Ubuntu Bug Breaks EFI on 21.04 Update With Older Machines

A partly open laptop displaying the Ubuntu logo
(Image credit: Junior Teixeira from Pexels)

The recently released Ubuntu 21.04, is the latest version of the popular Linux distribution and with the latest release we see Wayland arrive as the default display server. But it seems that those wishing to upgrade from a previous release, for example 20.04 / 20.10 are unable to. According to OMG! Ubuntu! there is a bug which is preventing users from updating to the latest release.

Ubuntu 21.04

(Image credit: Future)

The problem seems to be in shim, the bootloader which handles the secure boot process for the OS. Users running the wrong version of their EFI - an early one - can see their PC fail to boot after the upgrade. A new version of shim is on the way to fix the issue, but users who are sure their hardware is new enough to sidestep the problem can manually force an upgrade at their own risk from the command line. 

“Due to the severity of the issue we shouldn't be encouraging people to upgrade at this point in time,” wrote Canonical software engineer Brian Murray in a post to the Ubuntu Developer mailing list. “After we have a new version of shim signed will make it available in Ubuntu 21.04 and then enable upgrades.”

The exact nature of the hardware likely to fail is still unclear. We reached out to Canonical software engineer Dave Jones on Twitter, who suggested modern machines would be unaffected but older machines such as a ThinkPad 420 from 2011 and a MacBook Air from 2012 were affected by the bug.

Codenamed "Hirsute Hippo", Ubuntu 21.04 brings support for Wayland display server, with Xorg still available for those that need it. Native Active Directory integration and a performance-optimized certified Microsoft SQL Server are new features for this release.

Ian Evenden
Freelance News Writer

Ian Evenden is a UK-based news writer for Tom’s Hardware US. He’ll write about anything, but stories about Raspberry Pi and DIY robots seem to find their way to him.

  • eye4bear
    In all the alpha/beta testing no one thinks to run these updates on a couple of older PCs?
  • GoofyOne
    You remember what is was like being young .... they probably tell the boss they tested it on everything .. but .....

    I recently tried to install Kubuntu 21.04 on my machine that has x570 motherboard, with ryzen 7 2700x, rx 580x gpu, 16gb ram .... just came up with a black screen after accessing the DVD forever. Someone broke it.

    The Linux installation routines need some work, also need to standardise how they put UEFI boot loaders on and boot managers. I was trying to install several different distributions on one 1Tb hard drive ... there always seems to be some hiccup, and the UEFI boot gets corrupted, and then you can't boot any of them. The rEFInd boot manager on a USB stick might still be able to find it and boot into it though.

    {GoofyOne's 2c worth ...... grumpy today because he wasn't allowed to be sleepy, or happy ... those were already taken}