Re: [PATCH] Add RAID 1 chunksize test

[Jes Sorensen <jes@trained-monkey.org>]

On 4/4/22 08:38, Doug Ledford wrote:
> On Mon, 2022-04-04 at 09:08 +0200, Mateusz Kusiak wrote:
>> Specifying chunksize for raid 1 is forbidden.
>> Add test for blocking raid 1 creation with chunksize.
>>
>> Signed-off-by: Mateusz Kusiak <mateusz.kusiak@intel.com>
>> ---
>>  tests/01r1create-chunk | 15 +++++++++++++++
>>  1 file changed, 15 insertions(+)
>>  create mode 100644 tests/01r1create-chunk
>>
>> diff --git a/tests/01r1create-chunk b/tests/01r1create-chunk
>> new file mode 100644
>> index 00000000..717a5e5a
>> --- /dev/null
>> +++ b/tests/01r1create-chunk
>> @@ -0,0 +1,15 @@
>> +# RAID 1 volume, 2 disks, chunk 64
>> +# NEGATIVE test - creating raid 1 with chunksize specified is
>> forbidden
>> +
>> +num_disks=2
>> +level=1
>> +device_list="$dev0 $dev1"
>> +chunk=64
>> +
>> +# Create raid 1 with chunk 64k and fail
>> +if ! mdadm --create --run $md0 --auto=md --level=$level --
>> chunk=$chunk --raid-disks=$num_disks $device_list
>> +then
>> +       exit 0
>> +fi
>> +
>> +exit 1
> 
> This is a case of overkill IMO.  Chunk size with raid1 isn't really a
> problem and shouldn't result in mdadm refusing to work.  Chunk size with
> raid1 simply has no effect and should just be ignored with at most a
> warning by mdadm.

I agree with Doug here. I think a warning from mdadm that chunksize
makes no sense for raid1 would be good, but having a failed test over it
makes little sense. If anything the test should detect the warning is
happening.

Thanks,
Jes