overlayfs: allow with shiftfs as underlay
| Affects | Status | Importance | Assigned to | Milestone | |
|---|---|---|---|---|---|
| linux (Ubuntu) |
Fix Released
|
Undecided
|
Christian Brauner | ||
| Disco |
Fix Released
|
Undecided
|
Christian Brauner | ||
| Eoan |
Fix Released
|
Undecided
|
Christian Brauner | ||
Bug Description
SRU Justification
Impact: Currently it is not possible to use overlayfs on top of shiftfs. This means Docker inside of LXD cannot make user of the overlay2 graph driver which is blocking users such as Travis from making use of it efficiently.
Regression Potential: Limited to shiftfs and overlayfs on top of shiftfs. Overlayfs does prevent "remote" filesystems such as ceph, nfs, etc. from being used as the underlay. With this patch shiftfs however can be used as an underlay and we special case it as a suitable filesystem to be used under overlayfs. I verified that the patch does not lead to regression on overlayfs workloads that do not make use of shiftfs as underlay. Additionally, I tested Docker with the overlay2 graphdriver on top of shiftfs. This also has not lead to any regressions.
Test case: Building a kernel with the patch:
sudo snap install lxd
sudo lxd init
sudo lxc launch images:
sudo lxc config set b1 security.nesting true
sudo lxc restart --force b1
sudo lxc shell b1
sudo apt-get install \
apt-
ca-certificates \
curl \
gnupg-agent \
software-
curl -fsSL https:/
curl -fsSL get.docker.com | CHANNEL=test sh
sudo add-apt-repository \
"deb [arch=amd64] https:/
$(lsb_release -cs) \
stable"
sudo apt-get update
sudo apt-get install docker-ce docker-ce-cli containerd.io
sudo systemctl stop docker
cat <<EOF /etc/docker/
{
"storage-driver": "overlay2"
}
EOF
sudo systemctl start docker
docker run -it ubuntu bash
and observe that it works.
The old approach we used in https:/
Target kernels: All LTS kernels that do support shiftfs, if possible.
| Changed in linux (Ubuntu): | |
| assignee: | nobody → Christian Brauner (cbrauner) |
| status: | New → In Progress |
| Changed in linux (Ubuntu Disco): | |
| status: | New → In Progress |
| assignee: | nobody → Christian Brauner (cbrauner) |
| Changed in linux (Ubuntu Disco): | |
| status: | In Progress → Fix Committed |
| Changed in linux (Ubuntu Eoan): | |
| status: | In Progress → Fix Committed |
| Ubuntu Kernel Bot (ubuntu-kernel-bot) wrote | #1 |
| tags: | added: verification-needed-disco |
| tags: |
added: verification-done-disco removed: verification-needed-disco |
| Ubuntu Kernel Bot (ubuntu-kernel-bot) wrote | #2 |
| tags: | added: verification-needed-eoan |
| tags: |
added: verification-done-eoan removed: verification-needed-eoan |
| Ubuntu SRU Bot (ubuntu-sru-bot) wrote Autopkgtest regression report (linux-gcp-5.3/5.3.0-1008.9~18.04.1) | #3 |
| Launchpad Janitor (janitor) wrote | #4 |
| Changed in linux (Ubuntu Eoan): | |
| status: | Fix Committed → Fix Released |
| Launchpad Janitor (janitor) wrote | #5 |
| Changed in linux (Ubuntu Disco): | |
| status: | Fix Committed → Fix Released |
| Launchpad Janitor (janitor) wrote | #6 |
| Changed in linux (Ubuntu): | |
| status: | Fix Committed → Fix Released |
This bug is awaiting verification that the kernel in -proposed solves the problem. Please test the kernel and update this bug with the results. If the problem is solved, change the tag 'verification-
If verification is not done by 5 working days from today, this fix will be dropped from the source code, and this bug will be closed.
See https:/