False alert: read time tree block corruption

Christian Höppner
2019-12-04T11:14:11Z

Hello,

I'm writing because the kernel wiki page relating to this error[1] says to
write here first.

I'm (was) running Arch Linux, kernel 5.4.1, btrfs-progs 5.3.1

Yesterday during usage, the root file system remounted read-only. I was
dumb enough to react by rebooting the machine, when I was greeted by the
following error:

[ 25.634530] BTRFS critical (device nvme0n1p2): corrupf leaf: block=810145234944...
[ 25.634793] BTRFS error (device nvme0n1p2): block=810145234944 read time tree block corruption detected
[ 25.634961] BTRFS error (device nvme0n1p2): in __btrfs_free_extent:3080: errno=-5 IO failure
[ 25.635042] BTRFS error (device nvme0n1p2): in btrfs_run_delayed_refs:2188: errno=-5 IO failure
[ 34.653440] systemd-journald[483]: Failed to torate /var/log/journal/8f7037b10bbd4f25aadd3d19105ef920/system.journal

After booting to live media, I checked SMART, badblocks, `btrfs check
--readonly` and `btrfs scrub`. All came back clean. I conclude that this
is a false positive, and have downgraded the kernel to 5.3.13 as a
workaround.

How can I provide more information to help?

[1]: https://btrfs.wiki.kernel.org/index.php/Tree-checker#How_to_handle_such_error