devstack/lib/ovs fails on fedora

[Lucas Alvares Gomes]

The devstack/lib/ovs module doesn't currently work on a Fedora 28 base host OS. Here's the failures I've bumped into when I've attempted to stack my DevStack cloud on a Fedora 28 host OS.

Problem 1:

NOTE: if kernel-devel-4.17.19_200.fc28.x86_64 or kernel-headers-4.17.19_200.fc28.x86_64 installation
failed, please, provide a repository with the package, or yum update / reboot
your machine to get the latest kernel.
Last metadata expiration check: 0:25:41 ago on Fri 31 Aug 2018 09:13:54 AM UTC.
No match for argument: kernel-devel-4.17.19_200.fc28.x86_64
Error: Unable to find a match
YUM_FAILED 1
Last metadata expiration check: 0:25:43 ago on Fri 31 Aug 2018 09:13:54 AM UTC.
No match for argument: kernel-devel-4.17.19_200.fc28.x86_64
Error: Unable to find a match
YUM_FAILED 1
Error on exit
World dumping... see /opt/stack/logs/worlddump-2018-08-31-093938.txt for details

Apparently the kernel-devel and kernel-headers packages have different patch versions (all packages have been updated prior to starting devstack). See:

 kernel-devel: 4.17.19-200.fc28
 kernel-headers: 4.17.19-1.fc28

We need to account for that.

Problem 2:

ln -s /opt/stack/ovs/datapath/linux/../linux/compat/utils.c
ln -s /opt/stack/ovs/datapath/linux/../vport-geneve.c
ln -s /opt/stack/ovs/datapath/linux/../vport-gre.c
ln -s /opt/stack/ovs/datapath/linux/../vport-lisp.c
ln -s /opt/stack/ovs/datapath/linux/../vport-stt.c
ln -s /opt/stack/ovs/datapath/linux/../vport-vxlan.c
make -C /lib/modules/4.17.19-200.fc28.x86_64/build M=/opt/stack/ovs/datapath/linux modules
make[4]: Entering directory '/usr/src/kernels/4.17.19-200.fc28.x86_64'
Makefile:974: *** "Cannot generate ORC metadata for CONFIG_UNWINDER_ORC=y, please install libelf-dev, libelf-devel or elfutils-libelf-devel". Stop.
make[4]: Leaving directory '/usr/src/kernels/4.17.19-200.fc28.x86_64'
make[3]: *** [Makefile.main:71: default] Error 2
make[3]: Leaving directory '/opt/stack/ovs/datapath/linux'
make[2]: *** [Makefile:572: all-recursive] Error 1
make[2]: Leaving directory '/opt/stack/ovs/datapath'
make[1]: *** [Makefile:5795: all-recursive] Error 1
make[1]: Leaving directory '/opt/stack/ovs'
make: *** [Makefile:3411: all] Error 2
Error on exit
World dumping... see /opt/stack/logs/worlddump-2018-08-31-104046.txt for details

When compiling OVS. To fix this we just need to install the elfutils-libelf-devel package.

[OpenStack Infra (hudson-openstack)]

Fix proposed to branch: master
Review: https://review.openstack.org/598960

[OpenStack Infra (hudson-openstack)]

Reviewed: https://review.openstack.org/598960
Committed: https://git.openstack.org/cgit/openstack/neutron/commit/?id=987e8b0cc4cc6a39ac0d4d32a47764f833c57a2e
Submitter: Zuul
Branch: master

commit 987e8b0cc4cc6a39ac0d4d32a47764f833c57a2e
Author: Lucas Alvares Gomes <email address hidden>
Date: Fri Aug 31 14:44:31 2018 +0100

    Fix devstack/lib/ovs to run with Fedora 28

    The patch is fixing two problems found when stacking DevStack on a
    Fedora 28 host OS.

    Problem 1: Account to the different patch versions between the
    kernel-devel and kernel-headers packages.

    Problem 2: Install the elfutils-libelf-devel package which is needed to
    compile OVS.

    For more a detailed information about each problem, check the bug linked
    in this patch.

    Closes-Bug: #1790143
    Change-Id: Idfdee28124ff19272abcaaa3adade0435e3e474a

[OpenStack Infra (hudson-openstack)]

This issue was fixed in the openstack/neutron 14.0.0.0b1 development milestone.