新安装了带有 5.13.0-27 内核的 20.04.3 LTS？

Question

我有两台戴尔笔记本电脑：

1. 笔记本电脑 A（戴尔笔记本电脑）大约一年前从 18.04.x LTS 升级到 20.04.3 LTS。这有：

Linux 5.4.0-96-generic #109-Ubuntu SMP Wed Jan 12 16:49:16 UTC 2022 x86_64 x86_64 x86_64 GNU/Linux

2. 笔记本电脑 B，一台新的戴尔笔记本电脑，装有 Windows11，并通过实时 USB 安装了 Ubuntu 20.04.3 LTS 将其清除。在安装过程中，我选择了从存储库自动升级的选项。这款新笔记本电脑具有以下内核：

Linux 5.13.0-27-generic #29~20.04.1-Ubuntu SMP Fri Jan 14 00:32:30 UTC 2022 x86_64 x86_64 x86_64 GNU/Linux

上述两款笔记本电脑均具有：

$ cat /etc/lsb-release 
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=20.04
DISTRIB_CODENAME=focal
DISTRIB_DESCRIPTION="Ubuntu 20.04.3 LTS"

两者都启用了实时补丁。

The question is: What am I missing that as to why does laptop A ( in item [1] ) never upgrades the kernel to 5.13.x like what laptop B have when laptop B is freshly installed ?

I literally type:

sudo apt-get update
sudo apt-get upgrade

... everyday on laptop A. Although it upgrades to the latest 5.4.x kernel ... never upgrades to 5.13.x kernel.

Answer 1

Ubuntu LTS releases have two main kernel stack choices

GA or the general kernel stack

This kernel stack remains the same for the life of the product. For Ubuntu 20.04 LTS it will use the 5.4 kernel.

HWE or hardware enablment stack

This kernel stack will change as the release advances.

At

• 20.04.2 it uses the 5.8 kernel stack from Ubuntu 20.10
• 20.04.3 it uses the 5.11 kernel stack from Ubuntu 21.04
• 20.04.4 it uses the 5.13 kernel stack from Ubuntu 21.10 (20.04 or focal is progressing to 20.04.4 currently with some of the packages already installed)
• 20.04.5 will use the 5.15 kernel stack from Ubuntu 22.04 LTS (the GA stack for 22.04).

See https://wiki.ubuntu.com/Kernel/LTSEnablementStack for details.

Ubuntu Server installs default to the more stable GA stack, but it can be changed at install, and post-install.

Ubuntu Desktop installs default to the HWE stack by default, but can be changed post-install.

Ubuntu flavors can vary depending on media; I'll use Lubuntu 20.04 as example.

• Lubuntu 20.04 & 20.04.1 media defaults to GA kernel stack for new installs
• Lubuntu 20.04.2 & later media defaults to HWE kernel stack for new installs.

Other OEM kernel stacks can also be used for new installs; if the installer detects your hardware as benefiting from an OEM kernel.

You can have both kernel stacks (GA & HWE) installed on a system as well; meaning you'll have more to upgrade (both will get updates), but the bandwidth & disk space used isn't that great; you select at boot (ie. grub) which you'll use. However do note some closed-source or proprietary video drivers do not allow both stacks to co-exist.

请参阅提供的 wiki 页面如何安装/切换安装；例如。要从 HWE 切换到 GA（对于 Ubuntu Desktop 20.04 LTS），请搜索“从 HWE/OEM 降级到 GA 内核： ”