Comment # 3 on bug 997575 from Filipe Manana

(In reply to Oliver Kurz from comment #0)
> Created attachment 691135 [details]
> y2log after filesystem turned read-only
> 
> ## observation
> Calling zypper install and remove of a package in a loop for many times
> fails at some time with an error message that the media point is bad or
> something. It turns out the btrfs filesystem was turned read-only.
> Testing on a physical notebook machine.
> 
> ## steps to reproduce
> 
> * On a Tumbleweed 20160901 installation with btrfs filesystem call
> * `for i in {1..1000000} ; do echo $i ; zypper -n in nfs-kernel-server ;
> zypper -n rm nfs-kernel-server ; done`
> * see it fail after some time
> 
> 
> ## problem
> 
> Might be related to bug #990384 and I also intended to do a proper
> crosscheck after I had some similar symptoms yesterday with only qemu-x86_64
> machines.
> I will try to reproduce again after a reboot (or reinstall).
> 
> Logs attached, please take a look.

Yes it's the same as #990384.
The same debugging instructions listed there are needed.
This depends on specific timings and at least snapshoting is happening in
parallel (or has happened before that loop at least). The same has happened and
reported rarely upstream (an extent item is missing in the extent tree for some
unknown reason).