From: David Sterba <dsterba@suse.cz>
To: Laszlo Fiat <laszlo.fiat@gmail.com>
Cc: linux-btrfs@vger.kernel.org
Subject: Re: errors with linux-next-20160701
Date: Fri, 8 Jul 2016 15:51:08 +0200 [thread overview]
Message-ID: <20160708135108.GH13336@twin.jikos.cz> (raw)
In-Reply-To: <CA+7w51htypyk_RAUmf0i_12JSawq0BvKckSUk=sqyLHVkwvJNA@mail.gmail.com>
On Thu, Jul 07, 2016 at 08:15:18PM +0200, Laszlo Fiat wrote:
> I have a simple btrfs filesystem on a single device. It worked well so far.
>
> Recently I compiled a new kernel linux-next-20160701, with this new
> kernel I get warnings and errors in the logs.
I hope you're aware that using linux-next can lead to all sorts of
problems.
> But btrfs scrub
> completes with 0 errors, and if I boot back to the older
> linux-next-20160527 kernel, there are no error messages in the logs
> when using it or running scrub.
There's other involved party, device mapper so this is another factor to
be taken into account when you compare the kernels.
> The filesystem is mountable
> read-write, but I am worried about the warnings and errors. The
> checksum warnings always come up with new numbers, never the same.
This looks likes random memory overwrites, but that's just a guess.
> $ uname -a
> Linux debian 4.7.0-rc5-next-20160701+ #46 SMP Sun Jul 3 15:29:10 CEST
> 2016 x86_64 GNU/Linux
>
> $ btrfs --version
> btrfs-progs v4.5.2
>
> # btrfs fi show
> Label: none uuid: d6cab9ca-5e89-4d8c-b55b-c700a6096d37
> Total devices 1 FS bytes used 55.31GiB
> devid 1 size 119.23GiB used 62.07GiB path /dev/mapper/home
>
> # btrfs fi df /home
> Data, single: total=59.01GiB, used=54.86GiB
> System, DUP: total=32.00MiB, used=16.00KiB
> Metadata, DUP: total=1.50GiB, used=462.56MiB
> GlobalReserve, single: total=88.42MiB, used=0.00B
>
> # dmesg | grep Btrfs
> [ 4.530960] Btrfs loaded, crc32c=crc32c-intel
>
> # dmesg | grep BTRFS
> [ 4.530968] BTRFS: selftest: sectorsize: 4096 nodesize: 4096
> [ 4.530973] BTRFS: selftest: sectorsize: 4096 nodesize: 8192
> [ 4.530978] BTRFS: selftest: sectorsize: 4096 nodesize: 16384
> [ 4.530982] BTRFS: selftest: sectorsize: 4096 nodesize: 32768
> [ 4.530986] BTRFS: selftest: sectorsize: 4096 nodesize: 65536
> [ 52.114886] BTRFS: device fsid d6cab9ca-5e89-4d8c-b55b-c700a6096d37
> devid 1 transid 29825 /dev/dm-0
> [ 60.598254] BTRFS info (device dm-0): use lzo compression
> [ 60.598266] BTRFS info (device dm-0): disk space caching is enabled
> [ 60.598273] BTRFS info (device dm-0): has skinny extents
> [ 60.797475] BTRFS warning (device dm-0): dm-0 checksum verify
> failed on 343146496 wanted D962670F found 32292342 level 0
> [ 60.850008] BTRFS info (device dm-0): detected SSD devices, enabling SSD mode
> [ 165.491150] BTRFS error (device dm-0): bad tree block start
> 8242807833012638730 658522112
A quick sanity check of the values:
8242807833012638730 == 0x7264560d4686940a
which does not look like a valid block pointer (as it's supposed to be
aligned to 4k, ie. ending with 000). This looks like the block has been
overwritten externally.
> # grep "BTRFS error" /var/log/syslog.1
> Jul 6 19:35:23 debian kernel: [ 2712.823929] BTRFS error (device
> dm-0): bad tree block start 10283429131165574676 662503424
> Jul 6 19:35:23 debian kernel: [ 2712.850468] BTRFS error (device
> dm-0): bad tree block start 14801127411347629381 663502848
> Jul 6 19:35:23 debian kernel: [ 2712.888038] BTRFS error (device
> dm-0): bad tree block start 9855282569545798023 664141824
> Jul 6 19:35:23 debian kernel: [ 2712.888491] BTRFS error (device
> dm-0): bad tree block start 12220505751590977444 664207360
> Jul 6 19:35:59 debian kernel: [ 2748.728044] BTRFS error (device
> dm-0): bad tree block start 16324583772582058537 665927680
> Jul 6 19:37:31 debian kernel: [ 2840.465648] BTRFS error (device
> dm-0): bad tree block start 13618790082605902229 309936128
> Jul 6 19:37:31 debian kernel: [ 2840.465672] BTRFS error (device
> dm-0): bad tree block start 9260130888975445835 309870592
> Jul 6 19:37:31 debian kernel: [ 2840.466526] BTRFS error (device
> dm-0): bad tree block start 17351834078110360434 309968896
> Jul 6 19:37:31 debian kernel: [ 2840.466579] BTRFS error (device
> dm-0): bad tree block start 3476538019772833052 309985280
> Jul 6 19:37:31 debian kernel: [ 2840.509021] BTRFS error (device
> dm-0): bad tree block start 1881224518785478735 327696384
> Jul 6 19:37:31 debian kernel: [ 2840.509085] BTRFS error (device
> dm-0): bad tree block start 14212257183956925500 327712768
> Jul 6 19:37:31 debian kernel: [ 2840.533393] BTRFS error (device
> dm-0): bad tree block start 13574459615317154064 331268096
> Jul 6 19:37:53 debian kernel: [ 2862.852848] BTRFS error (device
> dm-0): bad tree block start 13618790082605902229 309936128
> Jul 7 19:52:05 debian kernel: [ 165.491150] BTRFS error (device
> dm-0): bad tree block start 8242807833012638730 658522112
The other 'start' values are also bogus block pointers.
I don't see an apparent cause of the errors, but this kind of reports
usually points to external factors, so I don't think it's a btrfs bug.
next prev parent reply other threads:[~2016-07-08 13:50 UTC|newest]
Thread overview: 3+ messages / expand[flat|nested] mbox.gz Atom feed top
2016-07-07 18:15 errors with linux-next-20160701 Laszlo Fiat
2016-07-08 13:51 ` David Sterba [this message]
2016-07-08 13:57 ` Chris Mason
Reply instructions:
You may reply publicly to this message via plain-text email
using any one of the following methods:
* Save the following mbox file, import it into your mail client,
and reply-to-all from there: mbox
Avoid top-posting and favor interleaved quoting:
https://en.wikipedia.org/wiki/Posting_style#Interleaved_style
* Reply using the --to, --cc, and --in-reply-to
switches of git-send-email(1):
git send-email \
--in-reply-to=20160708135108.GH13336@twin.jikos.cz \
--to=dsterba@suse.cz \
--cc=laszlo.fiat@gmail.com \
--cc=linux-btrfs@vger.kernel.org \
/path/to/YOUR_REPLY
https://kernel.org/pub/software/scm/git/docs/git-send-email.html
* If your mail client supports setting the In-Reply-To header
via mailto: links, try the mailto: link
Be sure your reply has a Subject: header at the top and a blank line
before the message body.
This is a public inbox, see mirroring instructions
for how to clone and mirror all data and code used for this inbox;
as well as URLs for NNTP newsgroup(s).