Don't mount the dump target unless needed

For fadump, this helps to reduce the risk of boot failure, and
may also help speed up the boot by a bit.

For normal kdump, this will delay the dump target mounting, and no
longer depend on systemd to do the mounting job.

And currently there is a failure that caused by some mount handling
bug with kernel and systemd that is failing the system booting:

[FAILED] Failed to mount /kdumproot/home.
See 'systemctl status kdumproot-home.mount' for details.
[DEPEND] Dependency failed for Local File Systems.
[  OK  ] Reached target Remote File Systems (Pre).
[  OK  ] Reached target Remote File Systems.
         Starting udev Coldplug all Devices...
         Starting Create Volatile Files and Directories...
         Starting Kdump Emergency...

This patch can bypass it. The fix of root cause is still WIP, but this
patch itself is a nice to have optimization so it's reasonable to do so.

Signed-off-by: Kairui Song <kasong@redhat.com>
Acked-by: Pingfan Liu <piliu@redhat.com>
This commit is contained in:
Kairui Song 2019-09-27 18:17:32 +08:00
parent 367ca85d1f
commit 6dee286467
2 changed files with 28 additions and 7 deletions

View File

@ -96,16 +96,31 @@ get_kdump_confs()
# dump_fs <mount point| device> # dump_fs <mount point| device>
dump_fs() dump_fs()
{ {
local _do_umount=""
local _dev=$(findmnt -k -f -n -r -o SOURCE $1) local _dev=$(findmnt -k -f -n -r -o SOURCE $1)
local _mp=$(findmnt -k -f -n -r -o TARGET $1) local _mp=$(findmnt -k -f -n -r -o TARGET $1)
local _op=$(findmnt -k -f -n -r -o OPTIONS $1) local _op=$(findmnt -k -f -n -r -o OPTIONS $1)
echo "kdump: dump target is $_dev"
if [ -z "$_mp" ]; then if [ -z "$_mp" ]; then
echo "kdump: error: Dump target $_dev is not mounted." _dev=$(findmnt -s -f -n -r -o SOURCE $1)
return 1 _mp=$(findmnt -s -f -n -r -o TARGET $1)
_op=$(findmnt -s -f -n -r -o OPTIONS $1)
if [ -n "$_dev" ] && [ -n "$_mp" ]; then
echo "kdump: dump target $_dev is not mounted, trying to mount..."
mkdir -p $_mp
mount -o $_op $_dev $_mp
if [ $? -ne 0 ]; then
echo "kdump: mounting failed (mount point: $_mp, option: $_op)"
return 1
fi
_do_umount=1
else
echo "kdump: error: Dump target $_dev is not usable"
fi
else
echo "kdump: dump target is $_dev"
fi fi
# Remove -F in makedumpfile case. We don't want a flat format dump here. # Remove -F in makedumpfile case. We don't want a flat format dump here.
@ -129,6 +144,11 @@ dump_fs()
sync sync
echo "kdump: saving vmcore complete" echo "kdump: saving vmcore complete"
if [ $_do_umount ]; then
umount $_mp || echo "kdump: warn: failed to umount target"
fi
# improper kernel cmdline can cause the failure of echo, we can ignore this kind of failure # improper kernel cmdline can cause the failure of echo, we can ignore this kind of failure
return 0 return 0
} }

View File

@ -108,12 +108,13 @@ to_mount() {
fi fi
# mount fs target as rw in 2nd kernel # mount fs target as rw in 2nd kernel
_options=$(echo $_options | sed 's/\(^\|,\)ro\($\|,\)/\1rw\2/g') _options=$(echo $_options | sed 's/\(^\|,\)ro\($\|,\)/\1rw\2/g')
# with 'noauto' in fstab nfs and non-root disk mount will fail in 2nd # filter out 'noauto' here, it will be force appended later, avoid duplication
# kernel, filter it out here.
_options=$(echo $_options | sed 's/\(^\|,\)noauto\($\|,\)/\1/g') _options=$(echo $_options | sed 's/\(^\|,\)noauto\($\|,\)/\1/g')
# drop nofail or nobootwait # drop nofail or nobootwait
_options=$(echo $_options | sed 's/\(^\|,\)nofail\($\|,\)/\1/g') _options=$(echo $_options | sed 's/\(^\|,\)nofail\($\|,\)/\1/g')
_options=$(echo $_options | sed 's/\(^\|,\)nobootwait\($\|,\)/\1/g') _options=$(echo $_options | sed 's/\(^\|,\)nobootwait\($\|,\)/\1/g')
# only mount the dump target when needed.
_options="$_options,noauto"
_mntopts="$_target $_fstype $_options" _mntopts="$_target $_fstype $_options"
#for non-nfs _dev converting to use udev persistent name #for non-nfs _dev converting to use udev persistent name