Since udev will probe block devices it is advisable to hold a lock
on the device when modifying its partition table or the superblock
of the filesystem (see [1]). osbuild loopback devices do support
this via the `lock` option. Set this option for all operation that
involve changing block device "metadata" that could potentionally
race with udev, such as sfdisk, mkfs, creating a luks2 container
and creating LVM2 volume groups and logical volumes.
NB: osbuild also has its own device inhibition logic to prevent
udev/lvm2 from auto activating devices and in general to limit the
interaction between the host and devices used by osbuild. See [2]
for more information.
NB: this also locks the loopback device in situation where we the
it is strickly not the right thing to do, e.g. when creating a fs
on a logical voume that is located on a loopback device, since in
this case the device we would need to lock is the logical volume.
Sadly, LVM/DM devices are exempt from block device locking. But,
due to a bug in osbuild < 50, the udev inhibitor does *not* work
for loopback devices and therefore we have to use the actual lock
to preven LVM device auto-activation via `69-dm-lvm-metad.rules`.
The change was implemented by adding a new boolean to `getDevices`
indicating if the loopback device should be locked or not. Once
we depend on osbuild 50 we can change the logic in `getDevices`
to only lock the loopback device if the number of devices is one,
i.e. we are working directly on the loopback device.
[1] https://systemd.io/BLOCK_DEVICE_LOCKING/
[2] /usr/lib/udev/rules.d/10-osbuild-inhibitor.rules
We want to support LVM on all image types (optionally) so let's make
lvm2 available in all build roots.
Manifests and image info updated for RHEL 8.6 and CentOS Stream 8.
Signed-off-by: Achilleas Koutsou <achilleas@koutsou.net>
Use entity based method `ForEachMountable` and `getDevices` to generate
all mounts and devices in a generic way, which then allows for mounts on
arbitrarily nested devices.
Update manifests and image info:
- New device names generated by `pathdot()` to avoid basename
collisions.
- Some partitions are generated in a different order now which changes
the order they appear in the manifest and their UUIDs.
Co-Authored-By: Christian Kellner <christian@kellner.me>
Instead of hard coding a padding of 100 sectors for all layouts, i.e.
MBR and GTP, adjust the needed space depending on the layout: for MBR
we don't need to reserve any space at all since it does not have a
secondary header. For GTP we reserve 33 sectors, as indicated in the
UEFI specific, which allows for the header itself and up to 128 entries.
To not modify the layout of already released distributions, like RHEL
8.4 and 8.5, a new member called `ExtraPadding` is added to `Partition
Table` and then used in the corresponding layouts to preserve the
existing padding of 100.
RHSM configuration is now applied conditionally only on RHEL. The same
applies to the customization to subscribe the system on first boot.
The reason is that the CentOS `@core` package group does not contain
`subscription-manager`. Thus it is not installed on CentOS Stream by
default and also CentOS 8 image definitions don't apply any changes
to the RHSM configuration [1].
In addition, make sure to not install any subscription-manager
packages on CentOS Stream images.
Regenerate all CentOS 8 image test cases.
[1] https://git.centos.org/centos/kickstarts/tree/master
Signed-off-by: Tomas Hozza <thozza@redhat.com>
