[Nix-dev] [Nix-commits] SVN commit: nix - r33428 - in nixpkgs/branches/kmod-MODULE_DIR/pkgs: applications/virtualization/virtualbox applications/virtualization/virtualbox/guest-additions build-support/kernel os-specific/l...

[Yury G. Kudryashov]

Shea Levy wrote:

> On 03/26/2012 11:28 AM, Yury G. Kudryashov wrote:
>> Shea Levy wrote:
>>
>>> On 03/26/2012 11:15 AM, Yury G. Kudryashov wrote:
>>>> We'll maintain /lib/modules/modversion symlink instead. This way both
>>>> module-init-tools and libkmod will work without patches.
>>> I really don't like this approach. Given that the kmod tools accept a
>>> --dirname=DIR option that allows you to point to the modules directory,
>>> why add this additional impurity?
>> This way we're closer to what upstream supports.
> 
> Upstream supports --dirname=DIR for modprobe. We don't even need a patch
> for this.
> 
>>
>> Why do you consider this to be an impurity? You can't have two kernels
>> running at the same time anyway. And if you want to load a module from
>> another directory, use `-d` or `insmod`.
> 
> Because a package might search /lib/modules during install for some
> reason. Many kernelPackages do so (and need to be patched to fix this),
> and if there were a /lib/modules symlink then you'd have problems
> building a kernelPackage for a kernel that's not the currently running
> one.
There is no /lib/modules symlink. There are /lib/modules/modDirVersion 
symlinks. And these symlinks are invisible in build chroot. If you build 
without chroot, you'll have problems on non-NixOS systems anyway.

> 
>> Eelco Dolstra wrote:
>>> I dislike introducing a /lib/modules.  What was wrong with using an
>>> environment variable to point at the modules tree?
>> E.g., next udev version relies on libkmod (not `modprobe`) to load
>> modules. This way we can switch a symlink on nixos-rebuild switch. Any
>> ideas how to do it with env var?
> 
> Patch udev to call kmod_new with the appropriate directory, or patch
> libkmod to respect the env var.
How do you want to *change* udev's env var on the fly when you do nixos-
rebuild switch?
-- 
Yury G. Kudryashov,
mailto: urkud at mccme.ru