_exit "dracut: mktemp -p -d -t dracut.XXXXXX failed."
@@ -441,4 +439,13 @@ elif ! is_fadump_capable && \
 	add_mount "$status_target"
 fi
 
+# Use kdump managed dracut profile.
+[[ $kdump_dracut_confdir ]] || kdump_dracut_confdir=/lib/kdump/dracut.conf.d
+if [[ "$(dracut --help)" == *--add-confdir* ]] && [[ -d "$kdump_dracut_confdir" ]]; then
+	dracut_args+=("--add-confdir" "$kdump_dracut_confdir")
+else
+	dracut_args+=(--add kdumpbase)
+	dracut_args+=(--omit "rdma plymouth resume ifcfg earlykdump")
+fi
+
 dracut "${dracut_args[@]}" "$@"