Hi,

I have been trying to find out the cause of a bug that's affecting all
my external hard drive backups.

I have three external drives, in different USB enclosures, with the same
configuration and the same problem.

Drive A: 2TB HDD, USB3 Seagate self enclosed drive
Drive B: 4TB HDD, USB3 Toshiba self enclosed drive
Drive C: 512MB SSD, Crucial MX500 with USB-C third party enclosure

All of the drives have a dm-crypt / LUKS on top, with a XFS partition
inside. Drive A is a few months old, Drive B is about 3 years old, drive
C about 1.5 years old. They are seldomly used (they're backup drives) so
they are all fine mechanically.

The problem is when I attach any of the drives, enter the LUKS password
and then try to mount, this happens:
[   66.039772] XFS (dm-0): Mounting V5 Filesystem
[   66.060934] XFS (dm-0): log recovery read I/O error at daddr 0x0 len
8 error -5
[   66.060939] XFS (dm-0): empty log check failed
[   66.060940] XFS (dm-0): log mount/recovery failed: error -5
[   66.061064] XFS (dm-0): log mount failed

No matter what I do, using all the recovery tools, etc, it's impossible
to mount...

The thing is that is there is NOTHING wrong with these drives. The above
happens when running my specific, stripped and locked down kernel config.

If I take Debian's 4.19 kernel config, put it on a 5.3.11 tree, run make
oldconfig and just answer the defaults on all prompts, all of the drives
above mount fine:
[   46.184068] XFS (dm-0): Mounting V5 Filesystem
[   46.412566] XFS (dm-0): Ending clean mount

I hit this problem recently when I moved from kernel 4.18.20, which I
was using for a long time, to 5.3.X. In kernel 4.18.20, I did not have
any problems with my specific stripped down config.

I have asked for help in IRC at #xfs, and one of the guys there (ailiop)
was very helpful in trying to track down the problem, but we ultimately
failed, hence why I'm asking for help here.

I'm attaching the kernel configs and the dmesg outputs. There is nothing
obvious in the kernel config diff that should make this happen... it's a
very weird bug.

Regards,
Pedro