On Tue, 1 Dec 2020 03:23:11 +0100
Arnt Karlsen <arnt@???> wrote:

> On Mon, 30 Nov 2020 11:39:37 +0000, Le wrote in message
> <20201130113937.6da5d2fa@cruncher>:
>
> > Hello,
> >
> > I'm getting a circular problem upgrading cups in ceres. I've been
> > tackling this for a week or so. I need two root terminals open:
> > one to apt-get and the other to top + kill apt-get and dpkg.
>
> ..snip PITA details
>
Given up trying to find an answer. Not due to apparmor.

Workaround from
https://askubuntu.com/questions/1069702/dpkg-error-processing-package-install-info

#mv /var/lib/dpkg/info/install-info.postinst /var/lib/dpkg/info/install-info.postinst.bad
#mv /var/lib/dpkg/info/install-info.postrm /var/lib/dpkg/info/install-info.postrm.bad
#mv /var/lib/dpkg/info/install-info.prerm /var/lib/dpkg/info/install-info.prerm.bad
#dpkg -r printer-driver-cups-pdf

seems to restore apt-get functionality.

Posting for the record.

Best

fraser