Solved the problem of freezing due to sudden "EXT4-fs error" on Ubuntu 20.04

environment

ThinkPad T14 Gen1 (AMD)

• CPU : AMD Ryzen 7 4750U
• RAM : 48GB (16GB + 32GB)
• SSD : WD SN520 512GB PCIe NVMe

phenomenon

While using Ubuntu 20.04, I suddenly get a black screen and I see multiple EXT4-fs error .... It reoccurs even if it is restarted.

Cause

According to the reference site [1], APST, a function that allows the SSD to reduce power consumption, puts the SSD to sleep and makes the root file system read-only.

solution

Check the status of APST

sudo apt install -y nvme-cli && sudo nvme get-feature -f 0x0c -H /dev/nvme0

When APST is enabled, Autonomous Power State Transition Enable (APSTE): is Enable.

Disable APST

sudo -i gedit /etc/default/grub

Add nvme_core.default_ps_max_latency_us = 0 to GRUB_CMDLINE_LINUX_DEFAULT to make it as follows.

GRUB_CMDLINE_LINUX_DEFAULT="quiet splash nvme_core.default_ps_max_latency_us=0"

After reflecting the settings with the following command, restart.

sudo update-grub

Confirm that the settings have been reflected

After restarting, recheck the APST status with the following command

sudo nvme get-feature -f 0x0c -H /dev/nvme0

Make sure Autonomous Power State Transition Enable (APSTE): is Disenable.

Reference site

[1] https://kledgeb.blogspot.com/2017/05/ubuntu-1704-66-ssd.html?m=1