[Pkg-dpdk-devel] OVS cannot find DPDK

[Christian Ehrhardt]

On Tue, Sep 1, 2020 at 1:13 PM Christian Ehrhardt
<christian.ehrhardt at canonical.com> wrote:
>
> On Tue, Sep 1, 2020 at 12:17 PM Christian Ehrhardt
> <christian.ehrhardt at canonical.com> wrote:
> >
> > On Tue, Sep 1, 2020 at 10:46 AM Luca Boccassi <bluca at debian.org> wrote:
> > >
> > > On Mon, 2020-08-31 at 23:57 +0200, Thomas Goirand wrote:
> > > > Dear DPDK package maintainers,
> > > >
> > > > When I build OVS, I get:
> > > >
> > > > configure: error: Could not find DPDK library in default search path,
> > > > Use --with-dpdk to specify the DPDK library installed in non-standard
> > > > location
> > > >
> > > > How can I fix this and resolve the FTBFS bug on OVS?
> > > >
> > > > Cheers,
> > > >
> > > > Thomas Goirand (zigo)
> > >
> > > Hi,
> > >
> > > I assume you refer to:
> > > https://bugs.debian.org/cgi-bin/bugreport.cgi?bug=966921
> > >
> > > This is strange - the last src:dpdk upload was on 2020-06-20, and the
> > > last src:openvswitch upload was on 2020-06-30, and everything built
> > > fine, and you can see from the buildd logs that it used the current
> > > version:
> > >
> > > https://buildd.debian.org/status/fetch.php?pkg=openvswitch&arch=amd64&ver=2.13.0%2Bdfsg1-12&stamp=1593532578&raw=0
> > >
> > > The reporter says it's not building on buildds, but in a custom
> > > environment on AWS, maybe something is wrong there? Or some other
> > > build-dep changed in the meanwhile that broke the autoconf check in
> > > openvswitch?
> > >
> > > http://qa-logs.debian.net/2020/08/02/openvswitch_2.13.0+dfsg1-12_unstable.log
> > >
> > > Christian, any idea? Maybe the PKG_CHECK_MODULES_STATIC goes wrong for
> > > some reason, so it falls back to try the old, deprecated -ldpdk?
> >
> >
> > I checked the last Ubuntu builds but it worked for us just fine as
> > well (a bit earlier than yours).
> >
> > I've still had the latest DPDK in a PPA at [1] so I have thrown a
> > build of the recent 2.13.1 against it.
> > That build worked for the configure part that is in question here (it
> > seems to have linking issues later on thou).
>
> Ha I have at least a theory :-)
> I was checking for that later FTBFS that I've found (later in linking)
> to do so I have built it in different environments.
>
> On the Ubuntu side I have Focal / Groovy which mostly differ in the
> toolchain used.
> Dpdk is on an almost identical 19.11.3 on both.
> And we have OVS 2.13 as well as a prepared upload for 2.13.1 that I can use
>
> What I've seen is:
> (1) new-toolchain + dpdk 19.11.3 + ovs 2.13.1 => "configure: error:
> Could not find DPDK library"
> (2) new-toolchain + dpdk 19.11.4 + ovs 2.13.1 => "undefined reference
> to `rte_vdev_register'"
> (3) old-toolchain + dpdk 19.11.3 + ovs 2.13.1 => "works"
> (4) old-toolchain + dpdk 19.11.3 + ovs 2.13.0 => "works"
>
> (3)+(4) are as the working builds of the past
> We can almost safely assume it is a toolchain change that broke it.
> (1) vs (2) indicates that 19.11.4 tried to fix something and did it
> for the configure, but not for the full compile.


(2) comes down to breakage in DPDK 19.11.4 linking.
I've reported that at:
http://mails.dpdk.org/archives/stable/2020-September/024796.html
and Luca will take care of that.

Back to the OVS config problem, I've reproduced and found that it is
indeed toolchain related (affects old and new versions of OVS).
It seems it is indeed a problem in libdpdk-dev

$ cat /usr/lib/x86_64-linux-gnu/pkgconfig/libdpdk.pc
[...]
Libs: -L${libdir} [...] -lnuma -lpcap -lIPSec_MB
/usr/lib/gcc/x86_64-linux-gnu/9/../../../x86_64-linux-gnu/libfdt.so

The above path shouldn't be there as-is.
It should not be versioned to ...-gnu/9/../ which is what fails now
that we are on gcc-10.

I need to look if I can find where exactly this comes from ...

> PPAs to digest through build logs:
> https://launchpad.net/~ci-train-ppa-service/+archive/ubuntu/4240/+packages
> https://launchpad.net/~ci-train-ppa-service/+archive/ubuntu/4239/+packages
> https://launchpad.net/~ci-train-ppa-service/+archive/ubuntu/4222/+packages
>
> > Of bug 966921 is there any chance to get the config.log of it?
> > Since it seems non reproducible elsewhere that would be the next place to check.
> >
> > @Thomas you say it fails on your laptop, does the config.log show
> > anything more useful about how it broke?
> >
> > [1]: https://launchpad.net/~ci-train-ppa-service/+archive/ubuntu/4222/+packages
> >
> >
> >
> > > https://sources.debian.org/src/openvswitch/2.13.0+dfsg1-12/acinclude.m4/#L322
> > >
> > > --
> > > Kind regards,
> > > Luca Boccassi
> >
> >
> >
> > --
> > Christian Ehrhardt
> > Staff Engineer, Ubuntu Server
> > Canonical Ltd
>
>
>
> --
> Christian Ehrhardt
> Staff Engineer, Ubuntu Server
> Canonical Ltd



-- 
Christian Ehrhardt
Staff Engineer, Ubuntu Server
Canonical Ltd