Re: [libvirt] [PATCH v4 00/23] Introduce metadata locking

Michal Privoznik <mprivozn(a)redhat.com&gt; [2018-09-10, 11:36AM +0200]: > Technically, this is v4 of: > > https://www.redhat.com/archives/libvir-list/2018-August/msg01627.html > > However, this is implementing different approach than any of the > previous versions. > > One of the problems with previous version was that it was too > complicated. The main reason for that was that we could not close the > connection whilst there was a file locked. So we had to invent a > mechanism that would prevent that (on the client side). > > These patches implement different approach. They rely on secdriver's > transactions which bring all the paths we want to label into one place > so that they can be relabelled within different namespace. > I'm extending this idea so that transactions run all the time > (regardless of domain namespacing) and only at the very last moment is > decided which namespace would the relabeling run in. > > Metadata locking is then as easy as putting lock/unlock calls around one > function. > > You can find the patches at my github too: > > https://github.com/zippy2/libvirt/tree/disk_metadata_lock_v4_alt Hey Michal, is was running a quick test with this patch series with two domains sharing a disk image without <shareable/> and SELinux enabled. When starting the second domain, the whole libvirtd daemon hangs for almost a minute until giving the error that the image is locked. I haven't debugged it yet to figure out what happens.