pkg update of base system pkg enters infinite loop if upgrade target file is mountpoint

[dch]

background

In OCI containers, the podman tool mounts a per-network /etc/hosts file into the jail, to provide name resolution between containers. pkg does not like this, and is unable to handle the failure.

issue

During pkg update -r FreeBSD-base the FreeBSD-runtime package includes /etc/hosts as well.

The update will appear to hang, consuming 100% CPU core indefinitely.

procstat was unhelpful but ktrace shows this happening continuously:

 99531 pkg      NAMI  "etc/.[pkgtemp.hosts](http://pkgtemp.hosts/).n1H6tDhSrrjZ"
 99531 pkg      NAMI  "etc/hosts"
 99531 pkg      NAMI  "etc/.[pkgtemp.hosts](http://pkgtemp.hosts/).n1H6tDhSrrjZ"
 99531 pkg      NAMI  "etc/hosts"
 99531 pkg      NAMI  "etc/.[pkgtemp.hosts](http://pkgtemp.hosts/).n1H6tDhSrrjZ"
 99531 pkg      NAMI  "etc/hosts"
...

workaround

For oci containers, add --no-hosts during your podman build or buildah invocation and the /etc/hosts file will not be mounted, avoiding the loop.