[PATCH v2 6/9] Change dump_to_rootfs to use "--mount" instead of "root=X"

[Xunlei Pang]

Currently, we kept "root=X" for the dump_to_rootfs case, this
patch consolidates to use "--mount" for all the kdump mounts.

One advantage of this way is that dracut can correctly mark root
(in case of dump_to_rootfs is specified) as the host device when
"--no-hostonly-default-device" is added in the following patch.

Changed the code style in passing, as shellcheck tool reported:
Use $(..) instead of deprecated `..`

Signed-off-by: Xunlei Pang <xlpang(a)redhat.com&gt;
---
 kdumpctl | 17 +++++++----------
 mkdumprd |  6 ++++++
 2 files changed, 13 insertions(+), 10 deletions(-)

diff --git a/kdumpctl b/kdumpctl
index 4c11bc9..114a09d 100755
--- a/kdumpctl
+++ b/kdumpctl
@@ -181,32 +181,29 @@ prepare_cmdline()
 	local cmdline id
 
 	if [ -z "$KDUMP_COMMANDLINE" ]; then
-		cmdline=`cat /proc/cmdline`
+		cmdline=$(cat /proc/cmdline)
 	else
 		cmdline=${KDUMP_COMMANDLINE}
 	fi
 
 	# These params should always be removed
-	cmdline=`remove_cmdline_param "$cmdline" crashkernel panic_on_warn`
+	cmdline=$(remove_cmdline_param "$cmdline" crashkernel panic_on_warn)
 	# These params can be removed configurably
-	cmdline=`remove_cmdline_param "$cmdline" ${KDUMP_COMMANDLINE_REMOVE}`
+	cmdline=$(remove_cmdline_param "$cmdline" ${KDUMP_COMMANDLINE_REMOVE})
 
 	# Always remove "root=X", as we now explicitly generate all kinds
-	# of dump target mount information including root fs. But we can
-	# not remove it in case of fadump or "default dump_to_rootfs".
+	# of dump target mount information including root fs.
 	#
 	# We do this before KDUMP_COMMANDLINE_APPEND, if one really cares
 	# about it(e.g. for debug purpose), then can pass "root=X" using
 	# KDUMP_COMMANDLINE_APPEND.
-	if [ $DEFAULT_DUMP_MODE != "fadump" ] && ! is_dump_to_rootfs; then
-		cmdline=`remove_cmdline_param "$cmdline" root`
-	fi
+	cmdline=$(remove_cmdline_param "$cmdline" root)
 
 	cmdline="${cmdline} ${KDUMP_COMMANDLINE_APPEND}"
 
-	id=`get_bootcpu_apicid`
+	id=$(get_bootcpu_apicid)
 	if [ ! -z ${id} ] ; then
-		cmdline=`append_cmdline "${cmdline}" disable_cpu_apicid ${id}`
+		cmdline=$(append_cmdline "${cmdline}" disable_cpu_apicid ${id})
 	fi
 
 	KDUMP_COMMANDLINE=$cmdline
diff --git a/mkdumprd b/mkdumprd
index 9f375e0..5342dac 100644
--- a/mkdumprd
+++ b/mkdumprd
@@ -448,6 +448,12 @@ then
     add_dracut_arg "--add-drivers" "$extra_modules"
 fi
 
+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().
+    is_dump_to_rootfs && add_mount "$(to_dev_name
$(get_root_fs_device))"
+fi
+
 dracut "${dracut_args[@]}" "$@"
 _rc=$?
 sync
-- 
1.8.3.1