Comment 78 for bug 1423672

I'd like to follow up because the issue seems to have cleared up for us after installing linux 5.0.1 about 40 days ago. It's hard to say whether everyone is experiencing the same bugs, but give 5.x a shot and let us know how it goes!

Just to recap. Every week or so we were seeing R/O file systems with the follow errors, which required reboot & fsck.

EXT4-fs error (device vda2): ext4_mb_generate_buddy:757: group 144, block bitmap and bg descriptor inconsistent: 23914 vs 23913 free clusters
Aborting journal on device vda2-8.
EXT4-fs (vda2): Remounting filesystem read-only

We never experienced any corruption on the host itself, only under KVM guests.

Host DELL Poweredge 2950III
Several KVM Guests: linux OS, distro&kernel doesn't make any difference, all randomly vulnerable during periods of high disk activity.

Not sure it matters, but in our case we were using LVM2 volumes on the host and kvm media was configured as follows "media=disk,if=virtio,cache=none,aio=native,format=raw".

We initially thought just one guest was affected, but over time we saw it happen with many distros and kernels. It wasn't until we had an extended period of downtime that we decided to reinstall the host with a 5.x kernel. None of the guests experienced any issues since, fingers crossed.

At this point, it's hard to recommend Ubuntu 19.04 given that it's only a few months away from EOL, however the 5.x kernel seems promising whereas the Ubuntu 18.04LTS runs an older kernel that is still known to exhibit the corruption. For LTS I'd look into running it under a custom setup with a newer kernel.