mjhjmtu

I have lots of these messages in my journal:

kernel: BTRFS critical (device dm-5): corrupt leaf: root=5 block=879480373248 slot=55 ino=820922, name hash mismatch with key, have 0x00000000e1726375 expect 0x0000000030b05af8

Occasionally, the file system will, apparently spontaneously (but probably in connection to these messages), switch into read-only mode, which is fairly annoying because I only start noticing it once I already have something I’d like to save, and a reboot seems to be the only solution. Apart from that, though, the file system appears to function normally, so I’m not convinced those messages are quite as critical as they sound.

A btrfs scrub doesn’t help (“total bytes scrubbed: 894.66GiB with 0 errors”).

What options do I have to address this? The file system in question is the root file system, and I’d prefer to not have to reinstall my system, mainly because I currently don’t have enough free space on external disks.

The message is always identical, so the problem only seems to affect the one block mentioned. If I’m guessing correctly that ino= refers to an inode number, then the affected path seems to be one I don’t really care about (command courtesy of this answer):

$ sudo btrfs inspect-internal inode-resolve 820922 /
//home/[user name]/.cache/mozilla/firefox/[profile name]/cache2/entries

Trying to list entries of that directory will cause ls to spew out a bunch of EIO errors while trying to stat some of the files in the directory. Switching to long output format makes it clearer that most files in the directory are not affected – it’s just a few files where permissions, owner and timestamp are a bunch of question marks, between a lot more files where the metadata is intact and readable.

I could try to delete those entries that seem to be unstatable, or even the entire directory, since it’s just a cache anyways, apparently. But before I try it and potentially wreak more havoc on an already damaged portion of the file system – does anyone know if that’s a good idea or not? Or other ideas for investigating this situation?