[linux-lvm] autoactivation fails

[Christian Hesse]

Christian Hesse <list at eworm.de> on Thu, 2015/05/21 20:57:
> Ondrej Kozina <okozina at redhat.com> on Thu, 2015/05/21 17:09:
> > Hi Christian,
> > 
> > On 05/21/2015 02:19 PM, Christian Hesse wrote:
> > > Hello everybody,
> > >
> > > with recent lvm2 I had problems booting an Arch Linux system with
> > > non-systemd initramfs. lvmetad is launched, but volumes are not
> > > activated. A git bisect reported this bad commit:
> > > commit fe30658a4d5fe4e4e6bb346c9c9ee7142a98f49d
> > > Author: Ondrej Kozina <okozina at redhat.com>
> > 
> > I would like to ask you for more information about the issue. First, 
> > have you managed to collect any error messages during the init phase 
> > where it's supposed to fail?
> > 
> > The thing about that particular commit is it could possibly break 
> > background polling, but I don't see (yet) how it could have damaged the 
> > activation code. Have you tried to reboot a system where any operation 
> > like: pvmove, lvconvert --merge or lvconvert mirror conversion was in 
> > progress in background before you rebooted the system by any chance?
> 
> No. And I see this on different systems. It's perfectly reproducable.
> 
> > Second step would be to unmute the eventual background processes spawned 
> > during activation. To do it just uncomment
> > 
> > // #define DEBUG_CHILD
> > 
> > in tools/toollib.c:76 lvm2 sources and rebuild.
> > 
> > This should expose all error messages from within the forked off 
> > processes.
> 
> Defining DEBUG_CHILD does not bring any changes... Not sure where output
> goes if there is any.
> 
> However it looks like the issue is not in lvmetad itself but triggers one
> in lvm. lvmetad is running with pid 69, but I see a log entry about
> segmentation fault of pid 121:
> 
> lvm[121]: segfault at 58 ip 00007f2f24197d20 sp 00007ffe3b499b18 error 4 in
> libc.so.6[7f2f24161000+1990000]
> 
> Not sure what command lvm is running, though. Probably pvscan, no?
> 
> BTW, if I run 'vgchange -ay' (well, actually 'lvm vgchange -ay' as it is a
> multicall binary) in rescue shell the volumes are activated and boot
> continues.
> 
> > Also, if you could perhaps give me some hints how to get the 
> > Arch Linux in the same state as when you experienced the issue it would 
> > help us as well.
> 
> I could upload a disk image that demonstrates the issue... Any preferences
> about the format?

Ok, here we go...

http://www.eworm.de/tmp/lvm2.vdi.gz

This is is Virtualbox disk image, compressed with bzip2.

It just contains boot loader, kernel and initramfs, but it demonstrates the
issue. Have fun! ;)
-- 
main(a){char*c=/*    Schoene Gruesse                         */"B?IJj;MEH"
"CX:;",b;for(a/*    Chris           get my mail address:    */=0;b=c[a++];)
putchar(b-1/(/*               gcc -o sig sig.c && ./sig    */b/42*2-3)*42);}
-------------- next part --------------
A non-text attachment was scrubbed...
Name: not available
Type: application/pgp-signature
Size: 473 bytes
Desc: OpenPGP digital signature
URL: <http://listman.redhat.com/archives/linux-lvm/attachments/20150521/f765f169/attachment.sig>