do not mount root twice

Resolves: bz821997

dracut will mount rootfs for us, so we need not pass root to fstab again here.
Here remove the root-mount line.

This will depends on the root=cmdline is right, by default kdump will
inherit it from /proc/cmdline.

Vivek: add document about the assumption for the root= cmdline issue.

Signed-off-by: Dave Young <dyoung@redhat.com>
Acked-by: Vivek Goyal <vgoyal@redhat.com>

kdump.sysconfig

@@ -7,6 +7,9 @@ KDUMP_KERNELVER=""
 # the kdump kernel.  This will likely match the contents of the grub kernel
 # line.  For example:
 #   KDUMP_COMMANDLINE="ro root=LABEL=/"
+# Dracut depends on proper root= options, so please make sure that appropriate
+# root= options are copied from /proc/cmdline. In general it is best to append
+# command line options using "KDUMP_COMMANDLINE_APPEND=".
 # If a command line is not specified, the default will be taken from
 # /proc/cmdline
 KDUMP_COMMANDLINE=""

kdump.sysconfig.i386

@@ -7,6 +7,9 @@ KDUMP_KERNELVER=""
 # the kdump kernel.  This will likely match the contents of the grub kernel
 # line.  For example:
 #   KDUMP_COMMANDLINE="ro root=LABEL=/"
+# Dracut depends on proper root= options, so please make sure that appropriate
+# root= options are copied from /proc/cmdline. In general it is best to append
+# command line options using "KDUMP_COMMANDLINE_APPEND=".
 # If a command line is not specified, the default will be taken from
 # /proc/cmdline
 KDUMP_COMMANDLINE=""

kdump.sysconfig.ppc64

@@ -7,6 +7,9 @@ KDUMP_KERNELVER=""
 # the kdump kernel.  This will likely match the contents of the grub kernel
 # line.  For example:
 #   KDUMP_COMMANDLINE="ro root=LABEL=/"
+# Dracut depends on proper root= options, so please make sure that appropriate
+# root= options are copied from /proc/cmdline. In general it is best to append
+# command line options using "KDUMP_COMMANDLINE_APPEND=".
 # If a command line is not specified, the default will be taken from
 # /proc/cmdline
 KDUMP_COMMANDLINE=""

kdump.sysconfig.s390x

@@ -7,6 +7,9 @@ KDUMP_KERNELVER=""
 # the kdump kernel.  This will likely match the contents of the grub kernel
 # line.  For example:
 #   KDUMP_COMMANDLINE="ro root=LABEL=/"
+# Dracut depends on proper root= options, so please make sure that appropriate
+# root= options are copied from /proc/cmdline. In general it is best to append
+# command line options using "KDUMP_COMMANDLINE_APPEND=".
 # If a command line is not specified, the default will be taken from
 # /proc/cmdline
 KDUMP_COMMANDLINE=""

kdump.sysconfig.x86_64

@@ -7,6 +7,9 @@ KDUMP_KERNELVER=""
 # the kdump kernel.  This will likely match the contents of the grub kernel
 # line.  For example:
 #   KDUMP_COMMANDLINE="ro root=LABEL=/"
+# Dracut depends on proper root= options, so please make sure that appropriate
+# root= options are copied from /proc/cmdline. In general it is best to append
+# command line options using "KDUMP_COMMANDLINE_APPEND=".
 # If a command line is not specified, the default will be taken from
 # /proc/cmdline
 KDUMP_COMMANDLINE=""

kexec-kdump-howto.txt

@@ -585,3 +585,13 @@ visible on the screen.  It does not work with all video cards however.
 Secondly, it may be worth trying to add vga15fb.ko to the extra_modules list in
 /etc/kdump.conf.  This will attempt to use the video card in framebuffer mode,
 which can blank the screen prior to the start of a dump capture.
+
+Notes on rootfs mount:
+Dracut is designed to mount rootfs by default. If rootfs mounting fails it
+will refuse to go on. So kdump leaves rootfs mounting to dracut currently.
+We make the assumtion that proper root= cmdline is being passed to dracut
+initramfs for the time being. If you need modify "KDUMP_COMMANDLINE=" in
+/etc/sysconfig/kdump, you will need to make sure that appropriate root=
+options are copied from /proc/cmdline. In general it is best to append
+command line options using "KDUMP_COMMANDLINE_APPEND=" instead of replacing
+the original command line completely.

mkdumprd

@@ -166,8 +166,6 @@ add_mount() {
     return 0
 }
 
-add_dracut_mount "$(to_mount "$(get_rootdev)")"
-
 # firstly get right SSH_KEY_LOCATION
 keyfile=$(awk '/sshkey/ {print $2}' $conf_file)
 if [ -f "$keyfile" ]; then