How to free up block device that is mounted to an inaccessible place?

Posted by Vi on Super User See other posts from Super User or by Vi
Published on 2011-01-03T23:00:40Z Indexed on 2011/01/03 23:55 UTC
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linux

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mount

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umount

root@vi-notebook:~# cat /proc/mounts | grep raidy
/dev/md0 /root/e/i/wpc2/boot/mnt/raidy reiserfs ro,nosuid,nodev,noexec,noatime 0 0

root@vi-notebook:~# umount -n /root/e/i/wpc2/boot/mnt/raidy
umount: /root/e/i/wpc2/boot/mnt/raidy: Transport endpoint is not connected

root@vi-notebook:~# mount /dev/md/raidy /mnt/raidy/ -t reiserfs -o nodev,nosuid,noexec,acl,noatime
mount: /dev/md0 already mounted or /mnt/raidy/ busy

The only workaround I found is:

root@vi-notebook:~# losetup /dev/loop0 /dev/md/raidy 
root@vi-notebook:~# mount /dev/loop0 /mnt/raidy/ -t reiserfs -o nodev,nosuid,noexec,acl,noatime

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