bugutil-vserver - Bugs: bug #25547, mounting /sbin readonly remounts...

 
 

You are not allowed to post comments on this tracker with your current authentication level.

bug #25547: mounting /sbin readonly remounts whole partition readonly

Submitted by:  Andreas <medic>
Submitted on:  Tue 10 Feb 2009 02:23:41 PM UTC  
 
Category: NoneSeverity: 3 - Normal
Item Group: NoneStatus: Ready For Test
Privacy: PublicAssigned to: Daniel Hokka Zakrisson <daniel_hozac>
Open/Closed: OpenComponent Version: stable
Release: 0.30.216

(Jump to the original submission Jump to the original submission)

Fri 24 Apr 2009 08:32:55 AM UTC, comment #6:

we ported Your patch down and applied it to the current debian version.

We weren't able to reproduce any of the problems we had lately.

We are rolling this patch out to production environment now.
Thank You alot

Andreas <medic>
Fri 03 Apr 2009 05:01:37 PM UTC, comment #5:

i just had a look at your patch, and i spawned an idea.
We had lately big issues when restarting vserver often due to config changes, resulting in having secure mount taking all cpu power of all 16 cores ... not accepting a kill -9, nor were we able to force-remount via sysreq.

i got the impression, there could be a kind of deadlock between secure_mount, the kernel and pd_flush, which stated to wait for IO all the time.

my colleague stated, he would have noticed that at his servers too, when using vserver and mount --bind.

Could this be a side-effect of this mount-problem ?

Andreas <medic>
Fri 03 Apr 2009 04:42:01 PM UTC, comment #4:

No, the problem is with the way bind mounts with different attributes from the original mount point are handled in recent kernels. This should be fixed by commit 2832.

Daniel Hokka Zakrisson <daniel_hozac>
Project MemberIn charge of this item.
Fri 03 Apr 2009 03:56:34 PM UTC, comment #3:

I found the bug - this costs someone a case of beer ;)

It's a parser bug regarding reading fstab-parsing.

1st) the last entry in fstab when doing read-only-bind(only?)-mounts has to be "rw", otherwise

laura:/srv/vserver# touch test
laura:/srv/vserver# vserver vs-p49couk start
secure-mount: open(<mtab>): Read-only file system
Failed to update mtab-file
secure-mount: open(<mtab>): Read-only file system
Failed to update mtab-file
secure-mount: open(<mtab>): Read-only file system
Failed to update mtab-file
secure-mount: open(<mtab>): Read-only file system
Failed to update mtab-file
secure-mount: open(<mtab>): Read-only file system
Failed to update mtab-file
secure-mount: write(): Invalid argument
Failed to update mtab-file
secure-mount: write(): Invalid argument
Failed to update mtab-file
chroot-sh: unlink("var/run/lighttpd.pid"): Read-only file system
chroot-sh: unlink("var/run/crond.reboot"): Read-only file system
chroot-sh: unlink("var/run/crond.pid"): Read-only file system
chroot-sh: unlink("var/run/utmp"): Read-only file system

Failed to start vserver 'vs-p49couk'
laura:/srv/vserver# touch test
touch: can't touch „test“: Filesystem is read-only

It is only reproducible, if NOT already a vserver is running.
If any vserver is already running, it will start as expected.
If not - one ends up with these errors.

Andreas <medic>
Fri 03 Apr 2009 02:06:05 PM UTC, comment #2:

It's standard lenny kernel

Linux atlas 2.6.26-1-vserver-amd64 #1 SMP Fri Mar 13 20:19:13 UTC 2009 x86_64 GNU/Linux

Andreas <medic>
Thu 26 Mar 2009 06:02:35 PM UTC, comment #1:

What kernel is that on?

Daniel Hokka Zakrisson <daniel_hozac>
Project MemberIn charge of this item.
Tue 10 Feb 2009 02:23:41 PM UTC, original submission:

Our setup is:
- LVM partition which holds the vserver-data
- a stripped vserver, which mount-binds everything needed to start readonly
- a complete vserver serving as reference.

when /sbin in /etc/vserver/<vserver>/fstab is "bind,ro" the startup fails.

additionally the partition holding all vservers is remounted readonly.

This does not happen, if already a vserver is running ...

Andreas <medic>

 

No files currently attached

 

Depends on the following items: None found

Items that depend on this one: None found

 

Carbon-Copy List
  • -unavailable- added by daniel_hozac (Posted a comment)
  • -unavailable- added by medic (Submitted the item)
  •  

    Do you think this task is very important?
    If so, you can click here to add your encouragement to it.
    This task has 0 encouragements so far.

    Only logged-in users can vote.

     

    Please enter the title of George Orwell's famous dystopian book (it's a date):

     

     

    Follow 3 latest changes.

    Date Changed By Updated Field Previous Value => Replaced By
    Fri 03 Apr 2009 04:42:01 PM UTCdaniel_hozacStatusNeed Info=>Ready For Test
      Assigned toNone=>daniel_hozac
    Thu 26 Mar 2009 06:02:35 PM UTCdaniel_hozacStatusNone=>Need Info

    Back to the top


    Powered by Savane 3.1-cleanup1