On Mon, Mar 22, 2021 at 10:49:54AM +0100, Christian Ehrhardt wrote:

On Thu, Mar 18, 2021 at 7:25 PM Pai G, Sunil [off-list ref] wrote:

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Hi Christian, Ilya

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-----Original Message-----
From: Ilya Maximets <i.maximets@ovn.org>
Sent: Thursday, March 18, 2021 8:18 PM
To: Pai G, Sunil <redacted>; Christian Ehrhardt
[off-list ref]; Stokes, Ian [off-list ref];
Ilya Maximets [off-list ref]; Govindharajan, Hariprasad
[off-list ref]
Cc: Richardson, Bruce <redacted>; Luca Boccassi
[off-list ref]; stable@dpdk.org; dev [off-list ref]; James Page
[off-list ref]
Subject: Re: [dpdk-dev] 19.11.4 patches review and test

On 3/18/21 2:36 PM, Pai G, Sunil wrote:

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Hey Christian,

<snipped>

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back  in 19.11.4 these DPDK changes were not picked up as they have
broken builds as discussed here.
Later on the communication was that all this works fine now and
thereby Luca has "reverted the reverts" in 19.11.6 [1].

But today we were made aware that still no OVS 2.13 builds against a
DPDK that has those changes.
Not 2.13.1 as we have it in Ubuntu nor (if it needs some OVS changes
backported) the recent 2.13.3 does build.
They still fail with the very same issue I reported [2] back then.

Unfortunately I have just released 19.11.7 so I can't revert them
there - but OTOH reverting and counter reverting every other release
seems wrong anyway.

It is wrong indeed, but the main question here is why these patches was
backported to stable release in a first place?

Looking at these patches, they are not actual bug fixes but more like "nice to
have" features that additionally breaks the way application links with DPDK.
Stuff like that should not be acceptable to the stable release without a strong
justification or, at least, testing with actual applications.

I agree, but TBH IIRC these changes were initially by OVS people :-)
One could chase down the old talks between Luca and the requesters, but I don't
think that gains us that much.

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Since we already have a revert of revert, revert of revert of revert doesn't
seem so bad.

As long as we don't extend this series, yeah

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I wanted to ask if there is a set of patches that OVS would need to
backport to 2.13.x to make this work?
If they could be identified and prepared Distros could use them on
2.13.3 asap and 2.13.4 could officially release them for OVS later on.

But for that we'd need a hint which OVS changes that would need to be.
All I know atm is from the testing reports on DPDK it seems that OVS
2.14.3 and 2.15 are happy with the new DPDK code.

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Do you have pointers on what 2.13.3 would need to get backported to
work again in regard to this build issue.

You would need to use partial contents from patch :
http://patchwork.ozlabs.org/project/openvswitch/patch/1608142365-

26215

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-1-git-send-email-ian.stokes@intel.com/

If you'd like me to send patches which would work with 2.13, 2.14, I'm
ok with that too.[keeping only those parts from patch which fixes the issue

you see.] But we must ensure it doesn’t cause problems for OVS too.

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Your thoughts Ilya ?

We had more fixes on top of this particular patch and I'd like to not cherry-
pick and re-check all of this again.

I agree, we had more fixes on top of this. It would be risky to cherry-pick.
So it might be a better option to revert.

I agree, as far as I assessed the situation it would mean the revert
of the following list.
And since that is a lot of "reverts" in the string, to be clear it means that
those original changes would not be present anymore in 19.11.x.

f49248a990 Revert "Revert "build/pkg-config: prevent overlinking""
39586a4cf0 Revert "Revert "build/pkg-config: improve static linking flags""
906e935a1f Revert "Revert "build/pkg-config: output drivers first for
static build""
deebf95239 Revert "Revert "build/pkg-config: move pkg-config file creation""
a3bd9a34bf Revert "Revert "build: always link whole DPDK static libraries""
d4bc124438 Revert "Revert "devtools: test static linkage with pkg-config""

But to avoid going back&forth I'd prefer to have a signed-off on that
approach from:
- Luca (for 19.11.6 which has added the changes)
- Bruce (for being involved in the old&new case in general)
- Thomas (for general master maintainer thoughts)

If this is what is needed to ensure OVS can continue to use this release
series, then I am absolutely fine with it.

/Bruce