Thanks to everyone who responded!

As Lennart points out, /boot can't be an LVM, and the whole rest of the disk was an LVM partition.  Those get bigger easily, but not smaller.

It was easiest for me to copy my /home onto a backup drive and reinstall Debian.  My experiment with LVM and "automatic" partitions was a failure - my workflow is better suited to a / and a /home.

Thanks again!

On Tue., Oct. 12, 2021, 10:57 Lennart Sorensen, <lsorense@csclub.uwaterloo.ca> wrote:
On Thu, Oct 07, 2021 at 10:45:57PM -0400, William Witteman via talk wrote:
> When I installed Debian on my current computer, I (foolishly) let the
> install script partition my disk.  Now I have a /boot partition that is too
> small.
>
> The system is using lvm, and I have enough free space on /home that I can
> reduce the size of /home by a couple of Gb, and then in theory allocate
> that to my ridiculously undersized /boot partition.
>
> Back in the old days I knew how to do this, but with lvm I don't know how,
> and of the (many) questions and answers that I have found I haven't seen
> one that inspires confidence.
>
> So...
>
> 1) Do I need to make a boot drive?
> 2) Does anyone know a nice set of instructions?

Well you may in fact need a boot drive since you are using LVM for / and
something has to boot the system to a ramdisk to start lvm to mount root.

gparted livecd can definitely expand LVM PV, but not sure about shrinking
them.

What is the current partition table?

--
Len Sorensen