Patches supposed to address Meltdown vulnerabilities in Ubuntu 16.04 LTS have been causing issues that sound very familiar to Windows users, as several systems are no longer able to boot after installing the latest kernel updates from Canonical.
Ubuntu users have started reporting boot issues after Canonical shipped kernel updates to mitigate Meltdown, and according to bug submissions on Launchpad, systems were impacted after upgrading from kernel 4.4.0-104 to 4.4.0-108.
Canonical acknowledged the problem quickly after the first reports hit the web and shipped kernel updates 4.4.0-109 and 4.4.0-109.114 to repair the bugs, but at this point, it’s not yet known how many systems were impacted by the original boot issues. Also, there are reports that the new kernel doesn’t make any difference on a number of machines with boot failure, though this information is not yet confirmed.
The only workaround in case Canonical’s latest kernel updates don’t address the boot issue is to return to version 4.4.0-104, which appears to correct the bug, but in turn leaves computers without patches for the hardware flaws, hence exposed to any potential exploits.
As compared to similar problems experienced on Windows, the boot errors don’t seem to impact AMD systems, but Intel hardware, yet more details in this regard will probably be shared at a later time.
Windows boot issues
The boot failures that Ubuntu users are dealing with these days have been plaguing Windows users for nearly a week, though in this case only AMD systems were hit.
Microsoft was one of the first companies to ship Meltdown and Spectre patches for supported Windows versions, but shortly after making them public, users started reported boot issues on Windows 7, 8.1, and 10 computers with AMD hardware.
The software giant didn’t immediately acknowledge the issues, but earlier this week decided to pull the updates for AMD systems until a fix is developed. On Windows 10, installing the botched updates fails with an error but returning to the desktop is still possible, while on Windows 7 booting ends with a BSOD.
As it happens on Ubuntu, in the case of Windows systems hitting a Blue Screen of Death the only way to deal with the bug is to remove the patch completely, though this means that Meltdown and Spectre mitigations are pulled as well.
In case your system is affected as well and patches for the two flaws aren’t available right now, you can check out our complete guide on how to remain protected against Meltdown and Spectre vulnerabilities.