Re: 100% CPU before LUKS password

[Andrei Borzenkov]

On 20.11.2022 13:23, Defiant wrote:
> I noticed this behavior too using my custom Xubuntu setup with GRUB
> folder located in the /boot folder inside the LUKS-encrypted ext4 rootfs
> partition. Grub was setup with GRUB_ENABLE_CRYPTODISK=y. The grub binary
> at /boot/efi/EFI/ubuntu/grubx64.efi seems to be causing my CPU fan to
> spin while waiting at the initial password prompt (before the rootfs is
> decrypted).

grub busy loops when checking for input characters which may explain this.

> On 11/20/22 04:17, Tim Lewis wrote:
> > While some Linux distributions (Debian, Fedora, etc) put /boot outside of LUKS,
> > the ones using the Calamares installer (EndeavourOS, Spiral, etc)
> > often put /boot inside LUKS/btrfs.
> > The latter layout permits kernel rolebacks via btrfs snapshots, but
> > will use 100% of one core until the kernel is loaded.
> > This is easy to reproduce and observe in KVM.
> >
> > Is Calamares missing a GRUB configuration or is this a bug?