[BUG report] fstests/btrfs/080 fails

[BUG report] fstests/btrfs/080 fails

[Glass Su]

[-- Attachment #1: Type: text/plain, Size: 934 bytes --]


Hi

Recently I found btrfs/080 fails like:

btrfs/080 124s ... [failed, exit status 1]- output mismatch (see /root/xfstests-dev/results//btrfs/080.out.bad)
    --- tests/btrfs/080.out     2024-08-29 09:10:14.933333334 +0800
    +++ /root/xfstests-dev/results//btrfs/080.out.bad   2025-02-14 12:53:24.667572260 +0800
    @@ -1,2 +1,3 @@
     QA output created by 080
    -Silence is golden
    +Unexpected digest for file /mnt/scratch/12_52_59_984815662_snap/foobar_39
    +(see /root/xfstests-dev/results//btrfs/080.full for details)
    ...
    (Run 'diff -u /root/xfstests-dev/tests/btrfs/080.out /root/xfstests-dev/results//btrfs/080.out.bad'  to see the entire diff)
Ran: btrfs/080
Failures: btrfs/080
Failed 1 of 1 tests

It can be reproduced once in about 20 times on v6.13, misc-next(HEAD: 1c08f86eeadab89e8f6ad8559df54633afb7a3ba)
in my VM with 32 cores.

Configs and log are attached.


— 
Su


[-- Attachment #2: btrfs_080.zip --]
[-- Type: application/zip, Size: 1129771 bytes --]

[-- Attachment #3: Type: text/plain, Size: 2 bytes --]

Re: [BUG report] fstests/btrfs/080 fails

[Glass Su]

> On Feb 14, 2025, at 13:11, Glass Su <glass.su@suse.com> wrote:
> 
> 
> Hi
> 
> Recently I found btrfs/080 fails like:
> 
> btrfs/080 124s ... [failed, exit status 1]- output mismatch (see /root/xfstests-dev/results//btrfs/080.out.bad)
>    --- tests/btrfs/080.out     2024-08-29 09:10:14.933333334 +0800
>    +++ /root/xfstests-dev/results//btrfs/080.out.bad   2025-02-14 12:53:24.667572260 +0800
>    @@ -1,2 +1,3 @@
>     QA output created by 080
>    -Silence is golden
>    +Unexpected digest for file /mnt/scratch/12_52_59_984815662_snap/foobar_39
>    +(see /root/xfstests-dev/results//btrfs/080.full for details)
>    ...
>    (Run 'diff -u /root/xfstests-dev/tests/btrfs/080.out /root/xfstests-dev/results//btrfs/080.out.bad'  to see the entire diff)
> Ran: btrfs/080
> Failures: btrfs/080
> Failed 1 of 1 tests
> 
> It can be reproduced once in about 20 times on v6.13, misc-next(HEAD: 1c08f86eeadab89e8f6ad8559df54633afb7a3ba)

'misc-next' should be 'for-next'.

> in my VM with 32 cores.
> 
> Configs and log are attached.
> 
> 
> — 
> Su
> 
> <btrfs_080.zip>
> 

Re: [BUG report] fstests/btrfs/080 fails

[Qu Wenruo]

在 2025/2/14 15:41, Glass Su 写道:
>
> Hi
>
> Recently I found btrfs/080 fails like:
>
> btrfs/080 124s ... [failed, exit status 1]- output mismatch (see /root/xfstests-dev/results//btrfs/080.out.bad)
>      --- tests/btrfs/080.out     2024-08-29 09:10:14.933333334 +0800
>      +++ /root/xfstests-dev/results//btrfs/080.out.bad   2025-02-14 12:53:24.667572260 +0800
>      @@ -1,2 +1,3 @@
>       QA output created by 080
>      -Silence is golden
>      +Unexpected digest for file /mnt/scratch/12_52_59_984815662_snap/foobar_39
>      +(see /root/xfstests-dev/results//btrfs/080.full for details)
>      ...
>      (Run 'diff -u /root/xfstests-dev/tests/btrfs/080.out /root/xfstests-dev/results//btrfs/080.out.bad'  to see the entire diff)
> Ran: btrfs/080
> Failures: btrfs/080
> Failed 1 of 1 tests
>
> It can be reproduced once in about 20 times on v6.13, misc-next(HEAD: 1c08f86eeadab89e8f6ad8559df54633afb7a3ba)
> in my VM with 32 cores.
>
> Configs and log are attached.

I checked your kernel config, it looks like it has a config that is
known to cause problems:

- CONFIG_PT_RECLAIM=y

I'm unable to reproduce the bug locally, with 64 runs.
But that's with CONFIG_PT_RECLAIM=n, as I use that config to workaround
the bug.

Mind to test with either that config disabled, or apply this hotfix and
retry?

https://lore.kernel.org/linux-mm/20250211072625.89188-1-zhengqi.arch@bytedance.com/

Thanks,
Qu
>
>
> —
> Su
>
>
>
>

Re: [BUG report] fstests/btrfs/080 fails

[Glass Su]

> On Feb 14, 2025, at 13:26, Qu Wenruo <quwenruo.btrfs@gmx.com> wrote:
> 
> 
> 
> 在 2025/2/14 15:41, Glass Su 写道:
>> 
>> Hi
>> 
>> Recently I found btrfs/080 fails like:
>> 
>> btrfs/080 124s ... [failed, exit status 1]- output mismatch (see /root/xfstests-dev/results//btrfs/080.out.bad)
>>     --- tests/btrfs/080.out     2024-08-29 09:10:14.933333334 +0800
>>     +++ /root/xfstests-dev/results//btrfs/080.out.bad   2025-02-14 12:53:24.667572260 +0800
>>     @@ -1,2 +1,3 @@
>>      QA output created by 080
>>     -Silence is golden
>>     +Unexpected digest for file /mnt/scratch/12_52_59_984815662_snap/foobar_39
>>     +(see /root/xfstests-dev/results//btrfs/080.full for details)
>>     ...
>>     (Run 'diff -u /root/xfstests-dev/tests/btrfs/080.out /root/xfstests-dev/results//btrfs/080.out.bad'  to see the entire diff)
>> Ran: btrfs/080
>> Failures: btrfs/080
>> Failed 1 of 1 tests
>> 
>> It can be reproduced once in about 20 times on v6.13, misc-next(HEAD: 1c08f86eeadab89e8f6ad8559df54633afb7a3ba)
>> in my VM with 32 cores.
>> 
>> Configs and log are attached.
> 
> I checked your kernel config, it looks like it has a config that is
> known to cause problems:
> 
> - CONFIG_PT_RECLAIM=y
> 
> I'm unable to reproduce the bug locally, with 64 runs.

The test stresses CPU I guess reproduce possibility is CPU cores sensitive.

> But that's with CONFIG_PT_RECLAIM=n, as I use that config to workaround
> the bug.
> 
> Mind to test with either that config disabled, or apply this hotfix and
> retry?
> 

> https://lore.kernel.org/linux-mm/20250211072625.89188-1-zhengqi.arch@bytedance.com/
> 
Unfortunately it still fails after patching this.

— 
Su
> Thanks,
> Qu
>> 
>> 
>> —
>> Su

Re: [BUG report] fstests/btrfs/080 fails

[Filipe Manana]

On Fri, Feb 14, 2025 at 5:27 AM Qu Wenruo <quwenruo.btrfs@gmx.com> wrote:
>
>
>
> 在 2025/2/14 15:41, Glass Su 写道:
> >
> > Hi
> >
> > Recently I found btrfs/080 fails like:
> >
> > btrfs/080 124s ... [failed, exit status 1]- output mismatch (see /root/xfstests-dev/results//btrfs/080.out.bad)
> >      --- tests/btrfs/080.out     2024-08-29 09:10:14.933333334 +0800
> >      +++ /root/xfstests-dev/results//btrfs/080.out.bad   2025-02-14 12:53:24.667572260 +0800
> >      @@ -1,2 +1,3 @@
> >       QA output created by 080
> >      -Silence is golden
> >      +Unexpected digest for file /mnt/scratch/12_52_59_984815662_snap/foobar_39
> >      +(see /root/xfstests-dev/results//btrfs/080.full for details)
> >      ...
> >      (Run 'diff -u /root/xfstests-dev/tests/btrfs/080.out /root/xfstests-dev/results//btrfs/080.out.bad'  to see the entire diff)
> > Ran: btrfs/080
> > Failures: btrfs/080
> > Failed 1 of 1 tests
> >
> > It can be reproduced once in about 20 times on v6.13, misc-next(HEAD: 1c08f86eeadab89e8f6ad8559df54633afb7a3ba)
> > in my VM with 32 cores.
> >
> > Configs and log are attached.
>
> I checked your kernel config, it looks like it has a config that is
> known to cause problems:
>
> - CONFIG_PT_RECLAIM=y
>
> I'm unable to reproduce the bug locally, with 64 runs.
> But that's with CONFIG_PT_RECLAIM=n, as I use that config to workaround
> the bug.
>
> Mind to test with either that config disabled, or apply this hotfix and
> retry?
>
> https://lore.kernel.org/linux-mm/20250211072625.89188-1-zhengqi.arch@bytedance.com/

Nop, that's totally unrelated.

I've been getting the failure too, very sporadically, even before
for-next was based on 6.14-rc1/2.
The problem is due to a behaviour that changed in the buffered write
path (you did that change).

I've just sent an update to the test to make it work on 6.13+:

https://lore.kernel.org/linux-btrfs/d48dd538e99048e73973c6b32a75a6ff340e8c47.1740759907.git.fdmanana@suse.com/

Thanks.

>
> Thanks,
> Qu
> >
> >
> > —
> > Su
> >
> >
> >
> >
>
>