4c1ddb3a57
Our VM tests and everything related to our virtualisation infrastructure is currently broken if used with kernel 4.19 or later. The reason for this is that since 4.19, overlayfs uses the O_NOATIME flag when opening files in lowerdir and this doesn't play nice with the way we pass the Nix store to our QEMU guests. On a NixOS system, paths in the Nix store are typically owned by root but the QEMU process is usually run by an ordinary user. Using O_NOATIME on a file where you're not the owner (or superuser) will return with EPERM (Operation not permitted). This is exactly what happens in our VM tests, because we're using overlayfs in the guests to allow writes to the store. Another implication of this is that the default kernel version for NixOS 19.03 has been reverted to Linux 4.14. Work on getting this upstream is still ongoing and the patch I posted previously was incomplete, needs rework and also some more review from upstream maintainers - in summary: This will take a while. So instead of rushing in a kernel patch to nixpkgs, which will affect all users of overlayfs, not just NixOS VM tests, I opted to patch QEMU for now to ignore the O_NOATIME flag in 9p. I think this is also the least impacting change, because even if you care about whether access times are written or not, you get the same behaviour as with Linux 4.19 in conjunction with QEMU. Signed-off-by: aszlig <aszlig@nix.build> Fixes: https://github.com/NixOS/nixpkgs/issues/54509 |
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| .github | ||
| doc | ||
| lib | ||
| maintainers | ||
| nixos | ||
| pkgs | ||
| .editorconfig | ||
| .gitattributes | ||
| .gitignore | ||
| .version | ||
| COPYING | ||
| default.nix | ||
| README.md | ||
Nixpkgs is a collection of packages for the Nix package manager. It is periodically built and tested by the Hydra build daemon as so-called channels. To get channel information via git, add nixpkgs-channels as a remote:
% git remote add channels https://github.com/NixOS/nixpkgs-channels.git
For stability and maximum binary package support, it is recommended to maintain
custom changes on top of one of the channels, e.g. nixos-18.09 for the latest
release and nixos-unstable for the latest successful build of master:
% git remote update channels
% git rebase channels/nixos-18.09
For pull requests, please rebase onto nixpkgs master.
NixOS Linux distribution source code is located inside
nixos/ folder.
- NixOS installation instructions
- Documentation (Nix Expression Language chapter)
- Manual (How to write packages for Nix)
- Manual (NixOS)
- Community maintained wiki
- Continuous package builds for unstable/master
- Continuous package builds for 18.09 release
- Tests for unstable/master
- Tests for 18.09 release
Communication:
Note: MIT license does not apply to the packages built by Nixpkgs, merely to the package descriptions (Nix expressions, build scripts, and so on). It also might not apply to patches included in Nixpkgs, which may be derivative works of the packages to which they apply. The aforementioned artifacts are all covered by the licenses of the respective packages.