As per the in-line comment, this is where distros should configure it.
Not via kernel command line parameters.
As found by looking at the implementation, while exploring the cause of
a bug on the Raspberry Pi 4, it was found that `cma=` on the command
line parameters will overwrite the values a device tree will have
configured for a given platform.
With this, the more recent 5.4 vendor kernel boots just fine on the
Raspberry Pi 4 using our common configuration.
This includes setting up everything for the mainline Raspberry Pi 4
image.
In fact, the only difference left in the Raspberry Pi 4-specific image
is the kernel from the vendor.
Prior to this commit, installation over serial console would requiring
manually having to modify the kernel modeline, as described in
https://github.com/NixOS/nixpkgs/issues/58198 .
This is unnecessarily fiddly, so this commit adds a syslinux boot
entry that has serial enabled.
GRUB already has a serial console entry:
2c07a0800a/nixos/modules/installer/cd-dvd/iso-image.nix (L311-L317)
Why 115200 bps? This is already used in other places, e.g. https://github.com/NixOS/nixpkgs/pull/58196
I tested this change by building the image, booting the image, and
observing the boot process over serial:
$ cd nixos/
$ nix-build -A config.system.build.isoImage -I nixos-config=modules/installer/cd-dvd/installation-cd-minimal.nix default.nix
$ sudo cp /nix/store/arcl702c3z8xlndlvnfplq9yhixjvs9k-nixos-20.09pre-git-x86_64-linux.iso/iso/nixos-20.09pre-git-x86_64-linux.iso /dev/sdb
$ picocom -b 115200 /dev/ttyUSB0
This reverts commit aab534b894 & uses the
driverInteractive attribute for the test driver instead.
This has the same effect but removes the extra module in the
nixos-build-vms code.
When I test a change e.g. in the module system manually, I usually use
`nixos-build-vms(8)` which also gives me a QEMU window where I can play
around in the freshly built VM.
It seems as this has changed recently when the default package for
non-interactive VM tests using the same framework was switched to
`pkgs.qemu_test` to reduce the closure size. While this is a reasonable
decision for our CI tests, I think that you really want a QEMU window of
the VM by default when using `nixos-build-vms(8)`.
[1] bc2188b083
The only nix version available in the installer should be the version
configure in the module system. If someone needs `nixUnstable` in their
`nixos-install` they should probably set the module option and not just
add it to the closure.
$EDITOR is allowed to contain flags, so it is important to allow the
shell to split this normally. For example, Sublime Text needs to be
passed --wait, since otherwise it will daemonise.
$NIXOS_CONFIG can be set to a directory, in which case the file used
is $NIXOS_CONFIG/default.nix. This updates 'nixos-rebuild edit' to
handle that case correctly.
This allows to perform `dd if= of=$img` after the image is built
which is handy to add e.g. uBoot SPL to the built image.
Instructions for some ARM boards sometimes contain this step
that needs to be performed manually, with this patch it can be
part of the nix file used to built the image.
The nix store more-or-less requires o+rx on all parent directories.
This is primarily because nix runs builders in a uid/gid mapped
user-namespace, and those builders have to be able to operate on the nix
store.
This check is especially helpful because nix does not produce a helpful
error on its own (rather, creating directories and such works, it's not
until 'mount --bind' that it gets an EACCES).
Helps users who run into this opaque error, such as in #67465.
Possibly fixes that issue if bad permissions were the only cause.
This should have been done initially, as otherwise it gets awfully
awkward to boot into new generations by default.
This system-specific image wasn't expected to be long-lived, thus why it
didn't end up being polished much.
Reality shows us we may be stuck with it for a bit longer, so let's make
it easier to use for new users.
'nix build' is an experimental command so we shouldn't use it
yet. (nixos-rebuild also uses 'nix', but only when using flakes, which
are themselves an experimental feature.)
nix build should store it's temporary files on target filesystem.
This should fix 'No space left on device' on systems
with low amount of RAM when there is a need to build something
like Linux kernel
For imports, it is better to use ‘modulesPath’ than rely on <nixpkgs>
being correctly set. Some users may not have <nixpkgs> set correctly.
In addition, when ‘pure-eval=true’, <nixpkgs> is unset.
When trying to build a VM using `nixos-build-vms` with a configuration
that doesn't evaluate, an error "at `<unknown-file>`" is usually shown.
This happens since the `build-vms.nix` creates a VM-network of
NixOS-configurations that are attr-sets or functions and don't contain
any file information. This patch manually adds the `_file`-attribute to
tell the module-system which file contained broken configuration:
```
$ cat vm.nix
{ vm.invalid-option = 1; }
$ nixos-build-vms vm.nix
error: The option `invalid-option' defined in `/home/ma27/Projects/nixpkgs/vm.nix@node-vm' does not exist.
(use '--show-trace' to show detailed location information)
```
we use stdenv.hostPlatform.uname.processor, which I believe is just like
`uname -p`.
Example values:
```
(import <nixpkgs> { system = "x86_64-linux"; }).stdenv.hostPlatform.uname.processor
"x86_64"
(import <nixpkgs> { system = "aarch64-linux"; }).stdenv.hostPlatform.uname.processor
aarch64
(import <nixpkgs> { system = "armv7l-linux"; }).stdenv.hostPlatform.uname.processor
"armv7l"
```
Instead of making the configuration less portable by hard coding the number of
jobs equal to the cores we can also let nix set the same number at runtime.
The volumeID will now be in the format of:
nixos-$EDITON-$RELEASE-$ARCH
an example for the minimal image would look like:
nixos-minimal-20.09-x86-64-linux
Note we're not using wayland default in the graphical media because it
could cause headaches for Nvidia users. But the session is still available
if someone logs out.
In 0945178b3c we decided that Perl-based
VM tests should be deprecated and will be removed between 20.03 and
20.09. So let's switch `nixos-build-vms(8)` to python as well (which is
entirely interactive, so other scripts won't break).
In my experience, the test-driver isn't used most of the time, so this
patch is mainly supposed to get rid of the (probably misleading)
deprecation warning when running `nixos-build-vms`. Apart from that, the
interface for python's test-driver is way nicer.
In some cases, /dev/stderr may not point to a sensible location. For
example, running nixos-enter inside a systemd unit where the unit's
StandardOutput and StandardError are set to be sockets. In these
cases, this line would fail.
Piping to fd2 directly works just as well, even under strange and
twisted executions.
Co-authored-by: Michael Bishop <michael.bishop@iohk.io>
