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.

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'".

It is better to maintain its own dracut config for kdump. As the
first try, we start by keeping [omit_]dracutmodules empty.

As a side effect, the default confdir "/etc/dracut.conf.d" will
not work while generating kdump initrd.

And dracut can only use --confdir once, so "dracut_args --confidr"
in /etc/kdump.conf will no longer work. This may be avoided in the
future by adding something like "--extra-confdir" to dracut.

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

99-kdump.conf

@@ -0,0 +1,2 @@
+dracutmodules=''
+omit_dracutmodules=''

Makefile

@@ -46,7 +46,7 @@ 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
@@ -59,6 +59,7 @@ 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

@@ -414,4 +414,7 @@ if ! is_fadump_capable; then
 	fi
 fi
 
+[[ $kdumpdracutconfdir ]] || kdumpdracutconfdir=/lib/kdump/dracut.conf.d
+[ -d "$kdumpdracutconfdir" ] && add_dracut_arg "--confdir" "$kdumpdracutconfdir"
+
 dracut "${dracut_args[@]}" "$@"