ext4 /Home filesystem won't mount - possible to recover?

Question

I am using Pop! OS on a workstation PC in my workplace. However, today the machine crashed into a recovery mode on boot, apparently because the /Home filesystem wouldn't mount. The filesystem is ext4 and is in a partition on an NVME SSD.

When I try to mount the partition manually as root, I get the following error:

mount: /home: wrong fs type, bad option, bad superblock on /dev/nvme0n1p4, missing codepage or helper program, or other error.

dmesg shows the following lines that seem to be relevant:

[  193.536359] EXT4-fs warning (device nvme0n1p4): ext4_enable_quotas:7092: Failed to enable quota tracking (type=0, err=-22, ino=3). Please run e2fsck to fix.
[  193.536593] EXT4-fs (nvme0n1p4): mount failed
[  316.932127] kauditd_printk_skb: 17 callbacks suppressed
[  316.932131] audit: type=1400 audit(1717275233.956:29): apparmor="DENIED" operation="file_inherit" class="file" profile="man_groff" name="/dev/tty1" pid=1149 comm="preconv" requested_mask="wr" denied_mask="wr" fsuid=0 ouid=0
[  316.935702] audit: type=1400 audit(1717275233.960:30): apparmor="DENIED" operation="file_inherit" class="file" profile="man_groff" name="/dev/tty1" pid=1150 comm="tbl" requested_mask="wr" denied_mask="wr" fsuid=0 ouid=0
[  316.939852] audit: type=1400 audit(1717275233.964:31): apparmor="DENIED" operation="file_inherit" class="file" profile="man_groff" name="/dev/tty1" pid=1158 comm="troff" requested_mask="wr" denied_mask="wr" fsuid=0 ouid=0
[  354.323345] EXT4-fs warning (device nvme0n1p4): ext4_enable_quotas:7092: Failed to enable quota tracking (type=0, err=-22, ino=3). Please run e2fsck to fix.
[  354.323699] EXT4-fs (nvme0n1p4): mount failed
[  650.591473] EXT4-fs warning (device nvme0n1p4): ext4_enable_quotas:7092: Failed to enable quota tracking (type=0, err=-22, ino=3). Please run e2fsck to fix.
[  650.591697] EXT4-fs (nvme0n1p4): mount failed

I tried running e2fsck, as the messages suggest. It didn't report any errors - just said the journal was recovered and reported numbers of nodes and files. However, the partition still wouldn't mount afterwards.

There are other partitions on the drive that did seem to mount fine. It seems strange, because everything was working until I shut the machine down for maintenance. But then, when I tried to power back on, this error occurred.

Does this likely mean the SSD is failing and should be replaced? Are there any (simple) options for recovering the filesystem/data?

Update:

Per the dmesg log, the issue seems to relate to user quotas. I have user quotas enabled on the /home partition, but I'm not sure where this mounting error is suddenly coming from. Does anyone have any ideas of what I can try?

Answer 1

This error indicates issues when mounting the EXT4 filesystem. The error "wrong fs type, bad option, bad superblock" suggests there might be a problem with the filesystem or the drive itself.

To resolve this issue, you can try the following steps:

1. Check filesystem integrity: Run the e2fsck command to check and fix issues in the filesystem.

2. Fix quota problems: The error mentions issues related to enabling quotas on the filesystem. You can try fixing this by either disabling quotas temporarily or addressing the problem. For instance, you can temporarily disable quotas by running quotaoff command.

3. Check device problems: Since NVME drives can enter read-only mode for protection, try gathering more information using smartctl -a command and look for problems.

If the issue persists after trying these steps, it could indicate more serious hardware issues with the disk. In this case, the solution would involve cloning the drive using tools like dd_rescue to a healthy drive and then attempting to run fsck again to fix the issues and remount the filesystem.