[systemd-devel] fsck checking: concurrent device access problem

Thu Dec 1 10:04:50 PST 2011

On 08/16/2011 08:05 AM, Mariusz Bialonczyk wrote:
> On 08/02/2011 01:48 AM, Lennart Poettering wrote:
>> On Sat, 30.07.11 01:11, Mariusz Bialonczyk (manio at skyboo.net) wrote:
>>>
>>> Hello again
>>> I want to bring some new light on this issue. It seems that passno doesn't solve the
>>> "busy device" issue (I tested it on debian's systemd v25-2 and also 29-1).
>>> >From time to time I've got the following error when starting (maybe about 1/4 of all reboots):
>>> systemd-fsck[572]: fsck.ext4: Device or resource busy while trying to open /dev/md4
>>> systemd-fsck[572]: Filesystem mounted or opened exclusively by another program?
>>> But when I reboot another time the system boot up normally.
>>>
>>> Full screen from this boot process: http://skyboo.net/IMG_8188.JPG
>>> It seems that there is a problem with fsck-ing /dev/md devices (race condition?).
>>> Any news/tips to solve this? This is very annoying when the host is not always starting :(
>>
>> Hmm, I have not seen a similar problem. My guess is though that there's
>> some borkage with the RAID udev rules (are there any?): i.e. race
>> between systemd spawning fsck on the md devices and some other code
>> (that might be spawned from the udev rule) that does the same.
>>
>> Kay, do you have an idea?
>>
>> Lennart
>>
> Today I reproduced the problem with debugging turned on.
> The original screen photo is here: http://skyboo.net/systemd/IMG_8214.JPG
> But I retyped the essential info below:
> -------------------------------------- start here
> systemd-fsck[   11.908231] systemd-fsck[127]: /dev/md0: clean, 85842/458752 files, 937206/1834480 blocks
> [127]: /dev/md0: clean, 85842/458752 files, 937206/1834480 blocks
> Started File System Check on Root Device.
> done.
> Started LSB: Set preliminary keymap.
> Starting Remount Root FS...
> Starting File System Check on /dev/disk/by-uuid/33a13f77-6e5a-4c1e-b959-d891b0a77488...
> [   12.441172] EXT4-fs (md0): re-mounted. Opts: errors=remount-ro
> Started Remount Root FS.
> Starting LSB: Clean old interface status info during boot....
> Starting LSB: mount emergency /tmp....
> Cleaning up ifupdown...Starting /dev/disk/by-uuid/af8133a0-e9a5-4fcf-81e4-c87c2bb50ac8...
> Started LSB: mount emergency /tmp..
> .
> Started LSB: Clean old interface status info during boot..
> Starting LSB: Prepare the system for taking up interfaces....
> [   12.801958] Adding 1048508k swap on /dev/md3. Priority:0 extents:1 across:1048508k
> Started /dev/disk/by-uuid/af8133a0-e9a5-4fcf-81e4-c87c2bb50ac8.
> Setting up networking....
> Started LSB: Prepare the system for taking up interfaces..
> systemd-fsck[   13.569809] systemd-fsck[59]: /dev/md4: clean, 2734236/57581568 files, 203991321/230296816 blocks
> [596]: /dev/md4: clean, 2734236/57581568 files, 203991321/230296816 blocks
> Started File System Check on /dev/disk/by-uuid/33a13f77-6e5a-4c1e-b959-d891b0a77488.
> Starting File System Check on /dev/disk/by-uuid/33a13f77-6e5a-4c1e-b959-d891b0a77488...
> Starting /home...
> [   14.137995] mount[672]: mount: /dev/md4 already mounted or /home busy
> [   14.138399] systemd[1]: home.mount mount process exited, code=exited status=32
> Starting /home failed, see `systemctl status home.mount` for details.
> [   14.178352] systemd[1]: Job local-fs.target/start failed with result `dependency`.
> [   14.183514] systemd[1]: Triggering OnFailure= dependencies of local-fs target.
> [   14.184655] systemd[1]: Unit home.mount entered failed state.
> Cleaning up ifupdown....
> Welcome to emergency mode. Use "systemctl default" or ^D to activate default mode.
> Give root password for maintenance
> (or type Control-D to continue):
> -------------------------------------- end here
> Maybe now you know hot get rid of this problem...
> 
> regards,

bump

The problem is still here with debian's systemd version 37-1.
I have to admit that this problems is occurring much more rarer then
it was previously, but it sometimes still hapenning.
This is the screen photo from two days ago:
http://skyboo.net/systemd/IMG_8411.JPG

regards,
-- 
Mariusz Białończyk
jabber/e-mail: manio at skyboo.net
http://manio.skyboo.net