Ubuntu
linux package

  1. Bug #1273060
  2. Comment #15

Comment 15 for bug 1273060

Revision history for this message
Jean-Pierre van Riel (jpvr) wrote :

This bug is high risk! It's effectively bricked a Dell Latitude E6540 :-(

My theory is that, somehow, the update caused a change to the firmware NVRAM settings and boot entries for UEFI, and the Dell code can't handle something unexpected. And after I've entered BIOS password, the firmware code sadly fails to even manage to enter setup (F2) or the one time boot menu (F12). That's lousy fail-safe coding on the firmware devs part. Surely if searching NVRAM for boot options fails, that shouldn't keep the user locked out of the BIOS settings!

Here's what happened in my case:
1. Had a working install of Ubuntu Gnome 15.04 dual booting with Windows 10 and BIOS version A15 for this dell.
2. UEFI Secure Boot was enabled. The UEFI boot order priority options were set to favour the ubuntu entry (which effectively points to the EFI/ubuntu/shimx64.efi entry).
3. I ran the standard upgrade via the GUI from 15.04 to 15.10.
4. Upgrade process reported success, prompted to reboot. After a reboot, the system failed to boot into grub or anything else! Even with a UEFI compatible install CD or USB drive, I couldn't get it to boot.
5. Both F2 (BIOS setup) and F12 (one time boot menu) no longer work! This is a HUGE issue, since now I can't even use the BIOS options to change UEFI settings (e.g. look at enabled boot options, priority or disable secure boot, etc)
6. Opened up the laptop, disconnected the coin-cell CMOS battery, pressed the power button to discharge and force a BIOS settings reset (I've followed this process on many other systems to deal with a bugged out BIOS). Sadly no luck, same issue persists (I'm guessing removing the CMOS battery didn't manage to reset the NVRAM as I hoped).

What's interesting is I can take the SSD drive out, put it in a similar laptop, and it boots. It booted into Windows 10 at first, but after using settings (F2) on the working laptop, I could simply switch to the EFI/ubuntu/shimx64.efi as the first option and UEFI secure boot into Ubuntu Gnome 15.10 works fine.