no fsck for unmounted filesystems

[Reindl Harald]

Am 16.02.2015 um 12:47 schrieb Michael D. Setzer II:
> On 16 Feb 2015 at 11:30, Reindl Harald wrote:
>> /dev/sda1 is a ordinary partition containing only /boot
>> why does the kernel report it is in use?
>
> The kernel reports it as being mount

but why

> since it normally is as part of the boot process.

looks like you missed thed "for unmounted filesystems" in the subject

> /dev/sda1 is mount as /boot
> You can usually umount it if no one is in it , or actually using it
> umount /boot
>
> df will show the mounted partitions.
>
> umount /boot
> fsck /dev/sda1

i know that all *but* i did "umount /boot" and hence i expect to be able 
doing a fsck instead once again "touch /forcefsck" and reboot

otherwise the message would not be "/dev/sda1 is in use"
if it is mounted it's "/dev/sda1 is mounted"

so it is in use by whom and why after unmount?

>> if that would be true it could not be unmounted
>> ___________________________________________
>>
>> [root at asterisk:~]$ /usr/sbin/fsck.ext4 -f /dev/sda1
>> e2fsck 1.42.12 (29-Aug-2014)
>> /dev/sda1 is in use.
>> e2fsck: Cannot continue, aborting.
>> ___________________________________________
>>
>> [root at asterisk:~]$ lsof | grep /dev/sda1
>> [root at asterisk:~]$
>> ___________________________________________
>>
>> [root at asterisk:~]$ /usr/sbin/fsck.ext4 -n /dev/sda1
>> e2fsck 1.42.12 (29-Aug-2014)
>> Warning!  /dev/sda1 is in use.
>> boot was not cleanly unmounted, check forced.
>> Pass 1: Checking inodes, blocks, and sizes
>> Pass 2: Checking directory structure
>> Pass 3: Checking directory connectivity
>> Pass 4: Checking reference counts
>> Pass 5: Checking group summary information
>> Free blocks count wrong (454751, counted=469570).
>> Fix? no
>>
>> Free inodes count wrong (130215, counted=130220).
>> Fix? no
>>
>> boot: 345/130560 files (22.6% non-contiguous), 66464/521215 blocks