[arch-general] journalctl and I/O errors

[Janna Martl]

A couple months ago, I started getting I/O errors (see below) whenever
I tried to do journalctl -n X for sufficiently large X (and journalctl
would segfault). I assumed my hard drive was going to die, but in the
mean time this was annoying so I did:

# cp -rp /var/log/journal{,-clone}
# rm -rf /var/log/journal
# mv /var/log/journal{-clone,}

There were a few errors after step 1 but this made the segfaulting
stop. A few weeks later, same problem, same "fix". A few weeks later,
ditto. In all this time, the only I/O errors I've ever seen have been
related to accessing the journal. The SMART data for the drive says
that the current pending sector count is 57, but the reallocated
sector count is 0.

So if I'm reading this correctly, there have been a bunch of instances
of unreadable sectors, somehow only pertaining to one directory
despite efforts to make an independent copy of the data (which should
put it in random other sectors), but none of them have been confirmed
bad. So at this point I'm guessing it's a systemd bug (and there are
no actual bad sectors), but it would be great if someone could confirm
that any of this actually makes sense before I file a bug report based
on ignorance and speculation.

Thanks!

- J.M.



-------------------------------------------
Example I/O error:

ata1.00: exception Emask 0x0 SAct 0x0 SErr 0x0 action 0x0
ata1.00: BMDMA stat 0x5
ata1.00: failed command: READ DMA EXT
ata1.00: cmd 25/00:08:c8:ca:92/00:00:2e:00:00/e0 tag 0 dma 4096 in
         res 51/40:05:cb:ca:92/40:00:2e:00:00/ee Emask 0x9 (media error)
ata1.00: status: { DRDY ERR }
ata1.00: error: { UNC }
ata1.00: configured for UDMA/100
sd 0:0:0:0: [sda] Unhandled sense code
sd 0:0:0:0: [sda]
mResult: hostbyte=0x00 driverbyte=0x08
sd 0:0:0:0: [sda]
mSense Key : 0x3 [current] [descriptor]
mDescriptor sense data with sense descriptors (in hex):
        72 03 11 04 00 00 00 0c 00 0a 80 00 00 00 00 00
        2e 92 ca cb
sd 0:0:0:0: [sda]
mASC=0x11 ASCQ=0x4
sd 0:0:0:0: [sda] CDB:
mcdb[0]=0x28: 28 00 2e 92 ca c8 00 00 08 00
end_request: I/O error, dev sda, sector 781372107
ata1: EH complete