Personally, I do not recommend cross-version upgrades, and 14.04 is an LTS version with a support period of up to 5 years. It is also inappropriate to upgrade to a non-LTS version like 15.04.
The author may consider reinstalling Ubuntu 14.04 or 15.04 without formatting. Method reference: http://my.oschina.net/eechen/blog/222841 The general idea is to back up data in the Ubuntu installation environment to a folder in the root directory For example, /mybackup, then choose not to format the installation during installation:
Personally, I do not recommend cross-version upgrades, and 14.04 is an LTS version with a support period of up to 5 years. It is also inappropriate to upgrade to a non-LTS version like 15.04.
The author may consider reinstalling Ubuntu 14.04 or 15.04 without formatting. Method reference:
http://my.oschina.net/eechen/blog/222841
The general idea is to back up data in the Ubuntu installation environment to a folder in the root directory For example, /mybackup, then choose not to format the installation during installation:
Try Linux 4.1 and above. On my 4.0.1, this happens when switching from X to tty. suspend and resume will temporarily return to normal.