umount -a

umount -a

[Bruce Dubbs]

At linuxfromscratch, we've just made some changes to write bootscript 
messages to /run/var.  This seems to work fine for us until shutdown where

   umaount -a

unmounts /run which is mounted as a tmpfs.  We can certainly work around 
the problem, but was wondering if this issue may also affect others.

The man page for umount says:

  -a     All of the file systems described in /etc/mtab are unmounted.
(With umount version 2.7 and later: the proc filesystem is not
unmounted.)

Would it be reasonable to change umount -a to also omit /run if it is 
mounted as a tmpfs?

   -- Bruce

Re: umount -a

[Mike Frysinger]

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On Tuesday, August 02, 2011 17:54:56 Bruce Dubbs wrote:
> At linuxfromscratch, we've just made some changes to write bootscript
> messages to /run/var.  This seems to work fine for us until shutdown where
> 
>    umaount -a
> 
> unmounts /run which is mounted as a tmpfs.  We can certainly work around
> the problem, but was wondering if this issue may also affect others.

you could make the same argument for /dev, but i dont think that gets handled 
specially either.  plus, there's the whole "will only work with recent util-
linux versions".  so it makes sense imo to have distro init code to deal with 
this regardless of anything else.
-mike

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Re: umount -a

[Karel Zak]

On Tue, Aug 02, 2011 at 04:54:56PM -0500, Bruce Dubbs wrote:
> At linuxfromscratch, we've just made some changes to write bootscript  
> messages to /run/var.  This seems to work fine for us until shutdown 
> where
>
>   umaount -a
>
> unmounts /run which is mounted as a tmpfs.  We can certainly work around  
> the problem, but was wondering if this issue may also affect others.
>
> The man page for umount says:
>
>  -a     All of the file systems described in /etc/mtab are unmounted.
> (With umount version 2.7 and later: the proc filesystem is not
> unmounted.)
>
> Would it be reasonable to change umount -a to also omit /run if it is  
> mounted as a tmpfs?

 umount -a -t notmpfs  ?

    Karel

-- 
 Karel Zak  <kzak@redhat.com>
 http://karelzak.blogspot.com

Re: umount -a

[Tom Gundersen]

On Mon, Aug 8, 2011 at 10:54 AM, Karel Zak <kzak@redhat.com> wrote:
>> Would it be reasonable to change umount -a to also omit /run if it is
>> mounted as a tmpfs?
>
>  umount -a -t notmpfs  ?

This might not work as intended if you have a tmpfs mounted on top of
a regular fs (in which case you would like to unmount them both).

I think the correct solution is to do as dracut and have a shutdown
ramfs from where you can unmount rootfs and all its mountpoints.

Cheers,

-t