Control: retitle -1 grub-pc: use persistent disk identifier stored in configuration file Control: affects -1 - release.debian.org
[ Cc'ed -release@ to notify them it's not a regression after all ] On Wed, 05 Oct 2022 10:27:29 +0200 Ansgar wrote: > On Wed, 2022-10-05 at 09:48 +0200, Ansgar wrote: > > the upgrade to grub-pc 2.06-3~deb11u2 fails: > > > > +--- > > > Setting up grub-pc (2.06-3~deb11u2) ... > > > Installing for i386-pc platform. > > > grub-install: warning: this GPT partition label contains no BIOS > > > Boot Partition; embedding won't be possible. > > > grub-install: error: embedding is not possible, but this is > > > required for cross-disk install. > > > You must correct your GRUB install devices before proceeding: > > > > > > DEBIAN_FRONTEND=dialog dpkg --configure grub-pc > > > dpkg --configure -a > > > dpkg: error processing package grub-pc (--configure): > > > installed grub-pc package post-installation script subprocess > > > returned error exit status 1 > > > Errors were encountered while processing: > > > grub-pc > > > Log ended: 2022-09-23 06:09:42 > > +--- > [...] > > /dev/sda uses GPT and has one partition /dev/sda1; it was created > > this way by d-i (though it has the setting to use gpt enabled). > > Ah, but this was a distraction: /dev/sda isn't the boot device. The > boot device is currently /dev/sdb. That still has a DOS disk label; the > systems using GPT for the boot device as well have a small 1M partition > for BIOS boot. > > So grub-install shouldn't try to install to /dev/sda, but I find > nothing in /etc referencing /dev/sda at all (except for a comment in > /etc/fstab). So I'm not sure why the system tries to install grub > there. > > I now also checked /var/log/installer/syslog and when installing the > system /dev/sda and /dev/sdb were the other way around. And it looks > like that was the case before the previous reboot as well. > > So possibly one of the race conditions I read about? (FWIW, this is a > VM running under VMware.) >From some more investigation and chat on IRC: - Currently the only place where the configuration where grub should be installed is debconf, in particular grub-pc/install_devices. This should be moved to a configuration file in /etc. - grub should use a persistent device identifier instead of /dev/sda and similar. Steve McIntyre said on #-devel: | so we go to all the effort finding out the device details in a | sustainable way, then don't store it :facepalm: | we should be using a persistent device identifier here | and each time we run grub-install that should be re-resolved to a | /dev/*** reference | for added cleverness, we should also warn users that disks have moved | if we no longer find the disk(s) we expect to install ointo | and prompt for an update | so we pick up on disk replacement, etc. I think one has to check that grub doesn't get confused as well: in my case the device can be /dev/sda or /dev/sdb for Linux, but it should always be (hd0) for grub. Implementing this probably also requires changes to the grub-installer package. Ansgar
