can't mount gfs on debian

["H.H. Ding" <hhding.gnu@gmail.com>]

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freecity:~# gfs_mkfs -t myhost:label -p lock_dlm -j 4 /dev/sda5
This will destroy any data on /dev/sda5.
It appears to contain a GFS filesystem.

Are you sure you want to proceed? [y/n] y

Device: /dev/sda5
Blocksize: 4096
Filesystem Size: 764476
Journals: 4
Resource Groups: 12
Locking Protocol: lock_dlm
Lock Table: myhost:label

Syncing...
All Done
freecity:~# mount -t gfs /dev/sda5 /mnt
mount: unknown filesystem type 'gfs'
freecity:~# grep -i gfs /boot/config-`uname -r`
# CONFIG_MAC80211_DEBUGFS is not set
CONFIG_GFS2_FS=m
CONFIG_GFS2_FS_LOCKING_NOLOCK=m
CONFIG_GFS2_FS_LOCKING_DLM=m
CONFIG_CONFIGFS_FS=m
freecity:~# lsmod | grep gfs
freecity:~# modprobe gfs2
freecity:~# modprobe gfs
FATAL: Module gfs not found.
freecity:~# mount -t gfs /dev/sda5 /mnt
mount: unknown filesystem type 'gfs'
freecity:~#
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