Shutdown hangs on waiting for lvm when rc_parallel="YES"

gkmac

Some update in the past week has caused both my Gentoo boxes to fail to shutdown.

My root partition is within LVM on both boxes and for many many years up until now that has never been a problem, apart from a slight warning that "vggazanomi/gazanomirootssd contains a filesystem in use" but the shutdown always completed nethertheless.

Now it hangs around waiting for lvmetad to shutdown. I had to video the shutdown and transcribe what the screen says...

gkmac · Posted: Fri Dec 25, 2015 12:38 pm Post subject:

Judging by the deafening silence I seem to have the only two Gentoo boxes in the world that do this.

First I tried setting use_lvmetad = 0 in /etc/lvm/lvm.conf - no change. lvmetad still failed to stop.

Then I tried blocking lvmetad using this hint. This did trick things into not starting lvmetad, but sysfs still waited for lvm and caused the shutdown to hang. Again had to video the shutdown and type this all out...

morbid · Tux's lil' helper Joined: 05 Mar 2003 Posts: 90

I'm not sure why no one else has replied... but most of my systems are suddenly having this issue too. They're all doing parallel inits except my server, but I'm not rebooting that to test this. I have disabled parallel init on my laptop, and that does fix it... but I'd prefer to at least have my laptop have parallel enabled.

steveL · Posted: Wed Jan 06, 2016 6:20 pm Post subject:

Hmm this post might be useful if you want to check out what exactly is causing the "filesystem in use" error.

Really we should be looking at changes in the initscripts, but I don't have headspace for it atm; maybe in a week or two.

ISTR something about lvmetad being pulled in, but it's not needed for most setups. Or are we talking about setups where it is, indeed, needed?

fugue88 · n00b Joined: 30 Mar 2005 Posts: 13

I have this problem too, starting with an update I did yesterday. I had put off updating for about two months, but I can say that udev was updated and my kernel was not, at first. I don't remember if lvm was updated or rebuilt.

If I modify the lvm shutdown script to include -vvv -ddddd for verbose debugging output, the console will display that a udev lock/semaphore has a count of 2, which is where it hangs.

After getting the hang reproducibly, I updated my kernel from 4.0.5 to 4.1.15 and rebuilt udev, but that didn't help.

If I change from parallel rc to not, I don't get a hang. If I `init 1` first, then shutdown, I also won't get a hang even if rc is parallel.

My root filesystem is not on lvm, but /home is. /home unmounts successfully, and the LV and VG are disabled, before the hang happens.

fugue88 · n00b Joined: 30 Mar 2005 Posts: 13

If I downgrade from udev-225 to udev-216, I can reliably do a parallel shutdown without hanging.

wmatthews · Posted: Thu Mar 10, 2016 11:29 pm Post subject:

c00l.wave · Apprentice Joined: 24 Aug 2003 Posts: 264

Any new insights on this issue? I did an update last week (I've put it off for much too long) and I'm now facing the same issue. I don't seem to be able to downgrade due to gudev requiring a later version. Parallel boot worked fine for me ever since it was introduced, too bad it's broken now...

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nohup nice -n -20 cp /dev/urandom /dev/null &

BeerSerc · n00b Joined: 06 Oct 2016 Posts: 7

has this been solved? I have the same issue here...