I started with Ubuntu and later tried Linux Mint because I wanted a stable everyday system that felt better than Windows. Both distributions worked well until a system update caused my laptop's display brightness to remain stuck at 100%. The laptop uses Intel integrated graphics, so I wasn't expecting major compatibility problems.
After trying several fixes, I eventually solved the issue by booting an older 6.x kernel instead of the newer 7.x kernel. I'm not especially experienced with Linux, and although the older kernel works, I'm worried that staying on it could mean missing security updates or important fixes. That concern led me to reinstall Windows, even though I would rather use Linux.
Is an older kernel necessarily less secure? Do Ubuntu and Mint continue providing security updates for their older supported kernel branches, and could this brightness problem be a kernel bug that has since been fixed?
4 Answers
If multiple kernels are installed, you can usually select the working one from the boot menu and keep the newer one available for testing. You do not necessarily have to reinstall the operating system. If you later try another distribution, its kernel packaging and update schedule may differ, but the same hardware-specific brightness issue could still appear because the underlying firmware and laptop design remain the same.
This sounds like a regression in the newer kernel or a graphics/backlight configuration issue, rather than proof that Linux is unsuitable. Brightness control can depend on the laptop firmware, ACPI behavior, graphics driver, and kernel parameters. Keeping the known-good kernel as the default is a reasonable temporary workaround, while checking release notes, filing a bug with hardware details and logs, or testing a later kernel may eventually resolve it.
I did spend a lot of time troubleshooting and was glad when rolling back the kernel finally fixed it. My main concern was security, since I wasn't familiar enough with Linux to know whether an older kernel was still maintained.
Using an older kernel does not automatically mean using an insecure system. Ubuntu and Mint maintain the kernel branch associated with a supported release and backport security fixes for it until that release reaches end of life. You may miss newer features and hardware support, but the kernel can still receive security updates. The important distinction is whether you are using a maintained distribution kernel, not simply an abandoned old build.
The version number can be misleading. Linux has several long-term-support branches maintained at the same time, sometimes for years. A stable LTS branch is commonly used in production systems, so there is no need to chase the newest kernel if it causes a regression. Keep the working kernel installed, continue applying normal system updates, and periodically test newer kernels when they become available.
I may try Linux again and test another distribution, but I mainly wanted to understand whether the kernel workaround left me exposed to security problems.