qemu: 6.1.0 -> 6.2.0

[alyssais]

This is a draft because QEMU 6.2.0 isn't out yet — currently this PR is updating to a release candidate. I'm trying it this way because last time the QEMU update was delayed for weeks because of Darwin issues. I'm hoping that by opening the PR early, we can identify issues like that in advance, and then be ready to go when the final release comes out. QEMU 6.2.0 has now been released!

QEMU now supports automatically detecting which audio drivers to build, so we don't need to pass --audio-drv-list anymore.

pkgsMusl.qemu* doesn't build at the moment because of dependency issues, but with a lot of hacks I was able to do enough of a build to be confident the changes to patches etc. are correct for Musl.

TODO

• Upgrade Meson (meson: 0.57.1 -> 0.60.3, gst-plugins-base 1.18.4 -> 1.18.5 #144779)
• Revert the qemu64 change from qemu, runInLinuxVM: fix KVM availability check #125948 (if it's merged before this is ready), because QEMU 6.2.0 fixes Virtualized hosts failing to start guest VM after qemu update 6.0.0 -> 6.1.0 #141596.

Motivation for this change

Things done

• Built on platform(s)
  • x86_64-linux
  • aarch64-linux
  • x86_64-darwin
  • aarch64-darwin
• For non-Linux: Is sandbox = true set in nix.conf? (See Nix manual)
• Tested, as applicable:
  • NixOS test(s) (look inside nixos/tests)
  • and/or package tests
  • or, for functions and "core" functionality, tests in lib/tests or pkgs/test
  • made sure NixOS tests are linked to the relevant packages
• Tested compilation of all packages that depend on this change using nix-shell -p nixpkgs-review --run "nixpkgs-review rev HEAD". Note: all changes have to be committed, also see nixpkgs-review usage
• Tested basic functionality of all binary files (usually in ./result/bin/)
• 21.11 Release Notes (or backporting 21.05 Release notes)
  • (Package updates) Added a release notes entry if the change is major or breaking
  • (Module updates) Added a release notes entry if the change is significant
  • (Module addition) Added a release notes entry if adding a new NixOS module
• Fits CONTRIBUTING.md.

[alyssais]

@ofborg test simple cage cagebreak cloud-init os-prober sway virtualbox

(Apart from "simple", these are all the tests that use custom QEMU options, so probably give us a good spread of functionality.)

[Synthetica9]

I'm hoping that by opening the PR early, we can identify issues like that in advance, and then be ready to go when the final release comes out.

Good, we've done that for sway the last few releases and it worked really well to work out the kinks.

(maybe we should officially encourage this workflow somewhere?)

[alyssais]

We should have Meson ≥0.58.2 (with 0.59.2 recommended). Otherwise, QEMU will use its own internal Meson, which doesn't have our patches.

[alyssais]

#147210 will make it a build failure to use an incompatible Meson version with QEMU.

[Synthetica9]

#144779 targets staging while this targets master, shouldn't this also target staging if this is dependent on that?

[alyssais]

I think changing the base branch would be premature at this point. It's entirely possible #144779 will already be in staging-next or even master by the time this is ready to merge.

[zowoq]

Can we move forward with this by using pkgs.meson_0_60?

[Synthetica9]

Can we move forward with this by using pkgs.meson_0_60?

Resolved the merge conflict, rebased on master, and using meson_0_60. All NixOS tests I tried still worked, which is a good sign I think. Rebase available at https://github.com/Synthetica9/nixpkgs/commits/qemu-6.2.0

[alyssais]

I don't think meson_0_60 should have been added, and I'd rather wait for #144779 so fixing the mess of Meson versions we now have doesn't become even more complicated.

[alyssais]

The Meson issues should be resolved now, so once OfBorg is happy I'll undraft.

[alyssais]

Now that (x86_64) Darwin stdenv is unbroken:

@NixOS/darwin-maintainers call for Darwin testing, since I know QEMU is an important package, and Darwin caused such a big problem last QEMU upgrade, and OfBorg can't even build staging without timing out.

It looks like aarch64-darwin stdenv still doesn't work, but there's nothing I can do about that, and we can't hold upgrades forever because of platforms that are broken further up the dependency tree. If you want to test a platform with broken dependencies, you could try to cherry-pick the upgrade onto master (which I hope is working), but you'd also have to cherry-pick the Meson bump, which might be tricky because it ended up being split over multiple PRs.

[veprbl]

Works fine on x86_64-darwin when af89fb2 is applied to saging-next