[ovs-discuss] Error - build kernel module (openvswitch-2.0.0.tar.gz) on RHEL 7 Beta

[Jesse Gross]

On Tue, May 13, 2014 at 1:52 PM, Andrey Korolyov <andrey at xdel.ru> wrote:
> On Wed, May 14, 2014 at 12:44 AM, Jesse Gross <jesse at nicira.com> wrote:
>> On Tue, May 13, 2014 at 1:25 PM, Andrey Korolyov <andrey at xdel.ru> wrote:
>>> On Wed, May 14, 2014 at 12:19 AM, Jesse Gross <jesse at nicira.com> wrote:
>>>> On Tue, May 13, 2014 at 1:58 AM, Andrey Korolyov <andrey at xdel.ru> wrote:
>>>>> On Tue, May 13, 2014 at 4:41 AM, Jesse Gross <jesse at nicira.com> wrote:
>>>>>> On Mon, May 12, 2014 at 2:04 PM, Andrey Korolyov <andrey at xdel.ru> wrote:
>>>>>>> On Tue, May 13, 2014 at 12:58 AM, Jesse Gross <jesse at nicira.com> wrote:
>>>>>>>> On Sat, May 10, 2014 at 2:13 PM, Andrey Korolyov <andrey at xdel.ru> wrote:
>>>>>>>>> Hello,
>>>>>>>>>
>>>>>>>>> sorry for bringing this old thread on top, but right now building
>>>>>>>>> against current RHEL 3.10.121.el7 seems not possible without
>>>>>>>>> patchwork. After fixing some obvious kversion checks and code
>>>>>>>>> snippets, I had stuck on f067987973facf28916a2f5ee48bf02ce5938bf8:
>>>>>>>>>
>>>>>>>>> In file included from
>>>>>>>>> /builder/rpmbuild/BUILD/openvswitch-2.1.3/_default/../datapath/linux/compat/include/net/gre.h:9:0,
>>>>>>>>>                  from
>>>>>>>>> /builder/rpmbuild/BUILD/openvswitch-2.1.3/_default/datapath/linux/vport-gre.c:44:
>>>>>>>>> include/net/gre.h: In function ‘gre_handle_offloads’:
>>>>>>>>> include/net/gre.h:42:2: error: implicit declaration of function
>>>>>>>>> ‘iptunnel_handle_offloads’ [-Werror=implicit-function-declaration]
>>>>>>>>>   return iptunnel_handle_offloads(skb, gre_csum, SKB_GSO_GRE);
>>>>>>>>>   ^
>>>>>>>>> include/net/gre.h:42:2: warning: return makes pointer from integer
>>>>>>>>> without a cast [enabled by default]
>>>>>>>>> cc1: some warnings being treated as errors
>>>>>>>>>
>>>>>>>>> Bare look says that this snippet should be modified more intensively
>>>>>>>>> than by one-line patch to work well, so I thought it would be better
>>>>>>>>> to ask there on how to fix this properly.
>>>>>>>>
>>>>>>>> What version of OVS is this and which patch are you specifically referring to?
>>>>>>>
>>>>>>> Sorry if it was unclear, I pointed hash above, it` s 2.1.2. By patch I
>>>>>>> meant one-liners which helps to mock kernel version checking in the
>>>>>>> places where conflict of backported functions can take place. I
>>>>>>> replaced failed checks one by one and then stuck with error above.
>>>>>>> Actually, both gre.h - from compat/ and from RH kernel headers
>>>>>>> resulting to this error if one want to try to point them explicitly.
>>>>>>
>>>>>> Can you post the changes you had to make to get to this point? I would
>>>>>> expect that HAVE_GRE_CISCO_REGISTER would be defined and so there
>>>>>> should be relatively little that is version specific.
>>>>>>
>>>>>> Have you also tried branch-2.2 or master?
>>>>>
>>>>> There are no such thing in public repo as branch-2.2, so with master
>>>>> 75264fe5f1ceb73a33bcc8e1adb3ad9aad57237d I`ve got the same. Please
>>>>> take a look on the attached patch. Also mind that the change in
>>>>> datapath.c is purely a mock to pass through it to next failure and
>>>>> shouldn`t go anywhere :)
>>>>
>>>> OK - I see. These changes are just miscellaneous backports and not in
>>>> the tunnel code as I thought you were saying. I don't have a copy of
>>>> the RHEL 7 beta source handy but it seems like this could be a missing
>>>> definition in those headers. OVS should just be using the tunnel code
>>>> from the kernel headers and the use of iptunnel_handle_offloads()
>>>> would be from there. If they use it, they should also define it...
>>>
>>> You can use srpm for headers:
>>> http://ftp.redhat.com/redhat/rhel/rc/7/ComputeNode/source/tree/Packages/kernel-3.10.0-121.el7.src.rpm
>>
>> Since you're already working in this code, it might be faster for you
>> to take a look.
>
> Ok, will check tomorrow morning, but since RH-Oracle counterstand took
> place, there are no reliable changelog except text remarks in the spec
> file, so it`s a bit uneasy to say which bits should be presented and
> which should not...

I would just look into how and where iptunnel_handle_offloads is used
and defined. I don't think that there is really more to it than that.
OVS is using the GRE receive code wholesale in this version so there
shouldn't be any tricky dependencies.