Re: [PATCH v2 1/2] f2fs/006: add testcase to check out-of-space case

[Chao Yu <chao@kernel.org>]

On 2024/10/25 11:44, Zorro Lang wrote:
> On Wed, Oct 23, 2024 at 04:16:01PM +0800, Chao Yu wrote:
>> This is a regression test to check whether f2fs handles dirty
>> data correctly when checkpoint is disabled, if lfs mode is on,
>> it will trigger OPU for all overwritten data, this will cost
>> free segments, so f2fs must account overwritten data as OPU
>> data when calculating free space, otherwise, it may run out
>> of free segments in f2fs' allocation function, resulting in
>> panic.
>>
>> Cc: Jaegeuk Kim <jaegeuk@kernel.org>
>> Signed-off-by: Chao Yu <chao@kernel.org>
>> ---
>> v2:
>> - add _fixed_by_kernel_commit()
>> - use _scratch_mkfs_sized() rather than formating size-specified
>> loop device
>> - code cleanup
>>   tests/f2fs/006     | 38 ++++++++++++++++++++++++++++++++++++++
>>   tests/f2fs/006.out |  6 ++++++
>>   2 files changed, 44 insertions(+)
>>   create mode 100755 tests/f2fs/006
>>   create mode 100644 tests/f2fs/006.out
>>
>> diff --git a/tests/f2fs/006 b/tests/f2fs/006
>> new file mode 100755
>> index 00000000..63d00018
>> --- /dev/null
>> +++ b/tests/f2fs/006
>> @@ -0,0 +1,38 @@
>> +#! /bin/bash
>> +# SPDX-License-Identifier: GPL-2.0
>> +# Copyright (c) 2024 Oppo.  All Rights Reserved.
>> +#
>> +# FS QA Test No. f2fs/006
>> +#
>> +# This is a regression test to check whether f2fs handles dirty
>> +# data correctly when checkpoint is disabled, if lfs mode is on,
>> +# it will trigger OPU for all overwritten data, this will cost
>> +# free segments, so f2fs must account overwritten data as OPU
>> +# data when calculating free space, otherwise, it may run out
>> +# of free segments in f2fs' allocation function, resulting in
>> +# panic.
>> +#
>> +. ./common/preamble
>> +_begin_fstest auto quick
>> +
>> +_fixed_by_kernel_commit xxxxxxxxxxxx \
>> +	"f2fs: fix to account dirty data in __get_secs_required()"
>> +
>> +testfile=$SCRATCH_MNT/testfile
>> +
>> +_require_scratch
>> +_scratch_mkfs_sized $((1024*1024*100)) >> $seqres.full
>> +
>> +# use mode=lfs to let f2fs always triggers OPU
>> +_scratch_mount -o mode=lfs,checkpoint=disable:10%,noinline_dentry >> $seqres.full
>> +
>> +dd if=/dev/zero of=$testfile bs=1M count=50 2>/dev/null
>> +
>> +# it may run out of free space of f2fs and hang kernel
>> +dd if=/dev/zero of=$testfile bs=1M count=50 conv=notrunc conv=fsync
>> +dd if=/dev/zero of=$testfile bs=1M count=50 conv=notrunc conv=fsync
> 
> What kind of failure should be printed at here if test on unfixed kernel?

It will panic kernel w/o fix, can you please check dmesg?

> I got:
> 
> # diff -u /root/git/xfstests/tests/f2fs/006.out /root/git/xfstests/results//default/f2fs/006.out.bad|less
> --- /root/git/xfstests/tests/f2fs/006.out       2024-10-25 11:33:54.693883281 +0800
> +++ /root/git/xfstests/results//default/f2fs/006.out.bad        2024-10-25 11:34:55.907252401 +0800
> @@ -1,6 +1,6 @@
>   QA output created by 006
>   50+0 records in
>   50+0 records out
> -dd: error writing '/mnt/scratch_f2fs/testfile': No space left on device
> -3+0 records in
> -2+0 records out
> +dd: fsync failed for '/mnt/scratch/testfile': Input/output error
> +50+0 records in
> +50+0 records out
> 
> Does that mean the bug is reproduced?
 > >> +
>> +_scratch_remount checkpoint=enable
>> +
>> +status=0
>> +exit
>> diff --git a/tests/f2fs/006.out b/tests/f2fs/006.out
>> new file mode 100644
>> index 00000000..0d7b3910
>> --- /dev/null
>> +++ b/tests/f2fs/006.out
>> @@ -0,0 +1,6 @@
>> +QA output created by 006
>> +50+0 records in
>> +50+0 records out
>> +dd: error writing '/mnt/scratch_f2fs/testfile': No space left on device
> 
> The "/mnt/scratch_f2fs" should be SCRATCH_MNT, please use _filter_scratch()
> by importing common/filter.

Correct, let me fix this.

Thanks,

> 
>> +3+0 records in
>> +2+0 records out
>> -- 
>> 2.40.1
>>
>