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My Acer laptop (Ubuntu 18.04.3 LTS) fails to boot with new kernels 5.0.0-23 and 5.0.0-25. It boots normally with the old kernel 4.18.0-25.

Kernel 5.0.0-23 was installed prior to rebooting on 8/6/19. Kernel 5.0.0-25 was installed today (8/13/19).

I had been periodically booting with kernel 4.18.0-25, running Software Updater, and seeing if that fixed the problem. It didn't. (I am currently using a different computer for most purposes.) Today Software Updater installed the newest kernel, 5.0.0-25. When I restarted the laptop after the update, booting failed in the same way as it did for 5.0.0-23.

Now I will keep the laptop disconnected from the Internet, and not allow any more updates until I find out how to prevent updates from removing old kernels. I don't want to lose 4.18.0-25. I expected it to be gone today after the update, since updates had been saving only one old kernel, but fortunately it is still there. (Three kernels are present.)

Here is a short description of the problem.

When I boot with kernel 5.0.0-23, the screen goes dark and the power light turns off about 20 seconds after I select Ubuntu from the Grub menu.

When I boot with kernel 5.0.0-23 in recovery mode, the same thing happens after about 80 seconds, which is well after the Recovery Menu appears. The Recovery Menu screen has a few boot messages scattered diagonally across it, and has some other display problems.

History: On Tuesday 8/6/19, Software Updater appeared, and told me that it had updates and that the computer needed to restart to finish installing previous updates. I selected "Remind Me Later" but went ahead and restarted the laptop, which failed when booting, as described above.

This is dual-boot with Windows 10. Windows boots normally. The Ubuntu 18.04.2 LTS boot/install USB stick that I used for installing Ubuntu boots normally.

Acer Aspire 3 A315-51-361T (purchased new about a year ago)

Ubuntu 18.04.3 LTS

Secure Boot is enabled

What might be causing this problem? And what should I do about it?

bnjsfdls
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  • Use the 4.15 kernel, that will get updates till Ubuntu 18.04 EoL. – Pilot6 Aug 13 '19 at 19:14
  • Or better yet, report a bug? – dobey Aug 13 '19 at 19:33
  • Boot to 4.15 and in terminal type sudo dmidecode -s bios-version to get the current BIOS version. Then go to the Acer web site and see if there's a newer BIOS for your computer. Report back. – heynnema Aug 13 '19 at 19:52
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    @heynnema I'm hesitant to update the BIOS. I've never done that. Linux has worked for me for almost 20 years without me having to do that. I also don't think I've ever had a time in all those years when Linux failed to boot. – bnjsfdls Aug 13 '19 at 20:21
  • @Pilot6 Thanks. I'll look into that. I need to find out more about installing old kernels. – bnjsfdls Aug 13 '19 at 20:28
  • But you weren't running kernel 5.x.x were you? Did you check for a newer BIOS using my instructions. This would be moot if there's no newer BIOS for your machine. – heynnema Aug 13 '19 at 20:28
  • @heynnema I used your command to get the BIOS version, then went to the Acer web site but I didn't see where to find out whether there was a new version. Since I really want to avoid updating the BIOS, it didn't seem worth it to spend more time at that. – bnjsfdls Aug 13 '19 at 20:33
  • What BIOS version do you currently have? – heynnema Aug 13 '19 at 20:39
  • According to https://www.acer.com/ac/en/GB/content/support-product/7210?b=1 BIOS 1.14, released 3/29/19 is the current version. – heynnema Aug 13 '19 at 20:42
  • Just a week ago I helped a user with exactly the same problem as yourself... kernel 5.x.x... and the BIOS fixed their problem. Don't completely rule it out. – heynnema Aug 13 '19 at 20:55
  • Please have a look at https://askubuntu.com/questions/987051/how-to-keep-4-linux-kernels-in-boot-by-default-before-they-are-removed-automati to address your concern on how to prevent updates from removing old kernels. – Raffa Aug 14 '19 at 00:01
  • @Pilot6 From what I've read, it seems clear that if I reinstall Ubuntu with an 18.04.1 LTS iso I will get the desired result of kernel 4.15 with its long-term updates. Alternatively, it sounds like it might also be possible to alter the existing installed Ubuntu 18.04.3 LTS to get that result, but I'm unclear on how that might be done. Do you have any suggestions for that? – bnjsfdls Sep 09 '19 at 18:25

2 Answers2

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From the comments...

I strongly suspect that your problem booting with the 5.x.x kernels is due to you possibly having an older BIOS that needs updating.

Boot to the 4.18.0-25 kernel, and in the terminal type sudo dmidecode -s bios-version to get the current BIOS version. Then go to the Acer web site and see if there's a newer BIOS for your computer.

According to https://www.acer.com/ac/en/GB/content/support-product/7210?b=1 BIOS 1.14, released 3/29/2019 is the current version.

Update #1:

The user has reported that their current BIOS is version 1.05.

heynnema
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  • Both AMD & Intel based (Actually almost all CPUs) systems need updates: Systems need UEFI updates, anyway, for mitigation of Meltdown and Spectre CPU vulnerabilities from cpu speculative execution and caching. Ubuntu kernel & Windows have had updates for these issues, but new variants seem to be found so future updates may also be required. – oldfred Aug 13 '19 at 21:54
  • @heynnema Thank you for the info. My laptop's BIOS is version 1.05. I might eventually try updating the BIOS. But before I risk bricking my laptop by doing that I'll need to find out more info about it, since I've never done it before and am not comfortable with it yet. I'll look into it some more. – bnjsfdls Aug 24 '19 at 13:54
  • @bnjsfdls Good for you. As always, it's a good idea to make good backups first. Assuming that it's done correctly, as per the manufacturer's instructions, BIOS updates are simple and quick... and hopefully it'll solve your boot problem. Report back. – heynnema Aug 24 '19 at 14:08
  • @heynnema I found more info and was ready to try the BIOS update. Then I decided I should first make sure that I could downgrade the BIOS back to 1.05 if the update caused new problems. I was surprised to find that I would probably not be able to do that. For me, now there is a very high requirement for certainty that the BIOS update would fix the current problem and that it would not cause new problems. I don't have anywhere near enough certainty to proceed. I'm sorry. – bnjsfdls Aug 31 '19 at 11:58
  • @bnjsfdls You're way overthinking all of this. You're way behind in BIOS updates that should have been done over time. Make a good backup of your important stuff, then just jump in and do the BIOS update. If you don't need/want it to possibly fix the kernel 5.x.x boot problem, you'll want it for the security updates so you don't get hacked. – heynnema Aug 31 '19 at 13:41
  • FYI The OP has just answered the question. Turns out to be kernel bug. – WinEunuuchs2Unix Sep 24 '19 at 22:01
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It turns out that my original plan of periodically booting with kernel 4.18.0-25, running Software Updater, and seeing if that fixed the problem, eventually produced the desired result.

The arrival of kernel 5.0.0-29 solved the problem. The laptop now boots normally, using kernel 5.0.0-29. Everything seems back to normal.

Back in August, when I found out that kernel 4.18.0-25 would continue to be saved during updates (because I was booting from it when running those updates), I resumed periodically connecting to the Internet and running Software Updater. The latest kernel update installed kernel 5.0.0-29. (Kernel 5.0.0-27 had failed in the same way as the previous two 5.0.0 kernels.)

So, now I will use the laptop normally, and do updates normally. I expect kernel 4.18.0-25 to disappear with the next kernel update, and that will be OK, since kernel 5.0.0-29 works on my laptop.

The comments at the beginning of the script /etc/kernel/postinst.d/apt-auto-removal explain which kernels are saved during kernel updates.

bnjsfdls
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  • @Raffa Thanks. The question in your comment, and other questions, pointed me to the relevant script. From the comments in that script it was clear to me that kernel 4.18.0-25 would continue to be saved as long as it was the only kernel that could successfully boot the laptop (which guaranteed that it would be the kernel running during updates). – bnjsfdls Sep 24 '19 at 18:26