Nixpkgs: btrfs raid rootfs timing problem leads to mount fail

[petabyteboy]

Describe the bug
I see "btrfs device scan" in my stage 1 script. When I boot, it fails to mount the rootfs. When I drop into the initrd shell, run btrfs device scan and repeat the exact mount command that failed, it works.

To Reproduce
Steps to reproduce the behavior:

1. install a system with btrfs raid as root
2. have specific hardware I guess?
3. see it fail to boot

Expected behavior
File system should be mounted

Screenshots
https://img.pbb.lc/id/Nk95LNx7nWQT623A

Metadata

• system: "x86_64-linux"
  
  
  
  • host os: Linux 5.4.0, NixOS, 20.03.20191125.89b2c0b (Markhor)
  
  
  • multi-user?: yes
  
  
  • sandbox: yes
  
  
  • version: nix-env (Nix) 2.4pre20191022_9cac895
  
  
  • channels(root): "nixos-20.03pre202991.57cf4eb83bc"
  
  
  • nixpkgs: /nix/var/nix/profiles/per-user/root/channels/nixos
  
  

Maintainer information:

# a list of nixpkgs attributes affected by the problem
attribute:
# a list of nixos modules affected by the problem
module:
- boot.initrd

[ikervagyok]

See if this helps: https://github.com/NixOS/nixpkgs/issues/32588. There are a few people who had the same/similar problems with Btrfs over the last few years.

[petabyteboy]

Yes, I also knew about this workaround from IRC, but this obviously shouldn't happen in the first place. Probably there should be some loop doing "btrfs device scan" and trying to mount with a timeout.

[petabyteboy]

I guess this is kind of a duplicate but I would like to keep it open until there is a proper fix. I might prepare a PR for this.

[stale[bot]]

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[petabyteboy]

When did we add this annoying bot?
It's still an issue for me.