Failed to add disk to instance 'charmcraft-mysql-router-834497-1-0-amd64'

[carlcsaposs-canonical]

Bug Description

2023-11-13 10:24:54.580 Failed to add disk to instance 'charmcraft-mysql-router-834497-1-0-amd64'.
2023-11-13 10:24:54.580 Detailed information: * Command that failed: 'lxc --project charmcraft config device add local:charmcraft-mysql-router-834497-1-0-amd64 disk-/root/.cache/pip disk source=/home/ubuntu/snap/charmcraft/common/cache/charmcraft/charmcraft-buildd-base-v2.0/BuilddBaseAlias.JAMMY/pip path=/root/.cache/pip'
* Command exit code: 1
* Command standard error output: b'Error: The device already exists\n'

To Reproduce

Unable to reproduce; likely caused by manually messing around with the environment (e.g. manually mounting the cache folder, swapping between charmcraft versions)

Environment

Ubuntu 22.04
charmcraft 2.5.0 snap rev 1736

charmcraft.yaml

# Copyright 2022 Canonical Ltd.
# See LICENSE file for licensing details.

type: charm
bases:
  # Whenever "bases" is changed:
  # - Update tests/integration/conftest.py::pytest_configure()
  # - Update .github/workflow/ci.yaml integration-test matrix
  - build-on:
      - name: "ubuntu"
        channel: "20.04"
    run-on:
      - name: "ubuntu"
        channel: "20.04"
  - build-on:
      - name: "ubuntu"
        channel: "22.04"
    run-on:
      - name: "ubuntu"
        channel: "22.04"
parts:
  charm:
    override-pull: |
      craftctl default
      if [[ ! -f requirements.txt ]]
      then
          echo 'ERROR: Use "tox run -e build" instead of calling "charmcraft pack" directly' >&2
          exit 1
      fi
    charm-entrypoint: src/machine_charm.py

Relevant log output

charmcraft-20231113-102334.961894.log

[carlcsaposs-canonical]

Note: only happens on 2nd base, not first base

[lengau]

Thanks for this report! I think this is something that is fixed by not mounting cache directories in base instances, which means it shouldn't occur again with 2.5.3 once we get that released. Please reopen if it does reoccur though.

cc @mr-cal for awarness