[Nix-dev] xen on nixos

[Jan Malakhovski]

Hi Marco,

On Fri, 7 Sep 2012 15:27:49 +0200
Marco Maggesi <maggesi at math.unifi.it> wrote:
> Following the usual instructions I get the following error:
> 
>    builder for `/nix/store/bmr08239ljmcbws3xm6wvsmgp3mz4a1n-linux-2.6.32.24-xen-179eca5'
> failed
That might be the case, I have not tried to run xen with 2.6.
 
> Then I added the following line to configuratio.nix
> 
>   boot.kernelPackages = pkgs.linuxPackages_3_2_xen;
This should work.
 
> but then I get another error:
> 
> Checking that all programs call by absolute paths in udev rules exist ... FAIL
> /etc/xen/scripts/blktap is called in udev rules but not installed by udev
> builder for `/nix/store/vbqrjkgha77ik3gwxghfx91bxnag3dqd-udev-rules.drv'
> failed with exit code 1
Yup. It's an error generated by nixos, not nixpkgs. I'm not sure if there is nice and easy solution.
Xen's udev rules have A LOT of dependencies and digging them out and replacing all of them with absolute paths by hand is pain.
I solved this with a dirty hack by commenting out "exit 1" commands at 70th and 84th lines in nixos/modules/services/hardware/udev.nix which magically transforms this error into a warning (kind of).
grep this file for "FAIL" and "not installed by udev" and see for yourself.
After that you might (or not) need to add some of this utils' "/bin"s to udev's PATH (e.g. blktap's) which is a dirty hack too.

Would be nice to have a lib helper to simplify this <command name> -> <absolute path> transform somehow.

Best regards,
  Jan