[Libguestfs] Re: Race condition in VM setup?

Running libguestfs-related tools as part of tests (libguestfs itself, guestfs-tools, nbdkit, etc.) in Debian's build and autopkgtest infrastructure would lead to flaky tests which I had trouble reproducing. Examples of bug reports relating to this problem: - https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1121473 - https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1123409 - https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=1120924 Adding a partition and then creating or mounting a filesystem failed pretty often. I suspected a race condition involving udev creating the device node and I think it is more likely if qemu runs in TCG mode.