* swap_info_get: Bad swap offset entry 0200f8a7
@ 2017-10-16 0:17 Christian Kujau
2017-10-20 0:33 ` Minchan Kim
2017-10-20 11:31 ` huang ying
0 siblings, 2 replies; 6+ messages in thread
From: Christian Kujau @ 2017-10-16 0:17 UTC (permalink / raw)
To: linux-kernel; +Cc: Hugh Dickins, Minchan Kim, Nitin Gupta, Robert Schelander
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!!
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: swap_info_get: Bad swap offset entry 0200f8a7
2017-10-16 0:17 swap_info_get: Bad swap offset entry 0200f8a7 Christian Kujau
@ 2017-10-20 0:33 ` Minchan Kim
2017-10-20 11:31 ` huang ying
1 sibling, 0 replies; 6+ messages in thread
From: Minchan Kim @ 2017-10-20 0:33 UTC (permalink / raw)
To: Christian Kujau
Cc: linux-kernel, Hugh Dickins, Nitin Gupta, Robert Schelander,
Andrew Morton, linux-mm, Huang, Ying
Hello,
On Sun, Oct 15, 2017 at 05:17:36PM -0700, Christian Kujau wrote:
> 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.
Since 4.11, there are lots of happenings in swap subsystem to be optimized
so it might be related to one of those changes but I'm not sure.
Worth to Ccing Huang who may know somethings since then.
Thanks.
>
> 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!!
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: swap_info_get: Bad swap offset entry 0200f8a7
@ 2017-10-20 0:33 ` Minchan Kim
0 siblings, 0 replies; 6+ messages in thread
From: Minchan Kim @ 2017-10-20 0:33 UTC (permalink / raw)
To: Christian Kujau
Cc: linux-kernel, Hugh Dickins, Nitin Gupta, Robert Schelander,
Andrew Morton, linux-mm, Huang, Ying
Hello,
On Sun, Oct 15, 2017 at 05:17:36PM -0700, Christian Kujau wrote:
> 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.
Since 4.11, there are lots of happenings in swap subsystem to be optimized
so it might be related to one of those changes but I'm not sure.
Worth to Ccing Huang who may know somethings since then.
Thanks.
>
> 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!!
--
To unsubscribe, send a message with 'unsubscribe linux-mm' in
the body to majordomo@kvack.org. For more info on Linux MM,
see: http://www.linux-mm.org/ .
Don't email: <a href=mailto:"dont@kvack.org"> email@kvack.org </a>
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: swap_info_get: Bad swap offset entry 0200f8a7
2017-10-16 0:17 swap_info_get: Bad swap offset entry 0200f8a7 Christian Kujau
2017-10-20 0:33 ` Minchan Kim
@ 2017-10-20 11:31 ` huang ying
2017-10-21 1:07 ` Christian Kujau
1 sibling, 1 reply; 6+ messages in thread
From: huang ying @ 2017-10-20 11:31 UTC (permalink / raw)
To: Christian Kujau
Cc: LKML, Hugh Dickins, Minchan Kim, Nitin Gupta, Robert Schelander
Hi, Christian,
On Mon, Oct 16, 2017 at 8:17 AM, Christian Kujau <lists@nerdbynature.de> wrote:
> 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
So you have never seen this before 4.11 like 4.10? Which operations
will trigger this error messages? Is it possible for you to check
whether the error exists for normal swap device (not ZRAM)? 32bit or
64bit kernel do you use?
Best Regards,
Huang, Ying
> 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!!
^ permalink raw reply [flat|nested] 6+ messages in thread
* Re: swap_info_get: Bad swap offset entry 0200f8a7
2017-10-20 11:31 ` huang ying
@ 2017-10-21 1:07 ` Christian Kujau
2017-10-21 16:07 ` huang ying
0 siblings, 1 reply; 6+ messages in thread
From: Christian Kujau @ 2017-10-21 1:07 UTC (permalink / raw)
To: huang ying
Cc: LKML, Hugh Dickins, Minchan Kim, Nitin Gupta, Robert Schelander
On Fri, 20 Oct 2017, huang ying wrote:
> > 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
>
> So you have never seen this before 4.11 like 4.10?
Unfortunately the kernel logs for that machine only go back until May
2017 and I cannot tell if that hasn't happened before. I've seen these
messages appear since then but didn't bother much. But as it now happens
more frequently, I thought I should mention this to the list.
> Which operations will trigger this error messages?
I'm not able to reproduce it at will, but I suspect that memory pressure
triggers these messages. The machine in question is an Lenovo Ideapad S10
notebook running 24x7 and is equipped with 1 GB of RAM. Two Java processes
are basically using up all the memory, so usually it tooks like this:
========================================
$ free -m
total used free shared buff/cache available
Mem: 994 866 67 1 60 20
Swap: 760 437 322
$ zramctl
NAME ALGORITHM DISKSIZE DATA COMPR TOTAL STREAMS MOUNTPOINT
/dev/zram0 lz4 248.7M 247M 92.3M 97.4M 2 [SWAP]
========================================
I just assumed the message is triggered when the system is really low on
memory and maybe zram is too slow to provide the memory requested. But
that's just my layman's assumption :-) For example, today's message was
emitted during the night:
Oct 20 01:26:18 len kernel: [638973.207849] \
swap_info_get: Bad swap offset entry 0200f8a7
And here are the sysstat numbers for that time frame:
$ sar -r -s 00:00 -e 02:00
Linux 4.13.5-1-ARCH (len) 10/20/2017 _i686_ (2 CPU)
12:00:01 AM kbmemfree kbmemused %memused kbbuffers kbcached kbcommit %commit kbactive kbinact kbdirty
12:10:06 AM 70076 948404 93.12 4 19004 1556176 86.58 376608 379408 220
12:20:02 AM 80488 937992 92.10 4 180404 1563952 87.01 380184 327736 5568
12:30:03 AM 83296 935184 91.82 4 137260 1569776 87.34 329512 330000 280
12:40:03 AM 65188 953292 93.60 4 21156 1571048 87.41 386644 389820 1144
12:50:03 AM 67512 950968 93.37 4 33452 1570628 87.38 378936 381580 1304
01:00:07 AM 65520 952960 93.57 4 24996 1573180 87.53 385396 386152 904
01:10:03 AM 66956 951524 93.43 4 35520 1572696 87.50 379548 379364 172
01:20:02 AM 67440 951040 93.38 4 88736 1569864 87.34 381764 370472 7080
01:30:03 AM 70048 948432 93.12 4 29212 1572504 87.49 383516 381900 1832
01:40:04 AM 71532 946948 92.98 4 29220 1570096 87.35 380120 380284 1000
01:50:03 AM 65828 952652 93.54 4 34408 1570604 87.38 381040 381028 1604
Average: 70353 948127 93.09 4 57579 1569139 87.30 376661 371613 1919
== If that is unreadable, here it is again: https://paste.debian.net/991927/
> Is it possible for you to check
> whether the error exists for normal swap device (not ZRAM)?
I have "normal" (but encrpted) swap configured but with a lower priority:
cat /proc/swaps
Filename Type Size Used Priority
/dev/dm-0 partition 524284 194348 0
/dev/zram0 partition 254616 253536 32767
I shall disable the zram device and disable encryption too and will report
back if the message appears again.
> 32bit or 64bit kernel do you use?
I'm using an i686 kernel for this Atom N270 processor (with HT enabled).
Thanks for your response,
Christian.
--
BOFH excuse #403:
Sysadmin didn't hear pager go off due to loud music from bar-room speakers.
^ permalink raw reply [flat|nested] 6+ messages in thread* Re: swap_info_get: Bad swap offset entry 0200f8a7
2017-10-21 1:07 ` Christian Kujau
@ 2017-10-21 16:07 ` huang ying
0 siblings, 0 replies; 6+ messages in thread
From: huang ying @ 2017-10-21 16:07 UTC (permalink / raw)
To: Christian Kujau
Cc: LKML, Hugh Dickins, Minchan Kim, Nitin Gupta, Robert Schelander
On Sat, Oct 21, 2017 at 9:07 AM, Christian Kujau <lists@nerdbynature.de> wrote:
> On Fri, 20 Oct 2017, huang ying wrote:
>> > 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
>>
>> So you have never seen this before 4.11 like 4.10?
>
> Unfortunately the kernel logs for that machine only go back until May
> 2017 and I cannot tell if that hasn't happened before. I've seen these
> messages appear since then but didn't bother much. But as it now happens
> more frequently, I thought I should mention this to the list.
>
>> Which operations will trigger this error messages?
>
> I'm not able to reproduce it at will, but I suspect that memory pressure
> triggers these messages. The machine in question is an Lenovo Ideapad S10
> notebook running 24x7 and is equipped with 1 GB of RAM. Two Java processes
> are basically using up all the memory, so usually it tooks like this:
>
> ========================================
> $ free -m
> total used free shared buff/cache available
> Mem: 994 866 67 1 60 20
> Swap: 760 437 322
>
> $ zramctl
> NAME ALGORITHM DISKSIZE DATA COMPR TOTAL STREAMS MOUNTPOINT
> /dev/zram0 lz4 248.7M 247M 92.3M 97.4M 2 [SWAP]
> ========================================
>
> I just assumed the message is triggered when the system is really low on
> memory and maybe zram is too slow to provide the memory requested. But
> that's just my layman's assumption :-) For example, today's message was
> emitted during the night:
>
>
> Oct 20 01:26:18 len kernel: [638973.207849] \
> swap_info_get: Bad swap offset entry 0200f8a7
>
>
> And here are the sysstat numbers for that time frame:
>
>
> $ sar -r -s 00:00 -e 02:00
> Linux 4.13.5-1-ARCH (len) 10/20/2017 _i686_ (2 CPU)
> 12:00:01 AM kbmemfree kbmemused %memused kbbuffers kbcached kbcommit %commit kbactive kbinact kbdirty
> 12:10:06 AM 70076 948404 93.12 4 19004 1556176 86.58 376608 379408 220
> 12:20:02 AM 80488 937992 92.10 4 180404 1563952 87.01 380184 327736 5568
> 12:30:03 AM 83296 935184 91.82 4 137260 1569776 87.34 329512 330000 280
> 12:40:03 AM 65188 953292 93.60 4 21156 1571048 87.41 386644 389820 1144
> 12:50:03 AM 67512 950968 93.37 4 33452 1570628 87.38 378936 381580 1304
> 01:00:07 AM 65520 952960 93.57 4 24996 1573180 87.53 385396 386152 904
> 01:10:03 AM 66956 951524 93.43 4 35520 1572696 87.50 379548 379364 172
> 01:20:02 AM 67440 951040 93.38 4 88736 1569864 87.34 381764 370472 7080
> 01:30:03 AM 70048 948432 93.12 4 29212 1572504 87.49 383516 381900 1832
> 01:40:04 AM 71532 946948 92.98 4 29220 1570096 87.35 380120 380284 1000
> 01:50:03 AM 65828 952652 93.54 4 34408 1570604 87.38 381040 381028 1604
> Average: 70353 948127 93.09 4 57579 1569139 87.30 376661 371613 1919
>
>
> == If that is unreadable, here it is again: https://paste.debian.net/991927/
>
>> Is it possible for you to check
>> whether the error exists for normal swap device (not ZRAM)?
>
> I have "normal" (but encrpted) swap configured but with a lower priority:
>
> cat /proc/swaps
> Filename Type Size Used Priority
> /dev/dm-0 partition 524284 194348 0
> /dev/zram0 partition 254616 253536 32767
>
> I shall disable the zram device and disable encryption too and will report
> back if the message appears again.
>
>> 32bit or 64bit kernel do you use?
>
> I'm using an i686 kernel for this Atom N270 processor (with HT enabled).
Thanks for your information! I have reproduced your problem. They
are just false error message. I will fix that and send out the patch
soon.
Best Regards,
Huang, Ying
^ permalink raw reply [flat|nested] 6+ messages in thread
end of thread, other threads:[~2017-10-21 16:08 UTC | newest]
Thread overview: 6+ messages (download: mbox.gz / follow: Atom feed)
-- links below jump to the message on this page --
2017-10-16 0:17 swap_info_get: Bad swap offset entry 0200f8a7 Christian Kujau
2017-10-20 0:33 ` Minchan Kim
2017-10-20 0:33 ` Minchan Kim
2017-10-20 11:31 ` huang ying
2017-10-21 1:07 ` Christian Kujau
2017-10-21 16:07 ` huang ying
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