How to resolve a frozen Linux directory unmounting issue?

If Linux freezes when unmounting a directory, you can try the following methods to resolve the issue:

1. Forcefully unmount a directory using the “umount -l” command: Enter the command “umount -l directory path” in the terminal, where the directory path is the path of the directory that needs to be unmounted. This command will unmount the directory forcefully, even if it is being used.
2. Use the “fuser -mv” command to check the usage of a directory and release it: Input the command “fuser -mv directory path” in the terminal to see which processes are using that directory. Then, either end those processes or have them release their usage of the directory before attempting to unmount the directory.
3. Force unmount a directory using the command “umount -f”: Input the command “umount -f directory path” in the terminal. This command will forcefully unmount the directory, even if it is currently in use. However, it is important to note that this command may lead to data loss or other issues, so it is recommended to only use it as a last resort.

If the above methods still cannot resolve the issue, you can try restarting the system and then attempt to unmount the directory. If the problem persists, further investigation into system or file system issues may be necessary.