Coupled Layer MSR: PR 14300, ECSubRead decode fail.

Coupled Layer MSR: PR 14300, ECSubRead decode fail.

[Myna V]

Hello All,

This is regarding the make check error in readable.sh

https://jenkins.ceph.com/job/ceph-pull-requests/21319/

We have added additional fields to the ECSubRead message type and
updated the encode, decode of ECSubRead message to incorporate the
newly added fields. The failure seems to happen when the object (older
ECSubRead) is being decoded with the new decode function as it is
expecting a larger buffer length.

How do we update the test objects in ceph-object-corpus with these
added fields ?

Thanks,
Myna.

Re: Coupled Layer MSR: PR 14300, ECSubRead decode fail.

[Gregory Farnum]

On Mon, Apr 3, 2017 at 11:02 AM, Myna V <mynaramana@gmail.com> wrote:
> Hello All,
>
> This is regarding the make check error in readable.sh
>
> https://jenkins.ceph.com/job/ceph-pull-requests/21319/
>
> We have added additional fields to the ECSubRead message type and
> updated the encode, decode of ECSubRead message to incorporate the
> newly added fields. The failure seems to happen when the object (older
> ECSubRead) is being decoded with the new decode function as it is
> expecting a larger buffer length.
>
> How do we update the test objects in ceph-object-corpus with these
> added fields ?

You don't! ceph-object-corpus exists to make sure that newer code can
read older objects. You need to update the versions used in
ENCODE_START/DECODE_START and branch internally based on the encoded
object's struct_v member. I'm not sure if there are good examples of
this in the EC utility functions yet, but if not you can check out
osd_types.[h|cc] and the encoding.h macros being invoked. :)
-Greg

Re: Coupled Layer MSR: PR 14300, ECSubRead decode fail.

[Myna V]

Thanks Greg. We will do that!

On Mon, Apr 3, 2017 at 11:37 PM, Gregory Farnum <gfarnum@redhat.com> wrote:
> On Mon, Apr 3, 2017 at 11:02 AM, Myna V <mynaramana@gmail.com> wrote:
>> Hello All,
>>
>> This is regarding the make check error in readable.sh
>>
>> https://jenkins.ceph.com/job/ceph-pull-requests/21319/
>>
>> We have added additional fields to the ECSubRead message type and
>> updated the encode, decode of ECSubRead message to incorporate the
>> newly added fields. The failure seems to happen when the object (older
>> ECSubRead) is being decoded with the new decode function as it is
>> expecting a larger buffer length.
>>
>> How do we update the test objects in ceph-object-corpus with these
>> added fields ?
>
> You don't! ceph-object-corpus exists to make sure that newer code can
> read older objects. You need to update the versions used in
> ENCODE_START/DECODE_START and branch internally based on the encoded
> object's struct_v member. I'm not sure if there are good examples of
> this in the EC utility functions yet, but if not you can check out
> osd_types.[h|cc] and the encoding.h macros being invoked. :)
> -Greg