[Bug 1889509] Re: grub boot error : "symbol 'grub_calloc' not found

[Jeff Turner]

Has anyone on an EFI system experienced this bug? I'm only seeing BIOS-
based systems affected.

My servers were AWS EC2 instances where the 'grub rescue>' state is only
a screenshot. To recover you need to reattach the broken volume to a
rescue instance and 'grub-install' to the volume there. Write-up of the
AWS process at:

https://www.redradishtech.com/display/~jturner/2020/07/30/symbol+%27grub_calloc%27+not+found+--+how+to+fix+on+AWS

Once recovered, I checked what my debconf settings were for grub.
Debconf had grub installing to one partition:

grub-pc       grub-pc/install_devices_disks_changed   multiselect
/dev/disk/by-id/nvme-
Amazon_Elastic_Block_Store_vol01678967bebb56f55-part1

However I know from trying manually that this would have failed with:

grub-install: warning: File system `ext2` doesn't support embedding.
grub-install: warning: Embedding is not possible.  GRUB can only be installed in this setup by using blocklists.  However, blocklists are UNRELIABLE and their use is discouraged..
grub-install: error: will not proceed with blockists.

I'm guessing I just didn't spot the error during the upgrade, and so was
left with an unbootable server.

Another observation: grub-pc is a rarely upgraded package. Prior to
today's update for BootHole, my dpkg.log suggests the last update was
July 2019. So perhaps we're all discovering problems that were latent in
the Debian/Ubuntu grub update process, and the problem is not BootHole-
specific?

-- 
You received this bug notification because you are a member of Ubuntu
Foundations Bugs, which is subscribed to grub2 in Ubuntu.
https://bugs.launchpad.net/bugs/1889509

Title:
  grub boot error : "symbol 'grub_calloc' not found

Status in grub2 package in Ubuntu:
  Confirmed
Status in grub2 package in Debian:
  New

Bug description:
  After updating grub2 (to 2.02~beta2-36ubuntu3.26) and rebooting, my
  server does not boot:

  Booting from Hard Disk 0...
  error: symbol `grub_callow' not found.
  Entering rescue mode...
  grub rescue> _

  I rebooted 3 servers in this way (all running Ubuntu 16.04.6 LTS) and
  all hung.

  A lot of other people are reporting the same problem at:

  https://askubuntu.com/questions/1263125/how-to-fix-a-grub-boot-error-symbol-grub-calloc-not-
  found.

  
  ---

  Above most likely means that dpkg debconf no longer knows about the
  correct drives to install grub onto.

  Please boot & mount all the target disks and execute

  $ sudo dpkg-reconfigure grub-pc

  You will be asked which drives to install grub onto, and then grub
  will be installed onto them, and more importantly, it will remember
  where to install grub to, on all future upgrades.

To manage notifications about this bug go to:
https://bugs.launchpad.net/ubuntu/+source/grub2/+bug/1889509/+subscriptions