linux-kernel - swap_info_get: Bad swap offset entry 0200f8a7

lists.openwall.net		lists / announce owl-users owl-dev john-users john-dev passwdqc-users yescrypt popa3d-users / oss-security kernel-hardening musl sabotage tlsify passwords / crypt-dev xvendor / Bugtraq Full-Disclosure linux-kernel linux-netdev linux-ext4 linux-hardening linux-cve-announce PHC
Open Source and information security mailing list archives

Hash Suite: Windows password security audit tool. GUI, reports in PDF.

[<prev] [next>] [thread-next>] [day] [month] [year] [list]

Date:   Sun, 15 Oct 2017 17:17:36 -0700 (PDT)
From:   Christian Kujau <lists@...dbynature.de>
To:     linux-kernel@...r.kernel.org
cc:     Hugh Dickins <hughd@...gle.com>, Minchan Kim <minchan@...nel.org>,
        Nitin Gupta <ngupta@...are.org>,
        Robert Schelander <rschelander@....at>
Subject: swap_info_get: Bad swap offset entry 0200f8a7

Hi,

every now and then (and more frequently now) I receive the following 
message on this Atom N270 netbook:

  swap_info_get: Bad swap offset entry 0200f8a7

This started to show up a few months ago but appears to happen more 
frequently now:

      4 May  < Linux version 4.11.2-1-ARCH
      4 Jun  < Linux version 4.11.3-1-ARCH
      7 Jul  < Linux version 4.11.9-1-ARCH
      4 Aug  < Linux version 4.12.8-2-ARCH
     24 Sep  < Linux version 4.12.13-1-ARCH
    158 Oct  < Linux version 4.13.5-1-ARCH

I've only found (very) old reports for this[0][2] with either no 
solution[1] or some hinting that this may be caused by hardware errors.

In my case howerver no kernel BUG messages or oopses are involved and no
PTE errors are logged. The machine appears to be very stable, although
memory usage is quite high on that machine (but no OOM situations so
far either). As the machine is only equipped with 1GB of RAM, I'm
using ZRAM on this system, which usually looks something like this:

  $ zramctl 
  NAME       ALGORITHM DISKSIZE   DATA COMPR TOTAL STREAMS MOUNTPOINT
  /dev/zram0 lz4         248.7M 195.7M   74M 78.7M       2 [SWAP]

I suspect that, when memory pressure is high, zram may not be quick enough 
to decompress a page leading to these messages, but then I'd have expected 
a zram error message too.

Can anybody comment on these messages? If they're really indicating a 
hardware error, shouldn't there be other messages too? So far, rasdaemon 
has not logged any errors.

Thanks,
Christian.

[0] http://lkml.iu.edu/hypermail/linux/kernel/0204.3/0165.html
[1] https://bugzilla.redhat.com/show_bug.cgi?id=432337
[2] https://access.redhat.com/solutions/218733
-- 
BOFH excuse #323:

Your processor has processed too many instructions.  Turn it off immediately, do not type any commands!!