Hi,

at CIP we need to have a clear view of what "Support" means in the context of the Super Long Term Support kernel.

++ What kind of support will CIP provide? To whom?

CIP will support its members and their developers, not system administrators or end users. With the current number of members, there should not be a need for a 'first line' of support between them and the CIP core developers, though that may change if membership grows significantly.

Commercial Linux based distributions like RHEL promise that a subset of the kernel module API and ABI remains stable within a major release, so that many out-of-tree modules can be used without needing to update the module source or binaries along with the kernel. Some IHVs rely on this to distribute driver modules in binary form.

CIP should avoid making any such promise because:

* Upstream fixes frequently change the kernel module API and/or ABI and backporting them in a way that does not is difficult and risky - CIP users set their own kernel configurations, so there will not be a single kernel ABI for IHVs to target anyway

* CIP users are responsible for binary releases of both the kernel and out-of-tree modules, so can ensure that they are properly synchronised.

* The criteria for backporting bug fixes will presumably be based on 'stable-kernel-rules.txt'. However, In CIP context, it is recommended to be more precise than that.

Best Regards

--
Agustin Benito Bethencourt
Principal Consultant - FOSS at Codethink
agustin.benito@...

Hi,

On 22/09/16 14:59, Agustin Benito Bethencourt wrote:

Hi,

at CIP we need to have a clear view of what "Support" means in the
context of the Super Long Term Support kernel.

++ What kind of support will CIP provide? To whom?

CIP will support its members and their developers, not system
administrators or end users. With the current number of members, there
should not be a need for a 'first line' of support between them and the
CIP core developers, though that may change if membership grows
significantly.

Commercial Linux based distributions like RHEL promise that a subset of
the kernel module API and ABI remains stable within a major release, so
that many out-of-tree modules can be used without needing to update the
module source or binaries along with the kernel. Some IHVs rely on this
to distribute driver modules in binary form.

CIP should avoid making any such promise because:

* Upstream fixes frequently change the kernel module API and/or ABI and
backporting them in a way that does not is difficult and risky - CIP
users set their own kernel configurations, so there will not be a single
kernel ABI for IHVs to target anyway

Correction:

Upstream fixes frequently change the kernel module API and/or ABI and backporting them in a way that is difficult and risky - CIP users set their own kernel configurations, so there will not be a single kernel ABI for IHVs to target anyway

* CIP users are responsible for binary releases of both the kernel and
out-of-tree modules, so can ensure that they are properly synchronised.

* The criteria for backporting bug fixes will presumably be based on
'stable-kernel-rules.txt'. However, In CIP context, it is recommended
to be more precise than that.

Best Regards

Best regards
--
Agustin Benito Bethencourt
Principal Consultant - FOSS at Codethink
agustin.benito@...

Hi Agustin,
Let me understand what you wrote.

CIP should avoid making any such promise because:

* Upstream fixes frequently change the kernel module API and/or ABI and
backporting them in a way that does not is difficult and risky - CIP
users set their own kernel configurations, so there will not be a
single kernel ABI for IHVs to target anyway

Correction:

Upstream fixes frequently change the kernel module API and/or ABI and
backporting them in a way that is difficult and risky - CIP users set
their own kernel configurations, so there will not be a single kernel ABI for IHVs to
target anyway

Is the correction correct?
I thought you wrote;
* Upstream fixes frequently change the kernel module API and/or ABI and
backporting them in a way that does not (change the kernel module API and/or ABI )is difficult and risky - CIP
Am I wrong?

Takuo Koguchi

Hi Koguchi-san,

I think you are right. It's my fault, sorry.

Daniel

On Fri, 2016-10-07 at 07:34 +0000, 小口琢夫 / KOGUCHI，TAKUO wrote:

Hi Agustin,
Let me understand what you wrote.

CIP should avoid making any such promise because:

* Upstream fixes frequently change the kernel module API and/or ABI and
backporting them in a way that does not is difficult and risky - CIP
users set their own kernel configurations, so there will not be a
single kernel ABI for IHVs to target anyway

Correction:

Upstream fixes frequently change the kernel module API and/or ABI and
backporting them in a way that is difficult and risky - CIP users set
their own kernel configurations, so there will not be a single kernel ABI for IHVs to
target anyway

Is the correction correct?

The first version is what I wrote, and the correction says something I
did not mean to say.

I thought you wrote;
* Upstream fixes frequently change the kernel module API and/or ABI and
backporting them in a way that does not (change the kernel module API and/or ABI )is difficult and risky - CIP
Am I wrong?

No, you understand me rightly.

Ben.

--
Ben Hutchings
Software Developer, Codethink Ltd.

On 2016-09-22 14:59, Agustin Benito Bethencourt wrote:

Hi,

at CIP we need to have a clear view of what "Support" means in the
context of the Super Long Term Support kernel.

++ What kind of support will CIP provide? To whom?

CIP will support its members and their developers, not system
administrators or end users. With the current number of members, there
should not be a need for a 'first line' of support between them and the
CIP core developers, though that may change if membership grows
significantly.

Commercial Linux based distributions like RHEL promise that a subset of
the kernel module API and ABI remains stable within a major release, so
that many out-of-tree modules can be used without needing to update the
module source or binaries along with the kernel. Some IHVs rely on this
to distribute driver modules in binary form.

CIP should avoid making any such promise because:

* Upstream fixes frequently change the kernel module API and/or ABI and
backporting them in a way that does not is difficult and risky - CIP
users set their own kernel configurations, so there will not be a single
kernel ABI for IHVs to target anyway

* CIP users are responsible for binary releases of both the kernel and
out-of-tree modules, so can ensure that they are properly synchronised.

* The criteria for backporting bug fixes will presumably be based on
'stable-kernel-rules.txt'. However, In CIP context, it is recommended
to be more precise than that.

Nit: it's stable_kernel_rules.txt. We should start this way and
augment/adjust rules after discussions as we find potential conflicts.

Sounds reasonable to me in general.

Jan

--
Siemens AG
Corporate Technology
Research & Technology Center
CT RDA ITP SES-DE
Corporate Competence Center Embedded Linux
Otto-Hahn-Ring 6
81739 Muenchen
Tel.: +49 89 636-634006
Fax: +49 89 636-33045
mailto:jan.kiszka@...

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Cromme; Managing Board: Joe Kaeser, Chairman, President and Chief
Executive Officer; Roland Busch, Lisa Davis, Klaus Helmrich, Janina
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and Munich, Germany; Commercial registries: Berlin Charlottenburg, HRB
12300, Munich, HRB 6684; WEEE-Reg.-No. DE 23691322

Hi,

(2016/09/27 17:29), Agustin Benito Bethencourt wrote:

Hi,

On 22/09/16 14:59, Agustin Benito Bethencourt wrote:

Hi,

at CIP we need to have a clear view of what "Support" means in the
context of the Super Long Term Support kernel.

++ What kind of support will CIP provide? To whom?

CIP will support its members and their developers, not system
administrators or end users. With the current number of members, there
should not be a need for a 'first line' of support between them and the
CIP core developers, though that may change if membership grows
significantly.

We (our company members) agree.

Commercial Linux based distributions like RHEL promise that a subset of
the kernel module API and ABI remains stable within a major release, so
that many out-of-tree modules can be used without needing to update the
module source or binaries along with the kernel. Some IHVs rely on this
to distribute driver modules in binary form.

CIP should avoid making any such promise because:

* Upstream fixes frequently change the kernel module API and/or ABI and
backporting them in a way that does not is difficult and risky - CIP
users set their own kernel configurations, so there will not be a single
kernel ABI for IHVs to target anyway

Correction:

Upstream fixes frequently change the kernel module API and/or ABI and
backporting them in a way that is difficult and risky - CIP users set
their own kernel configurations, so there will not be a single kernel
ABI for IHVs to target anyway

* CIP users are responsible for binary releases of both the kernel and
out-of-tree modules, so can ensure that they are properly synchronised.

* The criteria for backporting bug fixes will presumably be based on
'stable-kernel-rules.txt'. However, In CIP context, it is recommended
to be more precise than that.

We think CIP doesn't need to kepp the kernel API/ABI.

Best regards,

Hidehiro Kawai
Hitachi, Ltd. Research & Development Group