Currently, kernel config options whose value is "yes" always override
options whose value is "no".
This is not always desired.
Generally speaking, if someone defines an option to have the value
"no", presumably they are disabling the option for a reason, so it's
not always OK to silently enable it due to another, probably unrelated
reason.
For example, a user may want to reduce the kernel attack surface and
therefore may want to disable features that are being enabled in
common-config.nix.
In fact, common-config.nix was already silently enabling options that
were intended to be disabled in hardened/config.nix for security
reasons, such as INET_DIAG.
By eliminating the custom merge function, these config options will
now use the default module option merge functions which make sure
that all options with the highest priority have the same value.
A user that wishes to override an option defined in common-config.nix
can currently use mkForce or mkOverride to do so, e.g.:
BINFMT_MISC = mkForce (option no);
That said, this is not going to be necessary in the future, because
the plan is for kernel config options defined in nixpkgs to use a
lower priority by default, like it currently happens for other module
options.
the nix store may contain hardlinks: derivations may output them
directly, or users may be using store optimization which automatically
hardlinks identical files in the nix store.
The presence of these links are intended to be a 'transparent'
optimization. However, when creating a squashfs image, the image
will be different depending on whether hard links were present
on the filesystem, leading to reproducibility problems.
By passing '-no-hardlinks' to mksquashfs the files are stored
as duplicates in the squashfs image. Since squashfs has support
for duplicate files this does not lead to a larger image.
For more details see
https://github.com/NixOS/nixpkgs/issues/114331
- Actually use the zfsSupport option
- Add documentation URI to lxd.service
- Add lxd.socket to enable socket activatation
- Add proper dependencies and remove systemd-udev-settle from lxd.service
- Set up /var/lib/lxc/rootfs using systemd.tmpfiles
- Configure safe start and shutdown of lxd.service
- Configure restart on failures of lxd.service
- Use --netlink to avoid systemd-udev-settle[1]
- Run daemon in foreground which is preferred with systemd
- Add unit documentation
- Write ExecStart directly, no need for a script
[1]: 52bbd2b80b
The sysfs file /sys/kernel/mm/ksm/run seems to be available as soon as
the kernel has started, so no point in waiting for udev to "settle". If
for some reason it doesn't, we let the unit fail explicitly.
Launching a container with a private network requires creating a
dedicated networking interface for it; name of that interface is derived
from the container name itself - e.g. a container named `foo` gets
attached to an interface named `ve-foo`.
An interface name can span up to IFNAMSIZ characters, which means that a
container name must contain at most IFNAMSIZ - 3 - 1 = 11 characters;
it's a limit that we validate using a build-time assertion.
This limit has been upgraded with Linux 5.8, as it allows for an
interface to contain a so-called altname, which can be much longer,
while remaining treated as a first-class citizen.
Since altnames have been supported natively by systemd for a while now,
due diligence on our side ends with dropping the name-assertion on newer
kernels.
This commit closes#38509.
systemd/systemd#14467systemd/systemd#17220https://lwn.net/Articles/794289/
