1:44 a.m.
When a remote dump target is specified, kdump dracut module prefixes
'kdump-' to network interface name (ifname) as kernel assigned names
are not persistent. In fadump mode, kdump dracut module is added to
the default initrd, which adds the 'kdump-' prefix to the ifname of
the prodcution kernel itself. If fadump mode is disabled after this,
kdump dracut module picks the ifname that is already prefixed with
'kdump-' in the production kernel and adds another 'kdump-' to it,
making the ifname something like kdump-kdump-eth0 for kdump kernel.
Eventually, kdump kernel fails with below traces:
dracut-initqueue[246]: RTNETLINK answers: Network is unreachable
dracut-initqueue[246]: arping: Device kdump-kdump-eth0 not available.
The ip command shows the below:
kdump:/# ip addr show kdump-kdump-eth0
2: kdump-kdump-eth: <BROADCAST,MULTICAST,UP,LOWER_UP> mtu 1500 \
qdisc pfifo_fast state UNKNOWN qlen 1000
link/ether 22:82:87:7b:98:02 brd ff:ff:ff:ff:ff:ff
inet6 2002:903:15f:550:2082:87ff:fe7b:9802/64 scope global \
mngtmpaddr dynamic
valid_lft 2591890sec preferred_lft 604690sec
inet6 fe80::2082:87ff:fe7b:9802/64 scope link
valid_lft forever preferred_lft forever
kdump:/#
The trailing 0 from kdump-kdump-eth0 is missing in the ifname, probably
truncated owing to ifname length limit, while setting.
This patch fixes this by avoiding addition of the prefix 'kdump-' when
such prefix is already present in the ifname.
Signed-off-by: Hari Bathini <hbathini(a)linux.vnet.ibm.com>
---
Changes from v2:
* Added a comment mentioning why this is needed.
dracut-module-setup.sh | 6 +++++-
1 file changed, 5 insertions(+), 1 deletion(-)
diff --git a/dracut-module-setup.sh b/dracut-module-setup.sh
index 68e0ff8..0baffaa 100755
--- a/dracut-module-setup.sh
+++ b/dracut-module-setup.sh
@@ -161,7 +161,11 @@ kdump_get_perm_addr() {
kdump_setup_ifname() {
local _ifname
- if [[ $1 =~ eth* ]]; then
+ # If ifname already has 'kdump-' prefix, we must be switching from
+ # fadump to kdump. Skip prefixing 'kdump-' in this case as adding
+ # another prefix may truncate the ifname. Since an ifname with
+ # 'kdump-' is already persistent, this should be fine.
+ if [[ $1 =~ eth* ]] && [[ ! $1 =~ ^kdump-* ]]; then
_ifname="kdump-$1"
else
_ifname="$1"
1:44 a.m.
New subject: [PATCH v3 2/2] fadump: restore default initrd when fadump mode is
disabled
When fadump mode is enabled, the default initrd is rebuilt with kdump
dracut module. As the default initrd is altered, the original default
initrd is backed up. But we are not restoring it when fadump mode is
disabled. This patch tries to restore the backed up default initrd on
disabling fadump mode.
Signed-off-by: Hari Bathini <hbathini(a)linux.vnet.ibm.com>
---
Changes from v2:
* Using `uname -r` for kernel version instead of $kdump-kver
for fadump.
* Detecting mode switch and rebuilding initrd
kdumpctl | 78 +++++++++++++++++++++++++++++++++++++++++++++-----------------
1 file changed, 57 insertions(+), 21 deletions(-)
diff --git a/kdumpctl b/kdumpctl
index d0bbb55..a7f968b 100755
--- a/kdumpctl
+++ b/kdumpctl
@@ -9,6 +9,8 @@ MKDUMPRD="/sbin/mkdumprd -f"
SAVE_PATH=/var/crash
SSH_KEY_LOCATION="/root/.ssh/kdump_id_rsa"
DUMP_TARGET=""
+DEFAULT_INITRD=""
+DEFAULT_INITRD_BAK=""
TARGET_INITRD=""
FADUMP_ENABLED_SYS_NODE="/sys/kernel/fadump_enabled"
FADUMP_REGISTER_SYS_NODE="/sys/kernel/fadump_registered"
@@ -154,9 +156,6 @@ rebuild_fadump_initrd()
{
local target_initrd_tmp
- # backup fadump initrd for reference before replacing it
- backup_initrd
-
# this file tells the initrd is fadump enabled
touch /tmp/fadump.initramfs
target_initrd_tmp="$TARGET_INITRD.tmp"
@@ -190,8 +189,17 @@ rebuild_kdump_initrd()
rebuild_initrd()
{
if [ $DEFAULT_DUMP_MODE == "fadump" ]; then
+ # backup initrd for reference before replacing it
+ # with fadump aware initrd
+ backup_default_initrd
+
rebuild_fadump_initrd
else
+ # check if a backup of default initrd exists. If yes,
+ # it signifies a switch from fadump mode. So, restore
+ # the backed up default initrd.
+ restore_default_initrd
+
rebuild_kdump_initrd
fi
@@ -220,15 +228,25 @@ check_executable()
done
}
-backup_initrd()
+backup_default_initrd()
{
- local target_initrd_bak
+ if [ ! -e $DEFAULT_INITRD_BAK ]; then
+ echo "Backing up $DEFAULT_INITRD before rebuild."
+ cp $DEFAULT_INITRD $DEFAULT_INITRD_BAK
+ fi
+}
- # Check if backup initrd is already present.
- target_initrd_bak="$TARGET_INITRD.bak"
- if [ ! -e $target_initrd_bak ];then
- echo "Backing up $TARGET_INITRD"
- cp $TARGET_INITRD $target_initrd_bak
+restore_default_initrd()
+{
+ # If a backup initrd exists, we must be switching back from
+ # fadump to kdump. Restore the original default initrd.
+ if [ -f $DEFAULT_INITRD_BAK ];then
+ mv $DEFAULT_INITRD_BAK $DEFAULT_INITRD
+ if [[ $? -eq 0 ]]; then
+ echo -n "Restoring original initrd as fadump mode "
+ echo "is disabled."
+ sync
+ fi
fi
}
@@ -320,10 +338,12 @@ check_boot_dir()
fi
}
-setup_target_initrd()
+setup_initrd()
{
+ DEFAULT_INITRD="${KDUMP_BOOTDIR}/initramfs-`uname -r`.img"
+ DEFAULT_INITRD_BAK="${KDUMP_BOOTDIR}/.initramfs-`uname -r`.img.default"
if [ $DEFAULT_DUMP_MODE == "fadump" ]; then
- TARGET_INITRD="${KDUMP_BOOTDIR}/initramfs-${kdump_kver}.img"
+ TARGET_INITRD="$DEFAULT_INITRD"
if [ ! -s "$TARGET_INITRD" ]; then
echo "Error: No initrd found to rebuild!"
return 1
@@ -504,7 +524,6 @@ check_rebuild()
local extra_modules
local _force_rebuild force_rebuild="0"
local ret system_modified="0"
- local initramfs_has_fadump
check_boot_dir
@@ -515,7 +534,7 @@ check_rebuild()
fi
kdump_kernel="${KDUMP_BOOTDIR}/${KDUMP_IMG}-${kdump_kver}${KDUMP_IMG_EXT}"
- setup_target_initrd
+ setup_initrd
if [ $? -ne 0 ]; then
return 1
fi
@@ -547,15 +566,10 @@ check_rebuild()
system_modified="1"
fi
- #check if target initrd has fadump support
- if [ "$DEFAULT_DUMP_MODE" = "fadump" ] && [ -f
"$TARGET_INITRD" ]; then
- initramfs_has_fadump=`lsinitrd -m $TARGET_INITRD | grep ^kdumpbase$ | wc -l`
- fi
-
if [ $image_time -eq 0 ]; then
echo -n "No kdump initial ramdisk found."; echo
- elif [ $DEFAULT_DUMP_MODE == "fadump" ] && [
"$initramfs_has_fadump" -eq "0" ]; then
- echo "$TARGET_INITRD has no fadump support"
+ elif is_mode_switched; then
+ echo -n "Dump mode changed from last boot."; echo
elif [ "$force_rebuild" != "0" ]; then
echo -n "Force rebuild $TARGET_INITRD"; echo
elif [ "$system_modified" != "0" ]; then
@@ -714,6 +728,28 @@ propagate_ssh_key()
fi
}
+is_mode_switched()
+{
+ local _mod_included
+
+ # find if default initrd has kdumpbase module included.
+ _mod_included=`lsinitrd -m $DEFAULT_INITRD | grep ^kdumpbase$ | wc -l`
+
+ if [ "$DEFAULT_DUMP_MODE" != "fadump" ]; then
+ # If kdumpbase module is included in default initrd,
+ # we must have just switched from fadump mode.
+ if [ "$_mod_included" -eq "1" ]; then
+ return 0
+ fi
+ elif [ "$_mod_included" -eq "0" ]; then
+ # If kdumpbase module is missing in default initrd,
+ # we must have just switched from kdump mode.
+ return 0
+ fi
+
+ return 1
+}
+
is_fadump_capable()
{
# Check if firmware-assisted dump is enabled
2:19 a.m.
New subject: [PATCH v3 2/2] fadump: restore default initrd when fadump mode
is disabled
Hi Hari,
On 10/17/16 at 12:14pm, Hari Bathini wrote:
When fadump mode is enabled, the default initrd is rebuilt with
kdump
dracut module. As the default initrd is altered, the original default
initrd is backed up. But we are not restoring it when fadump mode is
disabled. This patch tries to restore the backed up default initrd on
disabling fadump mode.
Signed-off-by: Hari Bathini <hbathini(a)linux.vnet.ibm.com>
---
Changes from v2:
* Using `uname -r` for kernel version instead of $kdump-kver
for fadump.
* Detecting mode switch and rebuilding initrd
kdumpctl | 78 +++++++++++++++++++++++++++++++++++++++++++++-----------------
1 file changed, 57 insertions(+), 21 deletions(-)
diff --git a/kdumpctl b/kdumpctl
index d0bbb55..a7f968b 100755
--- a/kdumpctl
+++ b/kdumpctl
@@ -9,6 +9,8 @@ MKDUMPRD="/sbin/mkdumprd -f"
SAVE_PATH=/var/crash
SSH_KEY_LOCATION="/root/.ssh/kdump_id_rsa"
DUMP_TARGET=""
+DEFAULT_INITRD=""
+DEFAULT_INITRD_BAK=""
TARGET_INITRD=""
FADUMP_ENABLED_SYS_NODE="/sys/kernel/fadump_enabled"
FADUMP_REGISTER_SYS_NODE="/sys/kernel/fadump_registered"
@@ -154,9 +156,6 @@ rebuild_fadump_initrd()
{
local target_initrd_tmp
- # backup fadump initrd for reference before replacing it
- backup_initrd
-
# this file tells the initrd is fadump enabled
touch /tmp/fadump.initramfs
target_initrd_tmp="$TARGET_INITRD.tmp"
@@ -190,8 +189,17 @@ rebuild_kdump_initrd()
rebuild_initrd()
{
if [ $DEFAULT_DUMP_MODE == "fadump" ]; then
+ # backup initrd for reference before replacing it
+ # with fadump aware initrd
+ backup_default_initrd
+
rebuild_fadump_initrd
else
+ # check if a backup of default initrd exists. If yes,
+ # it signifies a switch from fadump mode. So, restore
+ # the backed up default initrd.
+ restore_default_initrd
I'm not sure if it is good to add the logic in normal path. Could we
move it to somewhere like is_mode_switched (but the function seems to be
for a bool value ..)? But it should be limited to fadump -> kdump &&
default initrd contains 99kdumpbase module. The reason is I worry about
user have copied the initrd as same file name as what fadump uses then
if we overwrite the old initrd it might fail to boot..
OTOH, if we can have fadump code in its own function or if/else branch
it will be better.
+
rebuild_kdump_initrd
fi
@@ -220,15 +228,25 @@ check_executable()
done
}
-backup_initrd()
+backup_default_initrd()
{
- local target_initrd_bak
+ if [ ! -e $DEFAULT_INITRD_BAK ]; then
+ echo "Backing up $DEFAULT_INITRD before rebuild."
+ cp $DEFAULT_INITRD $DEFAULT_INITRD_BAK
There should be a error checking here, consider cp failed it will still
leave a partial backup initrd.
+ fi
+}
- # Check if backup initrd is already present.
- target_initrd_bak="$TARGET_INITRD.bak"
- if [ ! -e $target_initrd_bak ];then
- echo "Backing up $TARGET_INITRD"
- cp $TARGET_INITRD $target_initrd_bak
+restore_default_initrd()
+{
+ # If a backup initrd exists, we must be switching back from
+ # fadump to kdump. Restore the original default initrd.
+ if [ -f $DEFAULT_INITRD_BAK ];then
+ mv $DEFAULT_INITRD_BAK $DEFAULT_INITRD
+ if [[ $? -eq 0 ]]; then
+ echo -n "Restoring original initrd as fadump mode "
+ echo "is disabled."
+ sync
+ fi
fi
}
@@ -320,10 +338,12 @@ check_boot_dir()
fi
}
-setup_target_initrd()
+setup_initrd()
{
+ DEFAULT_INITRD="${KDUMP_BOOTDIR}/initramfs-`uname -r`.img"
+ DEFAULT_INITRD_BAK="${KDUMP_BOOTDIR}/.initramfs-`uname -r`.img.default"
if [ $DEFAULT_DUMP_MODE == "fadump" ]; then
- TARGET_INITRD="${KDUMP_BOOTDIR}/initramfs-${kdump_kver}.img"
+ TARGET_INITRD="$DEFAULT_INITRD"
if [ ! -s "$TARGET_INITRD" ]; then
echo "Error: No initrd found to rebuild!"
return 1
@@ -504,7 +524,6 @@ check_rebuild()
local extra_modules
local _force_rebuild force_rebuild="0"
local ret system_modified="0"
- local initramfs_has_fadump
check_boot_dir
@@ -515,7 +534,7 @@ check_rebuild()
fi
kdump_kernel="${KDUMP_BOOTDIR}/${KDUMP_IMG}-${kdump_kver}${KDUMP_IMG_EXT}"
- setup_target_initrd
+ setup_initrd
if [ $? -ne 0 ]; then
return 1
fi
@@ -547,15 +566,10 @@ check_rebuild()
system_modified="1"
fi
- #check if target initrd has fadump support
- if [ "$DEFAULT_DUMP_MODE" = "fadump" ] && [ -f
"$TARGET_INITRD" ]; then
- initramfs_has_fadump=`lsinitrd -m $TARGET_INITRD | grep ^kdumpbase$ | wc -l`
- fi
-
if [ $image_time -eq 0 ]; then
echo -n "No kdump initial ramdisk found."; echo
- elif [ $DEFAULT_DUMP_MODE == "fadump" ] && [
"$initramfs_has_fadump" -eq "0" ]; then
- echo "$TARGET_INITRD has no fadump support"
+ elif is_mode_switched; then
+ echo -n "Dump mode changed from last boot."; echo
elif [ "$force_rebuild" != "0" ]; then
echo -n "Force rebuild $TARGET_INITRD"; echo
elif [ "$system_modified" != "0" ]; then
@@ -714,6 +728,28 @@ propagate_ssh_key()
fi
}
+is_mode_switched()
+{
+ local _mod_included
+
+ # find if default initrd has kdumpbase module included.
+ _mod_included=`lsinitrd -m $DEFAULT_INITRD | grep ^kdumpbase$ | wc -l`
+
+ if [ "$DEFAULT_DUMP_MODE" != "fadump" ]; then
+ # If kdumpbase module is included in default initrd,
+ # we must have just switched from fadump mode.
+ if [ "$_mod_included" -eq "1" ]; then
+ return 0
+ fi
+ elif [ "$_mod_included" -eq "0" ]; then
+ # If kdumpbase module is missing in default initrd,
+ # we must have just switched from kdump mode.
+ return 0
+ fi
+
+ return 1
+}
+
is_fadump_capable()
{
# Check if firmware-assisted dump is enabled
_______________________________________________
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Thanks
Dave
2:42 a.m.
New subject: [PATCH v3 2/2] fadump: restore default initrd when fadump mode
is disabled
On 10/20/16 at 03:19pm, Dave Young wrote:
Hi Hari,
On 10/17/16 at 12:14pm, Hari Bathini wrote:
> When fadump mode is enabled, the default initrd is rebuilt with kdump
> dracut module. As the default initrd is altered, the original default
> initrd is backed up. But we are not restoring it when fadump mode is
> disabled. This patch tries to restore the backed up default initrd on
> disabling fadump mode.
>
> Signed-off-by: Hari Bathini <hbathini(a)linux.vnet.ibm.com>
> ---
>
> Changes from v2:
> * Using `uname -r` for kernel version instead of $kdump-kver
> for fadump.
> * Detecting mode switch and rebuilding initrd
>
>
> kdumpctl | 78 +++++++++++++++++++++++++++++++++++++++++++++-----------------
> 1 file changed, 57 insertions(+), 21 deletions(-)
>
> diff --git a/kdumpctl b/kdumpctl
> index d0bbb55..a7f968b 100755
> --- a/kdumpctl
> +++ b/kdumpctl
> @@ -9,6 +9,8 @@ MKDUMPRD="/sbin/mkdumprd -f"
> SAVE_PATH=/var/crash
> SSH_KEY_LOCATION="/root/.ssh/kdump_id_rsa"
> DUMP_TARGET=""
> +DEFAULT_INITRD=""
> +DEFAULT_INITRD_BAK=""
> TARGET_INITRD=""
> FADUMP_ENABLED_SYS_NODE="/sys/kernel/fadump_enabled"
> FADUMP_REGISTER_SYS_NODE="/sys/kernel/fadump_registered"
> @@ -154,9 +156,6 @@ rebuild_fadump_initrd()
> {
> local target_initrd_tmp
>
> - # backup fadump initrd for reference before replacing it
> - backup_initrd
> -
> # this file tells the initrd is fadump enabled
> touch /tmp/fadump.initramfs
> target_initrd_tmp="$TARGET_INITRD.tmp"
> @@ -190,8 +189,17 @@ rebuild_kdump_initrd()
> rebuild_initrd()
> {
> if [ $DEFAULT_DUMP_MODE == "fadump" ]; then
> + # backup initrd for reference before replacing it
> + # with fadump aware initrd
> + backup_default_initrd
> +
> rebuild_fadump_initrd
> else
> + # check if a backup of default initrd exists. If yes,
> + # it signifies a switch from fadump mode. So, restore
> + # the backed up default initrd.
> + restore_default_initrd
I'm not sure if it is good to add the logic in normal path. Could we
move it to somewhere like is_mode_switched (but the function seems to be
for a bool value ..)? But it should be limited to fadump -> kdump &&
default initrd contains 99kdumpbase module. The reason is I worry about
user have copied the initrd as same file name as what fadump uses then
if we overwrite the old initrd it might fail to boot..
Even if we only restore it when default initd includes kdumpbase module
we still do not know if the backuped initrd is correct. Can we verify it
before restoring? Save the md5 sum somewhere?
>
> OTOH, if we can have fadump code in its own function or if/else branch
> it will be better.
>
> > +
> > rebuild_kdump_initrd
> > fi
> >
> > @@ -220,15 +228,25 @@ check_executable()
> > done
> > }
> >
> > -backup_initrd()
> > +backup_default_initrd()
> > {
> > - local target_initrd_bak
> > + if [ ! -e $DEFAULT_INITRD_BAK ]; then
> > + echo "Backing up $DEFAULT_INITRD before rebuild."
> > + cp $DEFAULT_INITRD $DEFAULT_INITRD_BAK
>
> There should be a error checking here, consider cp failed it will still
> leave a partial backup initrd.
>
> > + fi
> > +}
> >
> > - # Check if backup initrd is already present.
> > - target_initrd_bak="$TARGET_INITRD.bak"
> > - if [ ! -e $target_initrd_bak ];then
> > - echo "Backing up $TARGET_INITRD"
> > - cp $TARGET_INITRD $target_initrd_bak
> > +restore_default_initrd()
> > +{
> > + # If a backup initrd exists, we must be switching back from
> > + # fadump to kdump. Restore the original default initrd.
> > + if [ -f $DEFAULT_INITRD_BAK ];then
> > + mv $DEFAULT_INITRD_BAK $DEFAULT_INITRD
> > + if [[ $? -eq 0 ]]; then
> > + echo -n "Restoring original initrd as fadump mode "
> > + echo "is disabled."
> > + sync
> > + fi
> > fi
> > }
> >
> > @@ -320,10 +338,12 @@ check_boot_dir()
> > fi
> > }
> >
> > -setup_target_initrd()
> > +setup_initrd()
> > {
> > + DEFAULT_INITRD="${KDUMP_BOOTDIR}/initramfs-`uname -r`.img"
> > + DEFAULT_INITRD_BAK="${KDUMP_BOOTDIR}/.initramfs-`uname
-r`.img.default"
> > if [ $DEFAULT_DUMP_MODE == "fadump" ]; then
> > - TARGET_INITRD="${KDUMP_BOOTDIR}/initramfs-${kdump_kver}.img"
> > + TARGET_INITRD="$DEFAULT_INITRD"
> > if [ ! -s "$TARGET_INITRD" ]; then
> > echo "Error: No initrd found to rebuild!"
> > return 1
> > @@ -504,7 +524,6 @@ check_rebuild()
> > local extra_modules
> > local _force_rebuild force_rebuild="0"
> > local ret system_modified="0"
> > - local initramfs_has_fadump
> >
> > check_boot_dir
> >
> > @@ -515,7 +534,7 @@ check_rebuild()
> > fi
> >
> >
kdump_kernel="${KDUMP_BOOTDIR}/${KDUMP_IMG}-${kdump_kver}${KDUMP_IMG_EXT}"
> > - setup_target_initrd
> > + setup_initrd
> > if [ $? -ne 0 ]; then
> > return 1
> > fi
> > @@ -547,15 +566,10 @@ check_rebuild()
> > system_modified="1"
> > fi
> >
> > - #check if target initrd has fadump support
> > - if [ "$DEFAULT_DUMP_MODE" = "fadump" ] && [ -f
"$TARGET_INITRD" ]; then
> > - initramfs_has_fadump=`lsinitrd -m $TARGET_INITRD | grep ^kdumpbase$ | wc -l`
> > - fi
> > -
> > if [ $image_time -eq 0 ]; then
> > echo -n "No kdump initial ramdisk found."; echo
> > - elif [ $DEFAULT_DUMP_MODE == "fadump" ] && [
"$initramfs_has_fadump" -eq "0" ]; then
> > - echo "$TARGET_INITRD has no fadump support"
> > + elif is_mode_switched; then
> > + echo -n "Dump mode changed from last boot."; echo
> > elif [ "$force_rebuild" != "0" ]; then
> > echo -n "Force rebuild $TARGET_INITRD"; echo
> > elif [ "$system_modified" != "0" ]; then
> > @@ -714,6 +728,28 @@ propagate_ssh_key()
> > fi
> > }
> >
> > +is_mode_switched()
> > +{
> > + local _mod_included
> > +
> > + # find if default initrd has kdumpbase module included.
> > + _mod_included=`lsinitrd -m $DEFAULT_INITRD | grep ^kdumpbase$ | wc -l`
> > +
> > + if [ "$DEFAULT_DUMP_MODE" != "fadump" ]; then
> > + # If kdumpbase module is included in default initrd,
> > + # we must have just switched from fadump mode.
> > + if [ "$_mod_included" -eq "1" ]; then
> > + return 0
> > + fi
> > + elif [ "$_mod_included" -eq "0" ]; then
> > + # If kdumpbase module is missing in default initrd,
> > + # we must have just switched from kdump mode.
> > + return 0
> > + fi
> > +
> > + return 1
> > +}
> > +
> > is_fadump_capable()
> > {
> > # Check if firmware-assisted dump is enabled
> > _______________________________________________
> > kexec mailing list -- kexec(a)lists.fedoraproject.org
> > To unsubscribe send an email to kexec-leave(a)lists.fedoraproject.org
>
> Thanks
> Dave
> _______________________________________________
> kexec mailing list -- kexec(a)lists.fedoraproject.org
> To unsubscribe send an email to kexec-leave(a)lists.fedoraproject.org
2739
days inactive
2742
days old
3 comments
2 participants
participants (2)
-
Dave Young -
Hari Bathini