udevadm Operations Resulting in Unmounted /proc and /sys?

udevadm Operations Resulting in Unmounted /proc and /sys?

[Scott Talbert]

Hello,

I am trying to investigate an issue that occurs during the upgrade of 
Ubuntu 9.10 to 10.04 that appears to occur when the root filesystem 
resides on a 'removable' device (ie, a flash drive).  Things seem to go 
wrong when one package's post-install script calls:

udevadm trigger --subsystem-match=block --action=change

After this command is issued, /proc and /sys appear to become unmounted 
somehow, and the upgrade fails due to not having /proc mounted.

Does anyone have any advice on how to investigate further why /proc and 
/sys are getting unmounted?

Thank you,
Scott Talbert

Re: udevadm Operations Resulting in Unmounted /proc and /sys?

[Kay Sievers]

On Fri, Jun 25, 2010 at 05:50, Scott Talbert <talbert@techie.net> wrote:
> I am trying to investigate an issue that occurs during the upgrade of Ubuntu
> 9.10 to 10.04 that appears to occur when the root filesystem resides on a
> 'removable' device (ie, a flash drive).  Things seem to go wrong when one
> package's post-install script calls:
>
> udevadm trigger --subsystem-match=block --action=change
>
> After this command is issued, /proc and /sys appear to become unmounted
> somehow, and the upgrade fails due to not having /proc mounted.
>
> Does anyone have any advice on how to investigate further why /proc and /sys
> are getting unmounted?

You better ask at an Ubuntu specific list or bugtracker. This is not a
known, or commonly possible behavior, and sound like some distribution
specific thing goes wrong here.

Kay

Re: udevadm Operations Resulting in Unmounted /proc and /sys?

[Martin Pitt]

Hello Scott,

Scott Talbert [2010-06-24 23:50 -0400]:
> udevadm trigger --subsystem-match=block --action=change
> 
> After this command is issued, /proc and /sys appear to become
> unmounted somehow

Please do "ubuntu-bug mountall" and attach the following information:

  * "udevadm monitor -e --udev" output while you manually do above
    trigger command
  * "mount" output before and after the command
  * /etc/fstab (just in case..)

We do not ship any udev patches compared to upstream (just some git
trunk cherrypicks), but udev is not really responsible for
mounting/unmounting in the first place. mountall is a plausible
candidate, but we can always reassign it to the correct package later
on.

Martin

-- 
Martin Pitt                        | http://www.piware.de
Ubuntu Developer (www.ubuntu.com)  | Debian Developer  (www.debian.org)

Re: udevadm Operations Resulting in Unmounted /proc and /sys?

[Scott Talbert]

Hi Martin,

On Fri, 25 Jun 2010, Martin Pitt wrote:

>> udevadm trigger --subsystem-match=block --action=change
>>
>> After this command is issued, /proc and /sys appear to become
>> unmounted somehow
>
> Please do "ubuntu-bug mountall" and attach the following information:
>
>  * "udevadm monitor -e --udev" output while you manually do above
>    trigger command
>  * "mount" output before and after the command
>  * /etc/fstab (just in case..)

This bug has already been reported here:
https://bugs.launchpad.net/ubuntu/+source/udisks/+bug/554718

I have added the information you requested.

Thanks,
Scott